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Q: How can I make a UITextField move up when the keyboard is present - on starting to edit? With the iOS SDK:
I have a UIView with UITextFields that bring up a keyboard. I need it to be able to:

*

*Allow scrolling of the contents of the UIScrollView to see the other text fields once the keyboard is brought up

*Automatically "jump" (by scrolling up) or shortening
I know that I need a UIScrollView.  I've tried changing the class of my UIView to a UIScrollView, but I'm still unable to scroll the textboxes up or down.
Do I need both a UIView and a UIScrollView? Does one go inside the other?
What needs to be implemented in order to automatically scroll to the active text field?
Ideally as much of the setup of the components as possible will be done in Interface Builder. I'd like to only write code for what needs it.
Note: the UIView (or UIScrollView) that I'm working with is brought up by a tabbar (UITabBar), which needs to function as normal.

I am adding the scroll bar just for when the keyboard comes up.  Even though it's not needed, I feel like it provides a better interface because then the user can scroll and change textboxes, for example.
I've got it working where I change the frame size of the UIScrollView when the keyboard goes up and down. I'm simply using:
-(void)textFieldDidBeginEditing:(UITextField *)textField {
    //Keyboard becomes visible
    scrollView.frame = CGRectMake(scrollView.frame.origin.x,
                                  scrollView.frame.origin.y,
    scrollView.frame.size.width,
    scrollView.frame.size.height - 215 + 50);   // Resize
}

-(void)textFieldDidEndEditing:(UITextField *)textField {
    // Keyboard will hide
    scrollView.frame = CGRectMake(scrollView.frame.origin.x,
                                  scrollView.frame.origin.y,
                                  scrollView.frame.size.width,
                                  scrollView.frame.size.height + 215 - 50); // Resize
}

However, this doesn't automatically "move up" or center the lower text fields in the visible area, which is what I would really like.

A:
For Swift Programmers :

This will do everything for you, just put these in your view controller class and implement the UITextFieldDelegate to your view controller & set the textField's delegate to self
textField.delegate = self // Setting delegate of your UITextField to self

Implement the delegate callback methods:
func textFieldDidBeginEditing(textField: UITextField) {
    animateViewMoving(true, moveValue: 100)
}

func textFieldDidEndEditing(textField: UITextField) {
    animateViewMoving(false, moveValue: 100)
}

// Lifting the view up
func animateViewMoving (up:Bool, moveValue :CGFloat){
    let movementDuration:NSTimeInterval = 0.3
    let movement:CGFloat = ( up ? -moveValue : moveValue)
    UIView.beginAnimations( "animateView", context: nil)
    UIView.setAnimationBeginsFromCurrentState(true)
    UIView.setAnimationDuration(movementDuration )
    self.view.frame = CGRectOffset(self.view.frame, 0,  movement)
    UIView.commitAnimations()
}

For Swift 4, 4.2, 5:
Change
self.view.frame = CGRectOffset(self.view.frame, 0,  movement)

to
self.view.frame = self.view.frame.offsetBy(dx: 0, dy: movement)

Last note about this implementation: If you push another view controller onto the stack while the keyboard is shown, this will create an error where the view is returned back to its center frame but keyboard offset is not reset. For example, your keyboard is the first responder for nameField, but then you push a button that pushes your Help View Controller onto your stack. To fix the offset error, make sure to call nameField.resignFirstResponder() before leaving the view controller, ensuring that the textFieldDidEndEditing delegate method is called as well. I do this in the viewWillDisappear method.

A: Note: this answer assumes your textField is in a scrollView.
I prefer to deal with this using scrollContentInset and scrollContentOffset instead of messing with the frames of my view.
First let's listen for the keyboard notifications
//call this from viewWillAppear
-(void)addKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification
                                               object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillHide:)
                                                 name:UIKeyboardWillHideNotification
                                               object:nil];
}
//call this from viewWillDisappear
-(void)removeKeyboardNotifications{
    [[NSNotificationCenter default
    Center] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

Next step is to keep a property that represents the current first responder (UITextfield/ UITextVIew that currently has the keyboard).
We use the delegate methods to set this property. If you're using another component, you will need something similar.
Note that for textfield we set it in didBeginEditing and for textView in shouldBeginEditing. This is because textViewDidBeginEditing gets called after UIKeyboardWillShowNotification for some reason.
-(BOOL)textViewShouldBeginEditing:(UITextView * )textView{
    self.currentFirstResponder = textView;
    return YES;
}

-(void)textFieldDidBeginEditing:(UITextField *)textField{
    self.currentFirstResponder = textField;
}

Finally, here's  the magic
- (void)keyboardWillShow:(NSNotification*)aNotification{
    NSDictionary* info = [aNotification userInfo];
    CGRect kbFrame = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];

    /*if currentFirstResponder is overlayed by the keyboard, move it so it bottom ends where the keyboard begins*/
    if(self.currentFirstResponder){

        //keyboard origin in currentFirstResponderFrame
        CGPoint keyboardOrigin = [self.currentFirstResponder convertPoint:kbFrame.origin fromView:nil];

        float spaceBetweenFirstResponderAndKeyboard = abs(self.currentFirstResponder.frame.size.height-keyboardOrigin.y);

        //only scroll the scrollview if keyboard overlays the first responder
        if(spaceBetweenFirstResponderAndKeyboard>0){
            //if i call setContentOffset:animate:YES it behaves differently, not sure why
            [UIView animateWithDuration:0.25 animations:^{
                [self.scrollView setContentOffset:CGPointMake(0,self.scrollView.contentOffset.y+spaceBetweenFirstResponderAndKeyboard)];
            }];
        }
    }

    //set bottom inset to the keyboard height so you can still scroll the whole content

    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbFrame.size.height, 0.0);
    _scrollView.contentInset = contentInsets;
    _scrollView.scrollIndicatorInsets = contentInsets;

}

- (void)keyboardWillHide:(NSNotification*)aNotification{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    _scrollView.contentInset = contentInsets;
    _scrollView.scrollIndicatorInsets = contentInsets;
}

A: This is the solution using Swift.
import UIKit

class ExampleViewController: UIViewController, UITextFieldDelegate {

    @IBOutlet var scrollView: UIScrollView!

    @IBOutlet var textField1: UITextField!
    @IBOutlet var textField2: UITextField!
    @IBOutlet var textField3: UITextField!
    @IBOutlet var textField4: UITextField!
    @IBOutlet var textField5: UITextField!

    var activeTextField: UITextField!

    // MARK: - View
    override func viewDidLoad() {
        super.viewDidLoad()
        self.textField1.delegate = self
        self.textField2.delegate = self
        self.textField3.delegate = self
        self.textField4.delegate = self
        self.textField5.delegate = self
    }

    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)
        self.registerForKeyboardNotifications()
    }

    override func viewWillDisappear(animated: Bool) {
        super.viewWillDisappear(animated)
        self.unregisterFromKeyboardNotifications()
    }

    // MARK: - Keyboard

    // Call this method somewhere in your view controller setup code.
    func registerForKeyboardNotifications() {
        let center:  NSNotificationCenter = NSNotificationCenter.defaultCenter()
        center.addObserver(self, selector: "keyboardWasShown:", name: UIKeyboardDidShowNotification, object: nil)
        center.addObserver(self, selector: "keyboardWillBeHidden:", name: UIKeyboardWillHideNotification, object: nil)
    }

    func unregisterFromKeyboardNotifications () {
        let center:  NSNotificationCenter = NSNotificationCenter.defaultCenter()
        center.removeObserver(self, name: UIKeyboardDidShowNotification, object: nil)
        center.removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
    }

    // Called when the UIKeyboardDidShowNotification is sent.
    func keyboardWasShown (notification: NSNotification) {
        let info : NSDictionary = notification.userInfo!
        let kbSize = (info.objectForKey(UIKeyboardFrameBeginUserInfoKey)?.CGRectValue() as CGRect!).size

        let contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
        scrollView.contentInset = contentInsets;
        scrollView.scrollIndicatorInsets = contentInsets;

        // If active text field is hidden by keyboard, scroll it so it's visible
        // Your app might not need or want this behavior.
        var aRect = self.view.frame
        aRect.size.height -= kbSize.height;
        if (!CGRectContainsPoint(aRect, self.activeTextField.frame.origin) ) {
            self.scrollView.scrollRectToVisible(self.activeTextField.frame, animated: true)
        }
    }

    // Called when the UIKeyboardWillHideNotification is sent
    func keyboardWillBeHidden (notification: NSNotification) {
        let contentInsets = UIEdgeInsetsZero;
        scrollView.contentInset = contentInsets;
        scrollView.scrollIndicatorInsets = contentInsets;
    }

    // MARK: -  Text Field

    func textFieldDidBeginEditing(textField: UITextField) {
        self.activeTextField = textField
    }

    func textFieldDidEndEditing(textField: UITextField) {
        self.activeTextField = nil
    }

}

A: You need to add scrollview programmatically with specific frame size. You have to add UIScrollViewDelegate in .h file. You have to enable scrollview for that you need to write following in viewDidLoad().
scrollview.scrollEnabled=YES;
scrollview.delegate=self;

scrollview.frame = CGRectMake(x,y,width,height);
//---set the content size of the scroll view---

[scrollview setContentSize:CGSizeMake(height,width)];

This way, you can add your x, y, width and height values.

A: Try this:
-(void)textFieldDidBeginEditing:(UITextField *)sender
{
    if ([sender isEqual:self.m_Sp_Contact])
    {
        [self.m_Scroller setContentOffset:CGPointMake(0, 105)animated:YES];
    }
}

A: Swift 2.0:
Add a UIScrollView and add textFields on the top of it. Make storyboard references to VC.
@IBOutlet weak var username: UITextField!
@IBOutlet weak var password: UITextField!
@IBOutlet weak var scrollView: UIScrollView!

Add these methods : UITextFieldDelegate  & UIScrollViewDelegate.
//MARK:- TEXTFIELD METHODS
    func textFieldShouldReturn(textField: UITextField) -> Bool {

        if(username.returnKeyType == UIReturnKeyType.Default) {
            password.becomeFirstResponder()
        }
        textField.resignFirstResponder()
        return true
    }
    func textFieldDidBeginEditing(textField: UITextField) {

        dispatch_async(dispatch_get_main_queue()) {

            let scrollPoint:CGPoint = CGPointMake(0,textField.frame.origin.y/4)
            self.scrollView!.setContentOffset(scrollPoint, animated: true);
        }
    }
    func textFieldShouldEndEditing(textField: UITextField) -> Bool {

        dispatch_async(dispatch_get_main_queue()) {
          UIView.animateWithDuration(0, animations: { self.scrollView!.setContentOffset(CGPointZero,animated: true) })
        }
        return true
    }
    override func touchesBegan(touches: Set<UITouch>,
        withEvent event: UIEvent?) {
            self.view.endEditing(true)
    }
    func scrollViewWillBeginDragging(scrollView: UIScrollView) {
        self.scrollView.scrollEnabled =  true

        dispatch_async(dispatch_get_main_queue()) {
            UIView.animateWithDuration(0, animations: { self.scrollView!.setContentOffset(CGPointZero,animated: true)

            })
        }
    }

A: There are already a lot of answers, but still none of the solutions above had all the fancy positioning stuff required for a "perfect" bug-free, backwards compatible and flicker-free animation. (bug when animating frame/bounds and contentOffset together, different interface orientations, iPad split keyboard, ...)
Let me share my solution:
(assuming you have set up UIKeyboardWill(Show|Hide)Notification)
// Called when UIKeyboardWillShowNotification is sent
- (void)keyboardWillShow:(NSNotification*)notification
{
    // if we have no view or are not visible in any window, we don't care
    if (!self.isViewLoaded || !self.view.window) {
        return;
    }

    NSDictionary *userInfo = [notification userInfo];

    CGRect keyboardFrameInWindow;
    [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] getValue:&keyboardFrameInWindow];

    // the keyboard frame is specified in window-level coordinates. this calculates the frame as if it were a subview of our view, making it a sibling of the scroll view
    CGRect keyboardFrameInView = [self.view convertRect:keyboardFrameInWindow fromView:nil];

    CGRect scrollViewKeyboardIntersection = CGRectIntersection(_scrollView.frame, keyboardFrameInView);
    UIEdgeInsets newContentInsets = UIEdgeInsetsMake(0, 0, scrollViewKeyboardIntersection.size.height, 0);

    // this is an old animation method, but the only one that retains compaitiblity between parameters (duration, curve) and the values contained in the userInfo-Dictionary.
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:[[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
    [UIView setAnimationCurve:[[userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue]];

    _scrollView.contentInset = newContentInsets;
    _scrollView.scrollIndicatorInsets = newContentInsets;

    /*
     * Depending on visual layout, _focusedControl should either be the input field (UITextField,..) or another element
     * that should be visible, e.g. a purchase button below an amount text field
     * it makes sense to set _focusedControl in delegates like -textFieldShouldBeginEditing: if you have multiple input fields
     */
    if (_focusedControl) {
        CGRect controlFrameInScrollView = [_scrollView convertRect:_focusedControl.bounds fromView:_focusedControl]; // if the control is a deep in the hierarchy below the scroll view, this will calculate the frame as if it were a direct subview
        controlFrameInScrollView = CGRectInset(controlFrameInScrollView, 0, -10); // replace 10 with any nice visual offset between control and keyboard or control and top of the scroll view.

        CGFloat controlVisualOffsetToTopOfScrollview = controlFrameInScrollView.origin.y - _scrollView.contentOffset.y;
        CGFloat controlVisualBottom = controlVisualOffsetToTopOfScrollview + controlFrameInScrollView.size.height;

        // this is the visible part of the scroll view that is not hidden by the keyboard
        CGFloat scrollViewVisibleHeight = _scrollView.frame.size.height - scrollViewKeyboardIntersection.size.height;

        if (controlVisualBottom > scrollViewVisibleHeight) { // check if the keyboard will hide the control in question
            // scroll up until the control is in place
            CGPoint newContentOffset = _scrollView.contentOffset;
            newContentOffset.y += (controlVisualBottom - scrollViewVisibleHeight);

            // make sure we don't set an impossible offset caused by the "nice visual offset"
            // if a control is at the bottom of the scroll view, it will end up just above the keyboard to eliminate scrolling inconsistencies
            newContentOffset.y = MIN(newContentOffset.y, _scrollView.contentSize.height - scrollViewVisibleHeight);

            [_scrollView setContentOffset:newContentOffset animated:NO]; // animated:NO because we have created our own animation context around this code
        } else if (controlFrameInScrollView.origin.y < _scrollView.contentOffset.y) {
            // if the control is not fully visible, make it so (useful if the user taps on a partially visible input field
            CGPoint newContentOffset = _scrollView.contentOffset;
            newContentOffset.y = controlFrameInScrollView.origin.y;

            [_scrollView setContentOffset:newContentOffset animated:NO]; // animated:NO because we have created our own animation context around this code
        }
    }

    [UIView commitAnimations];
}

// Called when the UIKeyboardWillHideNotification is sent
- (void)keyboardWillHide:(NSNotification*)notification
{
    // if we have no view or are not visible in any window, we don't care
    if (!self.isViewLoaded || !self.view.window) {
        return;
    }

    NSDictionary *userInfo = notification.userInfo;

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:[[userInfo valueForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
    [UIView setAnimationCurve:[[userInfo valueForKey:UIKeyboardAnimationCurveUserInfoKey] intValue]];

    // undo all that keyboardWillShow-magic
    // the scroll view will adjust its contentOffset apropriately
    _scrollView.contentInset = UIEdgeInsetsZero;
    _scrollView.scrollIndicatorInsets = UIEdgeInsetsZero;

    [UIView commitAnimations];
}

A: Shiun said "As it turned out, I believe the UIScrollView actually implicitly brings the currently edited UITextField into the viewable window implicitly"   This seems to be true for iOS 3.1.3, but not 3.2, 4.0, or 4.1.  I had to add an explicit scrollRectToVisible in order to make the UITextField visible on iOS >= 3.2.

A: Here is a free library for keyboard handling Keyboard-Handling-in-iPhone-Applications. You need write just one line of code:
[AutoScroller addAutoScrollTo:scrollView];

This is awesome to handle keyboard in forms

A: I think that the best approach is to use protocol-oriented programming if you are using Swift.
First of all you must create a KeyboardCapable protocol, that gives to any UIViewController conforming it the ability to register and unregister keyboard observers:
import Foundation
import UIKit

protocol KeyboardCapable: KeyboardAnimatable {
    func keyboardWillShow(notification: NSNotification)
    func keyboardWillHide(notification: NSNotification)
}

extension KeyboardCapable where Self: UIViewController {
    func registerKeyboardNotifications() {
        NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name:UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name:UIKeyboardWillHideNotification, object: nil)
    }

    func unregisterKeyboardNotifications() {
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillShowNotification, object: nil)
        NSNotificationCenter.defaultCenter().removeObserver(self, name: UIKeyboardWillHideNotification, object: nil)
    }
}

You've notice the extraneous KeyboardAnimatable keyword on the above piece of code. It's just the name of the next protocol we need to create:
import Foundation
import UIKit

protocol KeyboardAnimatable {

}

extension KeyboardAnimatable where Self: UIViewController {
    func performKeyboardShowFullViewAnimation(withKeyboardHeight height: CGFloat, andDuration duration: NSTimeInterval) {
        UIView.animateWithDuration(duration, animations: { () -> Void in
            self.view.frame = CGRectMake(view.frame.origin.x, -height, view.bounds.width, view.bounds.height)
            }, completion: nil)
    }

    func performKeyboardHideFullViewAnimation(withDuration duration: NSTimeInterval) {
        UIView.animateWithDuration(duration, animations: { () -> Void in
            self.view.frame = CGRectMake(view.frame.origin.x, 0.0, view.bounds.width, view.bounds.height)
            }, completion: nil)
    }
}

This KeyboardAnimatable protocol, gives all UIViewController conforming it two methods that will animate the whole view up and down, respectively.
Okay so if KeyboardCapable conforms to KeyboardAnimatable, all UIViewController conforming to KeyboardCapable, also conforms to KeyboardAnimatable. That's cool.
Let's see a UIViewController conforming KeyboardCapable, and reacting to keyboard events:
import Foundation
import UIKit

class TransferConfirmViewController: UIViewController, KeyboardCapable {
    //MARK: - LIFE CYCLE
    override func viewWillAppear(animated: Bool) {
        super.viewWillAppear(animated)

        registerKeyboardNotifications()
    }

    override func viewWillDisappear(animated: Bool) {
        super.viewWillDisappear(animated)

        unregisterKeyboardNotifications()
    }

    //MARK: - NOTIFICATIONS
    //MARK: Keyboard
    func keyboardWillShow(notification: NSNotification) {
        let keyboardHeight = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).CGRectValue().height
        let animationDuration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        performKeyboardShowFullViewAnimation(withKeyboardHeight: keyboardHeight, andDuration: animationDuration)
    }

    func keyboardWillHide(notification: NSNotification) {
        let animationDuration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        performKeyboardHideFullViewAnimation(withDuration: animationDuration)
    }
}

Now your UIViewController will respond to keyboard events and will animate in consequence.
Note: If you want a custom animation instead of push or pull the view, you must define custom methods on KeyboardAnimatable protocol or perform them on KeyboardCapable functions. It's up to you.

A: Just add this to you pod file -> pod 'IQKeyboardManager'
Thats it, handles all of keyboard, and scrollviews and everything!
You dont need to code anything, could not find a better solution!
It has an extension, which handles textfields display, screen shifting, next and previous arrows if there are multiple text fields.
It also has a custom done button, which can be removed.
Link -> https://github.com/hackiftekhar/IQKeyboardManager

A: A much, much more elegant solution is to use a UIView subclass (though this isn't always appropriate) and recalculate all your subviews on a parent's frame change (and be smart: only recalculate them if the new frame size has changed, i.e. use CGRectEqualToRect to compare the new frame when you override setFrame and BEFORE you call [super setFrame:frame_]).  The only catch to this is that the UIViewController you intend to use should probably listen to keyboard events (or, you could do it in the UIView itself, for handy encapsulation).  But only the UIKeyboardWillShowNotification and UIKeyboardWillHideNotification.  This is just so it will look smooth (if you wait for CG to call it, you will get a moment of choppiness).
This has the advantage of building a UIView subclass that does the right thing, anyway.
The naive implementation would be to override drawRect: (don't), a better one would be to just use layoutSubviews (and then in the UIViewController, or whatnot you can call [view setNeedsLayout] in a SINGLE method that is called for either show or hide).
This solution gets away from hardcoding a keyboard offset (which will change if they are not in split, etc) and also means that your view could be a subview of many other views and still respond properly.
Don't hardcode something like that unless there is no other solution.  The OS gives you enough info, if you've done things right, that you just need to redraw intelligently (based on your new frame size).  This is much cleaner and the way you should do things.  (There may be an even better approach, though.)
Cheers.

A: Here is my version using autolayout :
The idea is just to embed your view containing textfields / text view in an UIScrollView, set a constraint from the bottom to it's superview, make an outlet and update it's constant according to keyboard height using notifications.
This is based on Apple example here, and Apple technical note on UIScrollView using AutoLayout here.
1) Embed your View V in a UIScrollView S :
If you already set your constants and subviews, you can copy/paste your view and subviews in the ViewController's view, then embed it using Editor -> embed menu, and finally delete the copied views.)
2) Set the following constraints :

*

*S to top layout guide : 0

*S to bottom layout guide : 0

*S leading to superview : 0

*S trailing to superview : 0

*V top space to superview : 0

*V bottom space to superview : 0

*V trailing space to superview : 0

*V leading space to superview : 0

*V equal width to S

*Latest bottom V subview to superview : 20
3) Create an outlet from the latest constraint to your view controller
4) Use the following code :
@property (weak, nonatomic) IBOutlet NSLayoutConstraint *bottomSpaceToContentView;

// ...

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    // ...

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWasShown:)
                                                 name:UIKeyboardDidShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

#pragma mark - Handle keyboard

// Called when the UIKeyboardDidShowNotification is sent.
- (void)keyboardWasShown:(NSNotification*)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    self.bottomSpaceToContentView.constant = kBottomMargin + kbSize.height;
    [self.view layoutIfNeeded];
}

// Called when the UIKeyboardWillHideNotification is sent
- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    self.bottomSpaceToContentView.constant = kBottomMargin;
    [self.view layoutIfNeeded];
}

And tadaaaaa, it works !

A: It is very simple just put following code in your class and customise if you needed .
-(void)textFieldDidBeginEditing:(UITextField *)textField {
     //Show Keyboard
     self.view.frame = CGRectMake(self.view.frame.origin.x,
                              self.view.frame.origin.y-50,
                              self.view.frame.size.width,
                              self.view.frame.size.height);
}

-(void)textFieldDidEndEditing:(UITextField *)textField {
     // Hide keyboard
     self.view.frame = CGRectMake(self.view.frame.origin.x,
                              self.view.frame.origin.y+50,
                              self.view.frame.size.width,
                              self.view.frame.size.height);
}

A: One thing to consider is whether you ever want to use a UITextField on its own. I haven't come across any well-designed iPhone apps that actually use UITextFields outside of UITableViewCells.
It will be some extra work, but I recommend you implement all data entry views a table views. Add a UITextView to your UITableViewCells.

A: This document details a solution to this problem. Look at the source code under 'Moving Content That Is Located Under the Keyboard'. It's pretty straightforward.
EDIT: Noticed there's a wee glitch in the example. You will probably want to listen for UIKeyboardWillHideNotification instead of UIKeyboardDidHideNotification. Otherwise the scroll view behind of the keyboard will be clipped for the duration of the keyboard closing animation.

A: I was also having a lot of issue with a UIScrollView composing of multiple UITextFields, of which, one or more of them would get obscured by the keyboard when they are being edited.
Here are some things to consider if your UIScrollView is not properly scrolling.
1) Ensure that your contentSize is greater than the UIScrollView frame size.  The way to understand UIScrollViews is that the UIScrollView is like a viewing window on the content defined in the contentSize.  So when in order for the UIScrollview to scroll anywhere, the contentSize must be greater than the UIScrollView.  Else, there is no scrolling required as everything defined in the contentSize is already visible.  BTW, default contentSize = CGSizeZero.
2) Now that you understand that the UIScrollView is really a window into your "content", the way to ensure that the keyboard is not obscuring your UIScrollView's viewing "window" would be to resize the UIScrollView so that when the keyboard is present, you have the UIScrollView window sized to just the original UIScrollView frame.size.height minus the height of the keyboard.  This will ensure that your window is only that small viewable area.
3) Here's the catch:  When I first implemented this I figured I would have to get the CGRect of the edited textfield and call UIScrollView's scrollRecToVisible method.  I implemented the UITextFieldDelegate method textFieldDidBeginEditing with the call to the scrollRecToVisible method.  This actually worked with a strange side effect that the scrolling would snap the UITextField into position.  For the longest time I couldn't figure out what it was.  Then I commented out the textFieldDidBeginEditing Delegate method and it all work!!(???).  As it turned out, I believe the UIScrollView actually implicitly brings the currently edited UITextField into the viewable window implicitly.  My implementation of the UITextFieldDelegate method and subsequent call to the scrollRecToVisible was redundant and was the cause of the strange side effect.
So here are the steps to properly scroll your UITextField in a UIScrollView into place when the keyboard appears.
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.

- (void)viewDidLoad
{
    [super viewDidLoad];

    // register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification
                                               object:self.view.window];
    // register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillHide:)
                                                 name:UIKeyboardWillHideNotification
                                               object:self.view.window];
    keyboardIsShown = NO;
    //make contentSize bigger than your scrollSize (you will need to figure out for your own use case)
    CGSize scrollContentSize = CGSizeMake(320, 345);
    self.scrollView.contentSize = scrollContentSize;
}

- (void)keyboardWillHide:(NSNotification *)n
{
    NSDictionary* userInfo = [n userInfo];

    // get the size of the keyboard
    CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;

    // resize the scrollview
    CGRect viewFrame = self.scrollView.frame;
    // I'm also subtracting a constant kTabBarHeight because my UIScrollView was offset by the UITabBar so really only the portion of the keyboard that is leftover pass the UITabBar is obscuring my UIScrollView.
    viewFrame.size.height += (keyboardSize.height - kTabBarHeight);

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [self.scrollView setFrame:viewFrame];
    [UIView commitAnimations];

    keyboardIsShown = NO;
}

- (void)keyboardWillShow:(NSNotification *)n
{
    // This is an ivar I'm using to ensure that we do not do the frame size adjustment on the `UIScrollView` if the keyboard is already shown.  This can happen if the user, after fixing editing a `UITextField`, scrolls the resized `UIScrollView` to another `UITextField` and attempts to edit the next `UITextField`.  If we were to resize the `UIScrollView` again, it would be disastrous.  NOTE: The keyboard notification will fire even when the keyboard is already shown.
    if (keyboardIsShown) {
        return;
    }

    NSDictionary* userInfo = [n userInfo];

    // get the size of the keyboard
    CGSize keyboardSize = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;

    // resize the noteView
    CGRect viewFrame = self.scrollView.frame;
    // I'm also subtracting a constant kTabBarHeight because my UIScrollView was offset by the UITabBar so really only the portion of the keyboard that is leftover pass the UITabBar is obscuring my UIScrollView.
    viewFrame.size.height -= (keyboardSize.height - kTabBarHeight);

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [self.scrollView setFrame:viewFrame];
    [UIView commitAnimations];
    keyboardIsShown = YES;
}

*

*Register for the keyboard notifications at viewDidLoad

*Unregister for the keyboard nofitications at viewDidUnload

*Ensure that the contentSize is set and greater than your UIScrollView at viewDidLoad

*Shrink the UIScrollView when the keyboard is present

*Revert back the UIScrollView when the keyboard goes away.

*Use an ivar to detect if the keyboard is already shown on the screen since the keyboard notifications are sent each time a UITextField is tabbed even if the keyboard is already present to avoid shrinking the UIScrollView when it's already shrunk
One thing to note is that the UIKeyboardWillShowNotification will fire even when the keyboard is already on the screen when you tab on another UITextField.  I took care of this by using an ivar to avoid resizing the UIScrollView when the keyboard is already on the screen.  Inadvertently resizing the UIScrollView when the keyboard is already there would be disastrous!
Hope this code saves some of you a lot of headache.

A: You can do by using textfield delegate methods also. Check below code. It's working for me when placed textfield on scroll view.
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
     if(textField == answer)
    {
         CGPoint cPoint = textField.frame.origin;
         [scrollView setContentOffset:CGPointMake(0, cPoint.y - 100) animated:YES];
    }
}

Note: You have to change cPoint.y - 100 value according to your view.

A: here is a UITextfield (and other similar fields) category that i made that will make the textfield avoid the keyboard, you should be able to drop this in your view controller as is and it should work. It moves the entire screen up so the current textfield is above the keyboard with animations
#import "UIView+avoidKeyboard.h"
#import "AppDelegate.h"

@implementation UIView (avoidKeyboard)

- (void) becomeFirstResponder {

if(self.isFirstResponder)
    return;

[super becomeFirstResponder];

if ([self isKindOfClass:[UISearchBar class]] ||
    [self isKindOfClass:[UITextField class]] ||
    [self isKindOfClass:[UITextView class]])
{
    AppDelegate *appDelegate    = [UIApplication sharedApplication].delegate;

    CGRect screenBounds         = appDelegate.window.frame;

    CGFloat keyboardHeight;
    CGFloat keyboardY;
    CGFloat viewsLowestY;
    CGPoint origin              = [self.superview convertPoint:self.frame.origin toView:appDelegate.window]; //get this views origin in terms of the main screens bounds

    if(UIInterfaceOrientationIsPortrait([[UIApplication sharedApplication] statusBarOrientation])){ //the window.frame doesnt take its orientation into account so if its sideways we must use the x value of the origin instead of the y
        keyboardHeight          = 216;
        keyboardY               = screenBounds.size.height  - keyboardHeight; //find the keyboards y coord relative to how much the main window has moved up
        viewsLowestY            = origin.y + self.frame.size.height; //find the lowest point of this view
    }
    else {
        keyboardHeight          = 162;
        keyboardY               = screenBounds.size.width  - keyboardHeight;
        viewsLowestY            = origin.x + self.frame.size.height;
    }

    CGFloat difference          = viewsLowestY - keyboardY + 20; //find if this view overlaps with the keyboard with some padding

    if (difference > 0){ //move screen up if there is an overlap

        [UIView animateWithDuration:0.3 delay:0.0 options:UIViewAnimationOptionBeginFromCurrentState animations:^{

            CGRect frame = appDelegate.window.frame;

            if(UIInterfaceOrientationIsPortrait([[UIApplication sharedApplication] statusBarOrientation])){
                frame.origin.y -= difference;
            }
            else {
                frame.origin.x -= difference;
            }
            appDelegate.window.frame = frame;
        }
        completion:nil];
    }
}
}

//look at appDelegate to see when the keyboard is hidden

@end

In your appDelegate add this function
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardHides:) name:UIKeyboardWillHideNotification object:nil]; //add in didFinishLaunchingWithOptions

...

- (void)keyboardHides:(NSNotification *)notification
{
    [UIView animateWithDuration:0.3 animations:^{
        [window setFrame: CGRectMake(0, 0, window.frame.size.width, window.frame.size.height)];
    } completion:nil];
}

A: There are many answers available telling the approach. I took the same approach but the implementation isn't good.
Here is the base Idea . I made modifications to keyboardWasShown method.
{
// Obtain keyboard Info
NSDictionary* info = [notification userInfo];
CGRect keyboardRect = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue];
keyboardRect = [self.view convertRect:keyboardRect fromView:nil];

// Obtain ScrollView Info w.r.t. top View
CGRect scrollViewRect = [self.view convertRect:self.scrollView.frame fromView:nil];

// Depending upon your screen Ui, Scroll View's bottom edge might be at some offset from screen's bottom
// Calculate the exact offset
int scrollViewBottomOffset = self.view.frame.size.height - (scrollViewRect.origin.y + scrollViewRect.size.height);
int heightToBeAdjusted = keyboardRect.size.height - scrollViewBottomOffset;

// We may also need to consider the Insets if already present with ScrollView. Let's keep it simple for now
// But we should store these, so that we can restore the Insets when Keyboard is gone
// origInsets = self.scrollView.contentInset;

// Set the new Insets for ScrollView
UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, heightToBeAdjusted, 0.0);
self.scrollView.contentInset = contentInsets;
self.scrollView.scrollIndicatorInsets = contentInsets;

// Visible frame (not overlapped by Keyboard)
CGRect visibleFrame = self.view.frame;
visibleFrame.size.height -= keyboardRect.size.height;

// Get the Rect for Textfield w.r.t self.view
CGRect activeFieldFrame = self.activeField.frame;
activeFieldFrame = [self.view convertRect:activeFieldFrame fromView:self.scrollView];

// Check if the TextField is Visible or not
if (!CGRectContainsRect(visibleFrame, activeFieldFrame) ) {
    // Scroll to make it visible but for scrolling use the activeField frame w.r.t. to scroll View
    [self.scrollView scrollRectToVisible:self.activeField.frame animated:YES];
}

}
And add this method to initialize the activeField
- (IBAction)textFieldDidBeginEditing:(UITextField *)sender
{
self.activeField = sender;
}

A: https://github.com/michaeltyson/TPKeyboardAvoiding
 download this file and add custom class as this in your table view it will manage all things for you don't need to do any thing.
it has many option you can check it out for other also ,this is all you need to avoid keyboard

A: This is offset calculation independent from device. Gets the overlapped height between keyboard and textfield:
func keyboardShown(notification: NSNotification) {
    let info  = notification.userInfo!
    let value: AnyObject = info[UIKeyboardFrameEndUserInfoKey]!

    let rawFrame = value.CGRectValue
    let keyboardFrame = view.convertRect(rawFrame, fromView: nil)

    let screenHeight = UIScreen.mainScreen().bounds.size.height;
    let Ylimit = screenHeight - keyboardFrame.size.height
    let textboxOriginInSuperview:CGPoint = self.view.convertPoint(CGPointZero, fromCoordinateSpace: lastTextField!)

    self.keyboardHeight = (textboxOriginInSuperview.y+self.lastTextField!.frame.size.height) - Ylimit

    if(self.keyboardHeight>0){
        self.animateViewMoving(true, moveValue: keyboardHeight!)
    }else{
        keyboardHeight=0
    }
}

keyBoardHeight is the offset.

A: A much simpler yet generalised way just like apple does by takes keypads's height into consideration which is greatly helpful when we are using custom toolbar on top of keyboard.
though apple's approach here has got few issues.
Here is my approach (Slightly modified apple's way) -
// UIKeyboardDidShowNotification
- (void)keyboardWasShown:(NSNotification*)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
    self.scrollView.contentInset = contentInsets;
    self.scrollView.scrollIndicatorInsets = contentInsets;
}

// UIKeyboardWillHideNotification
- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    self.scrollView.contentInset = contentInsets;
    self.scrollView.scrollIndicatorInsets = contentInsets;
}

A: I know this is too late but I wanted to share with the future visitors especially my way of doing it. Many good methods were shared but I didn't like how the UI becomes totally bad. There's a simple method which involves two parts:-

*

*Add the TextField and, whatever you want it to be floating above the keyboard while editing, to a view so they become children of the view. And then it will be easy to maintain the look and not to affect the UI badly.

*Use the great tool CGAffineTransform(TranslationX: x, TranslationY: y) to move the created view above the keyboard.
I know it seems very simple but it is really effective and neat.

A: Easiest solution found
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    [self animateTextField: textField up: YES];
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
    [self animateTextField: textField up: NO];
}

- (void) animateTextField: (UITextField*) textField up: (BOOL) up
{
    const int movementDistance = 80; // tweak as needed
    const float movementDuration = 0.3f; // tweak as needed

    int movement = (up ? -movementDistance : movementDistance);

    [UIView beginAnimations: @"anim" context: nil];
    [UIView setAnimationBeginsFromCurrentState: YES];
    [UIView setAnimationDuration: movementDuration];
    self.view.frame = CGRectOffset(self.view.frame, 0, movement);
    [UIView commitAnimations];
}

A: A little fix that works for many UITextFields:
#pragma mark UIKeyboard handling

#define kMin 150

-(void)textFieldDidBeginEditing:(UITextField *)sender
{
    if (currTextField) {
        [currTextField release];
    }
    currTextField = [sender retain];
    // Move the main view, so that the keyboard does not hide it.
    if (self.view.frame.origin.y + currTextField.frame.origin. y >= kMin) {
        [self setViewMovedUp:YES];
    }
}

// Method to move the view up/down whenever the keyboard is shown/dismissed
-(void)setViewMovedUp:(BOOL)movedUp
{
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3]; // If you want to slide up the view

    CGRect rect = self.view.frame;
    if (movedUp)
    {
        // 1. move the view's origin up so that the text field that will be hidden come above the keyboard
        // 2. increase the size of the view so that the area behind the keyboard is covered up.
        rect.origin.y = kMin - currTextField.frame.origin.y ;
    }
    else
    {
        // Revert back to the normal state.
        rect.origin.y = 0;
    }
    self.view.frame = rect;

    [UIView commitAnimations];
}

- (void)keyboardWillShow:(NSNotification *)notif
{
    // Keyboard will be shown now. Depending on which textfield is active, move up or move down the view appropriately

    if ([currTextField isFirstResponder] && currTextField.frame.origin.y + self.view.frame.origin.y >= kMin)
    {
        [self setViewMovedUp:YES];
    }
    else if (![currTextField isFirstResponder] && currTextField.frame.origin.y + self.view.frame.origin.y < kMin)
    {
        [self setViewMovedUp:NO];
    }
}

- (void)keyboardWillHide:(NSNotification *)notif
{
    // Keyboard will be shown now. Depending on which textfield is active, move up or move down the view appropriately
    if (self.view.frame.origin.y < 0 ) {
        [self setViewMovedUp:NO];
    }
}

- (void)viewWillAppear:(BOOL)animated
{
    // Register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification object:self.view.window];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:)
                                                 name:UIKeyboardWillHideNotification object:self.view.window];
}

- (void)viewWillDisappear:(BOOL)animated
{
    // Unregister for keyboard notifications while not visible.
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
}

A: RPDP's code successfully moves the text field out of the way of the keyboard. But when you scroll to the top after using and dismissing the keyboard, the top has been scrolled up out of the view. This is true for the Simulator and the device. To read the content at the top of that view, one has to reload the view.
Isn't his following code supposed to bring the view back down?
else
{
    // revert back to the normal state.
    rect.origin.y += kOFFSET_FOR_KEYBOARD;
    rect.size.height -= kOFFSET_FOR_KEYBOARD;
}

A: Please follow these steps.
1) Declare following variable in .h file.
  {
         CGFloat animatedDistance;
  }

2) Declare following constants in .m file.
  static const CGFloat KEYBOARD_ANIMATION_DURATION = 0.3;
  static const CGFloat MINIMUM_SCROLL_FRACTION = 0.2;
  static const CGFloat MAXIMUM_SCROLL_FRACTION = 0.8;
  static const CGFloat PORTRAIT_KEYBOARD_HEIGHT = 216;
  static const CGFloat LANDSCAPE_KEYBOARD_HEIGHT = 162;

3) Use UITextField delegate to move up/down keyboard.
  -(void) textFieldDidBeginEditing:(UITextField *)textField
  {
         if(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone)
         {
               CGRect textFieldRect = [self.view.window convertRect:textField.bounds fromView:textField];
               CGRect viewRect = [self.view.window convertRect:self.view.bounds fromView:self.view];

               CGFloat midline = textFieldRect.origin.y + 0.5 * textFieldRect.size.height;
               CGFloat numerator =
    midline - viewRect.origin.y
    - MINIMUM_SCROLL_FRACTION * viewRect.size.height;
               CGFloat denominator =
    (MAXIMUM_SCROLL_FRACTION - MINIMUM_SCROLL_FRACTION)
    * viewRect.size.height;
               CGFloat heightFraction = numerator / denominator;

               if (heightFraction < 0.0)
               {
                     heightFraction = 0.0;
               }
               else if (heightFraction > 1.0)
               {
                     heightFraction = 1.0;
               }

               UIInterfaceOrientation orientation =
    [[UIApplication sharedApplication] statusBarOrientation];
               if (orientation == UIInterfaceOrientationPortrait)
               {
                     animatedDistance = floor(PORTRAIT_KEYBOARD_HEIGHT * heightFraction);
               }
               else
               {
                     animatedDistance = floor(LANDSCAPE_KEYBOARD_HEIGHT * heightFraction);
               }

               CGRect viewFrame = self.view.frame;
               viewFrame.origin.y -= animatedDistance;

               [UIView beginAnimations:nil context:NULL];
               [UIView setAnimationBeginsFromCurrentState:YES];
               [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

               [self.view setFrame:viewFrame];

               [UIView commitAnimations];
       }
  }

  -(void) textFieldDidEndEditing:(UITextField *)textField
  {
       if(UI_USER_INTERFACE_IDIOM()==UIUserInterfaceIdiomPhone)
       {
             CGRect viewFrame = self.view.frame;
             viewFrame.origin.y += animatedDistance;

             [UIView beginAnimations:nil context:NULL];
             [UIView setAnimationBeginsFromCurrentState:YES];
             [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

             [self.view setFrame:viewFrame];

             [UIView commitAnimations];
       }
 }

A: I recently found myself in a similar scenario when working on a messaging app. I created a custom UIView that sticks to the top of the keyboard and does most of what you need automatically
MessageComposerView

(source: thegameengine.org)
The idea behind this project was to create something that functioned similar to the iMessage composition view AKA:

*

*sticks to top of keyboard and moves to bottom of screen when keyboard dismissed

*handles changes in text

*handles rotations

In order to resize/reconfigure your UIScrollView you'll want to use the following optional delegate method:
- (void)messageComposerFrameDidChange:(CGRect)frame withAnimationDuration:(float)duration;
It will be called whenever the frame is changed (resized, repositioned, rotated) and will also supply the animation duration. You can use this information to resize your UIScrollView's frame and content insets as needed.

A: A simple solution extending the UIViewController
https://github.com/damienromito/VisibleFormViewController

A: I've found this to be the best solution, follow the code below:
Attach the below to your Vertical Space - Bottom Layout Guide - TextField constraint.
@property (weak, nonatomic) IBOutlet NSLayoutConstraint *textViewBottomConst;

Second add observers for keyboard notifications.
- (void)observeKeyboard {
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}

Add this to your viewDidLoad
[self observeKeyboard];

Finally the methods that handles keyboard changes.
- (void)keyboardWillShow:(NSNotification *)notification {
//THIS WILL MAKE SURE KEYBOARD DOESNT JUMP WHEN OPENING QUICKTYPE/EMOJI OR OTHER KEYBOARDS.
kbHeight = 0;
height = 0;
self.textViewBottomConst.constant = height;
self.btnViewBottomConst.constant = height;

    NSDictionary *info = [notification userInfo];
    NSValue *kbFrame = [info objectForKey:UIKeyboardFrameEndUserInfoKey];

    NSTimeInterval animationDuration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    CGRect keyboardFrame = [kbFrame CGRectValue];

    CGRect finalKeyboardFrame = [self.view convertRect:keyboardFrame fromView:self.view.window];

    int kbHeight = finalKeyboardFrame.size.height;

    int height = kbHeight + self.textViewBottomConst.constant;

    self.textViewBottomConst.constant = height;

    [UIView animateWithDuration:animationDuration animations:^{
        [self.view layoutIfNeeded];
    }];
}

- (void)keyboardWillHide:(NSNotification *)notification {
    NSDictionary *info = [notification userInfo];

    NSTimeInterval animationDuration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];

    self.textViewBottomConst.constant = 10;

    [UIView animateWithDuration:animationDuration animations:^{
        [self.view layoutIfNeeded];
    }];
}

A: I wrap everything in one class. Just call these lines of code when your viewcontroller is loaded:
- (void)viewDidLoad {
    [super viewDidLoad];
    KeyboardInsetScrollView *injectView = [[KeyboardInsetScrollView alloc] init];
    [injectView injectToView:self.view withRootView:self.view];
}

Here is link of sample project:
https://github.com/caohuuloc/KeyboardInsetScrollView

A: Set Scrollview in view
  - (void)textFieldDidBeginEditing:(UITextField *)textField
    {
     CGPoint point;
    if(textField == txtEmail){
      // -90 is for my you can change as per your postion
      point = CGPointMake(0, textField.frame.origin.y - 90);
    }
    else if (textField == txtContact){
      point = CGPointMake(0, textField.frame.origin.y - 90);
    }
      [scrollV setContentOffset:point animated:YES];
    }

A: - SwiftUI
Show only the active TextField
This will move the view enough just to avoid hiding only the active TextField.

struct ContentView: View {
    @ObservedObject private var kGuardian = KeyboardGuardian(textFieldCount: 3)
    @State private var name = Array<String>.init(repeating: "", count: 3)

    var body: some View {

        VStack {
            Group {
                Text("Some filler text").font(.largeTitle)
                Text("Some filler text").font(.largeTitle)
            }

            TextField("text #1", text: $name[0], onEditingChanged: { if $0 { self.kGuardian.showField = 0 } })
                .textFieldStyle(RoundedBorderTextFieldStyle())
                .background(GeometryGetter(rect: $kGuardian.rects[0]))

            TextField("text #2", text: $name[1], onEditingChanged: { if $0 { self.kGuardian.showField = 1 } })
                .textFieldStyle(RoundedBorderTextFieldStyle())
                .background(GeometryGetter(rect: $kGuardian.rects[1]))

            TextField("text #3", text: $name[2], onEditingChanged: { if $0 { self.kGuardian.showField = 2 } })
                .textFieldStyle(RoundedBorderTextFieldStyle())
                .background(GeometryGetter(rect: $kGuardian.rects[2]))

            }.offset(y: kGuardian.slide).animation(.easeInOut(duration: 0.25))
    }

}

Show all TextFields
This moves all textField up, if the keyboard appears for any of them. But only if needed. If the keyboard doesn't hide the textfields, they will not move.

struct ContentView: View {
    @ObservedObject private var kGuardian = KeyboardGuardian(textFieldCount: 1)
    @State private var name = Array<String>.init(repeating: "", count: 3)

    var body: some View {

        VStack {
            Group {
                Text("Some filler text").font(.largeTitle)
                Text("Some filler text").font(.largeTitle)
            }

            TextField("enter text #1", text: $name[0])
                .textFieldStyle(RoundedBorderTextFieldStyle())

            TextField("enter text #2", text: $name[1])
                .textFieldStyle(RoundedBorderTextFieldStyle())

            TextField("enter text #3", text: $name[2])
                .textFieldStyle(RoundedBorderTextFieldStyle())
                .background(GeometryGetter(rect: $kGuardian.rects[0]))

        }.offset(y: kGuardian.slide).animation(.easeInOut(duration: 0.25))
    }

}

Both examples use the same common codes: GeometryGetter and KeyboardGuardian Inspired by @kontiki
GeometryGetter
This is a view that absorbs the size and position of its parent view. Encapsulate description here In order to achieve that, it is called inside the .background modifier. This is a very powerful modifier, not just a way to decorate the background of a view. When passing a view to .background(MyView()), MyView is getting the modified view as the parent. Using GeometryReader is what makes it possible for the view to know the geometry of the parent.
For example: Text("hello").background(GeometryGetter(rect: $bounds)) will fill variable bounds, with the size and position of the Text view, and using the global coordinate space.
struct GeometryGetter: View {
    @Binding var rect: CGRect

    var body: some View {
        GeometryReader { geometry in
            Group { () -> AnyView in
                DispatchQueue.main.async {
                    self.rect = geometry.frame(in: .global)
                }

                return AnyView(Color.clear)
            }
        }
    }
}

Note that the DispatchQueue.main.async is to avoid the possibility of modifying the state of the view while it is being rendered.
KeyboardGuardian
The purpose of KeyboardGuardian, is to keep track of keyboard show/hide events and calculate how much space the view needs to be shifted.
Note that it refreshes the slide, when the user tabs from one field to another*
import SwiftUI
import Combine

final class KeyboardGuardian: ObservableObject {
    public var rects: Array<CGRect>
    public var keyboardRect: CGRect = CGRect()

    // keyboardWillShow notification may be posted repeatedly,
    // this flag makes sure we only act once per keyboard appearance
    public var keyboardIsHidden = true

    @Published var slide: CGFloat = 0

    var showField: Int = 0 {
        didSet {
            updateSlide()
        }
    }

    init(textFieldCount: Int) {
        self.rects = Array<CGRect>(repeating: CGRect(), count: textFieldCount)

        NotificationCenter.default.addObserver(self, selector: #selector(keyBoardWillShow(notification:)), name: UIResponder.keyboardWillShowNotification, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(keyBoardDidHide(notification:)), name: UIResponder.keyboardDidHideNotification, object: nil)

    }

    deinit {
        NotificationCenter.default.removeObserver(self)
    }

    @objc func keyBoardWillShow(notification: Notification) {
        if keyboardIsHidden {
            keyboardIsHidden = false
            if let rect = notification.userInfo?["UIKeyboardFrameEndUserInfoKey"] as? CGRect {
                keyboardRect = rect
                updateSlide()
            }
        }
    }

    @objc func keyBoardDidHide(notification: Notification) {
        keyboardIsHidden = true
        updateSlide()
    }

    func updateSlide() {
        if keyboardIsHidden {
            slide = 0
        } else {
            let tfRect = self.rects[self.showField]
            let diff = keyboardRect.minY - tfRect.maxY

            if diff > 0 {
                slide += diff
            } else {
                slide += min(diff, 0)
            }

        }
    }
}

A: It's actually best just to use Apple's implementation, as provided in the docs. However, the code they provide is faulty. Replace the portion found in keyboardWasShown: just below the comments to the following:
NSDictionary* info = [aNotification userInfo];
CGRect keyPadFrame=[[UIApplication sharedApplication].keyWindow convertRect:[[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue] fromView:self.view];
CGSize kbSize =keyPadFrame.size;
CGRect activeRect=[self.view convertRect:activeField.frame fromView:activeField.superview];
CGRect aRect = self.view.bounds;
aRect.size.height -= (kbSize.height);

CGPoint origin =  activeRect.origin;
origin.y -= backScrollView.contentOffset.y;
if (!CGRectContainsPoint(aRect, origin)) {
    CGPoint scrollPoint = CGPointMake(0.0,CGRectGetMaxY(activeRect)-(aRect.size.height));
    [backScrollView setContentOffset:scrollPoint animated:YES];
}

The problems with Apple's code are these:
(1) They always calculate if the point is within the view's frame, but it's a ScrollView, so it may already have scrolled and you need to account for that offset:
origin.y -= scrollView.contentOffset.y

(2) They shift the contentOffset by the height of the keyboard, but we want the opposite (we want to shift the contentOffset by the height that is visible on the screen, not what isn't):
activeField.frame.origin.y-(aRect.size.height)

A: In textFieldDidBeginEditting and in textFieldDidEndEditing call the function [self animateTextField:textField up:YES] like so:
-(void)textFieldDidBeginEditing:(UITextField *)textField
{
    [self animateTextField:textField up:YES];
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
    [self animateTextField:textField up:NO];
}

-(void)animateTextField:(UITextField*)textField up:(BOOL)up
{
    const int movementDistance = -130; // tweak as needed
    const float movementDuration = 0.3f; // tweak as needed

    int movement = (up ? movementDistance : -movementDistance);

    [UIView beginAnimations: @"animateTextField" context: nil];
    [UIView setAnimationBeginsFromCurrentState: YES];
    [UIView setAnimationDuration: movementDuration];
    self.view.frame = CGRectOffset(self.view.frame, 0, movement);
    [UIView commitAnimations];
}

I hope this code will help you.
Swift 5
func animateTextField(textField: UITextField, up: Bool) {

    let movementDistance: CGFloat = -130
    let movementDuration: Double = 0.3

    var movement:CGFloat = 0
    if up {
        movement = movementDistance
    } else {
        movement = -movementDistance
    }

    UIView.animate(withDuration: movementDuration, delay: 0, options: [.beginFromCurrentState]) {
        self.view.frame = self.view.frame.offsetBy(dx: 0, dy: movement)
    }
}

func textFieldDidBeginEditing(_ textField: UITextField) {
    animateTextField(textField: textField, up: true)
}

func textFieldDidEndEditing(_ textField: UITextField) {
    animateTextField(textField: textField, up: false)
}

A: To bring back to original view state, add:
-(void)textFieldDidEndEditing:(UITextField *)sender

{
    //move the main view, so that the keyboard does not hide it.
    if  (self.view.frame.origin.y < 0)
    {
        [self setViewMovedUp:NO];
    }
}

A: I'm not sure if moving the view up is the correct approach. I did it in a different way, resizing the UIScrollView. I explained it in details in a little article.

A: Try this short trick.
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    [self animateTextField: textField up: YES];
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
    [self animateTextField: textField up: NO];
}

- (void) animateTextField: (UITextField*) textField up: (BOOL) up
{
    const int movementDistance = textField.frame.origin.y / 2; // tweak as needed
    const float movementDuration = 0.3f; // tweak as needed

    int movement = (up ? -movementDistance : movementDistance);

    [UIView beginAnimations: @"anim" context: nil];
    [UIView setAnimationBeginsFromCurrentState: YES];
    [UIView setAnimationDuration: movementDuration];
    self.view.frame = CGRectOffset(self.view.frame, 0, movement);
    [UIView commitAnimations];
}

A: Lots of answers here, but this works and is much shorter than most:
- (void)textFieldDidBeginEditing:(UITextField *)sender
{
    UIScrollView *scrollView = (UIScrollView *)self.view; // assuming this method is pasted into the UIScrollView's controller
    const double dontHardcodeTheKeyboardHeight = 162;
    double textY = [sender convertPoint:CGPointMake(0, 0) toView:scrollView].y;
    if (textY - scrollView.contentOffset.y + sender.frame.size.height > self.view.frame.size.height - dontHardcodeTheKeyboardHeight)
        [scrollView setContentOffset:CGPointMake(0.0, textY - 10) animated:YES];
}

A: Just found this class:
https://github.com/OliverLetterer/SLScrollViewKeyboardSupport
And so far it works very well on iPhone, including animations & the correct offset.
To use it, simply add to viewDidLoad:
self.support = [[SLScrollViewKeyboardSupport alloc] initWithScrollView:self.scrollView];

A: *

*If the text field is not completely or partially hidden  then we should not change anything.

*We should calculate exact intersection area(keyboard's frame and textfield's frame) which is hidden and then we should change the view's frame.

*Here i am giving a complete example .
Declaring 3 varible

#define PADDING 10
@interface PKViewController ()
      @property (nonatomic, assign) CGRect originalViewFrame; //original view's frame
      @property (nonatomic, strong) UITextField *activeTextField; // current text field
      @property (nonatomic, assign) CGRect keyBoardRect; // covered area by keaboard
     @end

Store original frame
- (void)viewDidLoad {
    [super viewDidLoad];
    _originalViewFrame = self.view.frame;
}

Add your view controller as observer for keyboard notification
- (void)viewWillAppear:(BOOL)animated{
    [super viewWillAppear:animated];
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWasShown:)
                                                 name:UIKeyboardDidShowNotification
                                               object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillHide:)
                                                 name:UIKeyboardWillHideNotification
                                               object:nil];
}

Remove observer
- (void)viewWillDisappear:(BOOL)animated{
    [super viewWillDisappear:animated];
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

Store the area covered by the keyboard when it appears and set it to CGRectZero when it disappear
- (void)keyboardWasShown:(NSNotification *)notification{
    CGSize keyboardSize = [[[notification userInfo] objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
    _keyBoardRect = CGRectMake(0, _originalViewFrame.size.height - keyboardSize.height, keyboardSize.width, keyboardSize.height);
    [self moveTextFieldUP];

}
- (void) keyboardWillHide:(NSNotification *)notification{
    _keyBoardRect = CGRectZero;
    [self setDefaultFrame];
}

Store the active textfield
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField {
    _activeTextField = textField;
//When keyboard is already present but the textfield is hidden. Case:When return key of  keyboard makes the next textfield as first responder
    if (!CGRectIsEmpty(_keyBoardRect)) {
        [self moveTextFieldUP];
    }
    return YES;
}
- (BOOL)textFieldShouldReturn:(UITextField *)textField{
    [textField resignFirstResponder];
    return YES;
}

Now we should change the frame of the view
- (void)moveTextFieldUP{
    CGRect virtualTextFieldRect = CGRectMake(0, self.view.frame.origin.y, _activeTextField.frame.size.width, _activeTextField.frame.origin.y+_activeTextField.frame.size.height);
    if (CGRectIntersectsRect(_keyBoardRect, virtualTextFieldRect)) {
        CGRect intersectRect = CGRectIntersection(_keyBoardRect, virtualTextFieldRect);
        CGFloat newY = _originalViewFrame.origin.y - intersectRect.size.height;
        CGFloat newHeight = _originalViewFrame.size.height + intersectRect.size.height;
        CGRect newFrame = CGRectMake(0, newY-PADDING, _originalViewFrame.size.width, newHeight+PADDING);
        [UIView animateWithDuration:0.3 animations:^{
            [self.view setFrame:newFrame];
        }];

        NSLog(@"Intersect");
    }
}
- (void)setDefaultFrame {
    [UIView animateWithDuration:0.3 animations:^{
        [self.view setFrame:_originalViewFrame];
    }];
}

A: -(BOOL) textFieldShouldBeginEditing:(UITextField *)textField {

  [self slideUp];
   return YES;
}

-(BOOL) textFieldShouldEndEditing:(UITextField *)textField {

    [self slideDown];
   return YES;
}

#pragma mark - Slide Up and Down animation

- (void) slideUp {
    [UIView beginAnimations:nil context:nil];
    layoutView.frame = CGRectMake(0.0, -70.0, layoutView.frame.size.width, layoutView.frame.size.height);

    [UIView commitAnimations];
}

- (void) slideDown {
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDelay: 0.01];
    layoutView.frame = CGRectMake(0.0, 0.0, layoutView.frame.size.width, layoutView.frame.size.height);
    [UIView commitAnimations];
}

A: Simple solution and with latest animation api. Changing the origin.y by 215, you can customize it to whichever value works for you.
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    if (self.view.frame.origin.y >= 0) {

        [UIView animateWithDuration:0.5 animations:^{
           self.view.frame = CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y-215, self.view.frame.size.width, self.view.frame.size.height);
       }];
   }
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
    if (self.view.frame.origin.y < 0) {
        [UIView animateWithDuration:0.5 animations:^{
           self.view.frame = CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y+215, self.view.frame.size.width, self.view.frame.size.height);
        }];

    }
}

A: Please add these lines in text field delegate method to scroll up in iPad.
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    activeTextfield = textField;

    CGPoint pt;
    CGRect rc = [textField bounds];
    rc = [textField convertRect:rc toView:scrlView];
    pt = rc.origin;
    pt.x = 0;
    pt.y -= 100;

    [scrlView setContentOffset:pt animated:YES];

    scrlView.contentSize = CGSizeMake(scrlView.frame.size.width, button.frame.origin.y+button.frame.size.height + 8 + 370);
}

A: It can be done easily & automatically if that textfield is in a table's cell (even when the table.scrollable = NO).

*

*NOTE that: the position and size of the table must be reasonable.
e.g:

*

*if the y position of table is 100 counted from the view's bottom, then the 300 height keyboard will overlap the whole table.

*if table's height = 10, and the textfield in it must be scrolled up 100 when keyboard appears in order to be visible, then that textfield will be out of the table's bound.

A: Very lightweight solution could be using KeyboardAnimator.
project got the sample implementation, documentation is still in progress...
Appropriate usage ::
It's have a specific implementation for UITextField & UITextView
Limitation::
It's fully on objective-c, swift version will be available soon.

A: This will work Perfectly.The scroll view atmatically adjust by textfield position.i am sure you will feel good
static const CGFloat KEYBOARD_ANIMATION_DURATION = 0.25;
static const CGFloat MINIMUM_SCROLL_FRACTION = 0.2;
static const CGFloat MAXIMUM_SCROLL_FRACTION = 0.8;
static const CGFloat PORTRAIT_KEYBOARD_HEIGHT = 216;
static const CGFloat LANDSCAPE_KEYBOARD_HEIGHT = 162;
@interface LoginVC ()
{
  CGFloat animatedDistance;
   CGRect viewFrameKey;
}

 //In ViewDidLoad
   viewFrameKey=self.view.frame;

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
CGRect textFieldRect =
[self.view.window convertRect:textField.bounds fromView:textField];
CGRect viewRect =
[self.view.window convertRect:self.view.bounds fromView:self.view];
CGFloat midline = textFieldRect.origin.y + 0.5 * textFieldRect.size.height;
CGFloat numerator =
midline - viewRect.origin.y
- MINIMUM_SCROLL_FRACTION * viewRect.size.height;
CGFloat denominator =
(MAXIMUM_SCROLL_FRACTION - MINIMUM_SCROLL_FRACTION)
* viewRect.size.height;
CGFloat heightFraction = numerator / denominator;
if (heightFraction < 0.0)
{
    heightFraction = 0.0;
}
else if (heightFraction > 1.0)
{
    heightFraction = 1.0;
}
UIInterfaceOrientation orientation =
[[UIApplication sharedApplication] statusBarOrientation];
if (orientation == UIInterfaceOrientationPortrait ||
    orientation == UIInterfaceOrientationPortraitUpsideDown)
{
    animatedDistance = floor(PORTRAIT_KEYBOARD_HEIGHT * heightFraction);
}
else
{
    animatedDistance = floor(LANDSCAPE_KEYBOARD_HEIGHT * heightFraction);
}
CGRect viewFrame = self.view.frame;
viewFrame.origin.y -= animatedDistance;

[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

[self.view setFrame:viewFrame];

[UIView commitAnimations];
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationBeginsFromCurrentState:YES];
[UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];
[self.view setFrame:viewFrameKey];
[UIView commitAnimations];
}

A: I would like to extend the answer of @sumanthkodi.
As some people have stated, his approach doesn't work in newer implementations, because the UIView fails to move when you are using constraints.
I edited the code as follows (and ported to Swift 2.0) and hope that it helps some people:

1) Reference the vertical constraint of the view you would like to move up:
@IBOutlet var viewConstraint: NSLayoutConstraint!

Make sure you reference this var in your storyboard with the constraint.
2) Add the delegate and implement the listeners. This is the same implementation as before:
class YourViewController: UIViewController, UITextFieldDelegate {

    ...

    func textFieldDidBeginEditing(textField: UITextField) {
        animateTextField(textField, up: true)
    }

    func textFieldDidEndEditing(textField: UITextField) {
        animateTextField(textField, up: false)
    }

    ...

}

3) Add your animation method animateTextField to YourViewController class. Set the temporary constraint value as needed.
func animateTextField(textfield: UITextField, up: Bool) {

    let originalConstraint = 50
    let temporaryConstraint = 0
    let movementDuration = 0.3

    let constraint = CGFloat(up ? temporaryConstraint : originalConstraint)

    containerViewConstraint.constant = constraint
    UIView.animateWithDuration(movementDuration) {
        self.view.layoutIfNeeded()
    }

}

A: This can be simply achieved with below lines of code using constraints
- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(keyboardWillShow:)
                                                     name:UIKeyboardWillShowNotification
                                                   object:nil];
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(keyboardWillHide:)
                                                     name:UIKeyboardWillHideNotification
                                                   object:nil];
}

- (void)keyboardWillShow:(NSNotification *)notification {
    [self adjustTextViewByKeyboardState:YES keyboardInfo:[notification userInfo]];
}

- (void)keyboardWillHide:(NSNotification *)notification {
    [self adjustTextViewByKeyboardState:NO keyboardInfo:[notification userInfo]];
}

- (void)viewDidDisappear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    [super viewDidDisappear:animated];
}

- (void)adjustTextViewByKeyboardState:(BOOL)showKeyboard keyboardInfo:(NSDictionary *)info {
    CGRect keyboardFrame = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGFloat height = keyboardFrame.size.height;
    self.constraintToAdjust.constant = height;        UIViewAnimationCurve animationCurve = [info[UIKeyboardAnimationCurveUserInfoKey] unsignedIntegerValue];
    UIViewAnimationOptions animationOptions = UIViewAnimationOptionBeginFromCurrentState;
    if (animationCurve == UIViewAnimationCurveEaseIn) {
        animationOptions |= UIViewAnimationOptionCurveEaseIn;
    }
    else if (animationCurve == UIViewAnimationCurveEaseInOut) {
        animationOptions |= UIViewAnimationOptionCurveEaseInOut;
    }
    else if (animationCurve == UIViewAnimationCurveEaseOut) {
        animationOptions |= UIViewAnimationOptionCurveEaseOut;
    }
    else if (animationCurve == UIViewAnimationCurveLinear) {
        animationOptions |= UIViewAnimationOptionCurveLinear;
    }
    [UIView animateWithDuration:[[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue] delay:0 options:animationOptions animations:^{
        [self.view layoutIfNeeded];
    }                completion:nil];
}

A: Though this thread has got enough answers, I would like to suggest a much simpler yet generalised way just like apple does by takes keypads's height into consideration which is greatly helpful when we are using custom toolbar on top of keyboard.
though apple's approach here has got few issues.
Here is my approach (Slightly modified apple's way) -
// Called when the UIKeyboardDidShowNotification is sent.
- (void)keyboardWasShown:(NSNotification*)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, kbSize.height, 0.0);
    self.scrollView.contentInset = contentInsets;
    self.scrollView.scrollIndicatorInsets = contentInsets;
}

// Called when the UIKeyboardWillHideNotification is sent
- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    UIEdgeInsets contentInsets = UIEdgeInsetsZero;
    self.scrollView.contentInset = contentInsets;
    self.scrollView.scrollIndicatorInsets = contentInsets;
}

A: *

*Download TPKeyBoardAvoiding From this link: https://github.com/michaeltyson/TPKeyboardAvoiding.

*Expand the zipped folder and find TPKeyboardAvoiding folder.

*Select all .h and .m files and drop it to your project.Make sure copy items if needed is ticked.

*Drag and drop a UIScrollView to StoryBoard and associate with TPKeyboardAvoidingScrollView.

*Now you can add UI elements on the top of the scroll view. Note that this class detect the UI elements touches even after dragging the scrollView.

On Your ViewController:
@IBOutlet weak var usernameTextfield: UITextField!
@IBOutlet weak var passwordTextfield: UITextField!
@IBOutlet weak var loginScrollView: UIScrollView!

override func viewWillAppear(animated: Bool) {
        loginScrollView.scrollEnabled =  false
    }

Add TextField Delegates.
//MARK:- TEXTFIELD METHODS
func textFieldShouldReturn(textField: UITextField) -> Bool
{
    if (usernameTextfield.resignFirstResponder())
    {
        passwordTextfield.becomeFirstResponder()
    }
    textField.resignFirstResponder();
    loginScrollView!.setContentOffset(CGPoint.zero, animated: true);
    loginScrollView.scrollEnabled =  false
    return true
}
func textFieldDidBeginEditing(textField: UITextField)
{
    loginScrollView.scrollEnabled =  true

    if (textField.tag  == 1 && (device == "iPhone" || device == "iPhone Simulator" || device == "iPod touch"))
    {
        let scrollPoint:CGPoint = CGPointMake(0, passwordTextfield.frame.origin.y/6.4);
        loginScrollView!.setContentOffset(scrollPoint, animated: true);

    }
    else if (textField.tag  == 2 && (device == "iPhone" || device == "iPhone Simulator" || device == "iPod touch"))
    {
        let scrollPoint:CGPoint = CGPointMake(0, passwordTextfield.frame.origin.y/6.0);
        loginScrollView!.setContentOffset(scrollPoint, animated: true);
    }
}
func textFieldDidEndEditing(textField: UITextField)
{
    loginScrollView!.setContentOffset(CGPointZero,animated: true);
}

A: This piece of code will calculate how much need to move up based on the keyboard height and how deep the text field as gone. Remember to add delegate and inherit UITextFieldDelegate at your header.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    [_tbxUsername resignFirstResponder];
    [_tbxPassword resignFirstResponder];
}

- (void)textFieldDidBeginEditing:(UITextField *) textField
{
    [self animateTextField:textField up:YES];
}

- (void)textFieldDidEndEditing:(UITextField *) textField
{
    [self animateTextField:textField up:NO];
}

- (void) animateTextField: (UITextField*) textField up: (BOOL) up
{
    int animatedDistance;
    int moveUpValue = textField.frame.origin.y+ textField.frame.size.height;
    UIInterfaceOrientation orientation =
    [[UIApplication sharedApplication] statusBarOrientation];
    if (orientation == UIInterfaceOrientationPortrait ||
        orientation == UIInterfaceOrientationPortraitUpsideDown)
    {

        animatedDistance = 236-(460-moveUpValue-5);
    }
    else
    {
        animatedDistance = 182-(320-moveUpValue-5);
    }

    if(animatedDistance>0)
    {
        const int movementDistance = animatedDistance;
        const float movementDuration = 0.3f;
        int movement = (up ? -movementDistance : movementDistance);
        [UIView beginAnimations: nil context: nil];
        [UIView setAnimationBeginsFromCurrentState: YES];
        [UIView setAnimationDuration: movementDuration];
        self.view.frame = CGRectOffset(self.view.frame, 0, movement);
        [UIView commitAnimations];
    }
}

Delegate to add at ViewDidLoad
_tbxUsername.delegate = self;
_tbxPassword.delegate = self;

A: Try IQKeyboard library.
This will automatically move the text field's up.

A: Swift 3.0 version of Apples keyboard management code is here:
FloatingTF used in the code below is a Material design based textfield in iOS.
import UIKit
class SignupViewController: UIViewController, UITextFieldDelegate {

    //MARK: - IBOutlet:
@IBOutlet weak var emailTF: FloatingTF!
@IBOutlet weak var passwordTF: FloatingTF!
@IBOutlet weak var dobTF: FloatingTF!

@IBOutlet weak var scrollView: UIScrollView!

//MARK: - Variable:
var activeTextField: UITextField!

//MARK: - ViewController Lifecycle:
override func viewDidLoad() {
    super.viewDidLoad()
    emailTF.delegate = self
    passwordTF.delegate = self
    dobTF.delegate = self
}
override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)

    registerKeyboardNotifications()
}
override func viewWillDisappear(_ animated: Bool) {
    super.viewWillDisappear(animated)

   deRegisterKeyboardNotifications()
}

//MARK: - Keyboard notification observer Methods
fileprivate func registerKeyboardNotifications() {
    NotificationCenter.default.addObserver(self, selector: #selector(SignupViewController.keyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(SignupViewController.keyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}
fileprivate func deRegisterKeyboardNotifications() {
    NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillShow, object: self.view.window)
    NotificationCenter.default.removeObserver(self, name: .UIKeyboardDidHide, object: self.view.window)
}
func keyboardWillShow(notification: NSNotification) {

    let info: NSDictionary = notification.userInfo! as NSDictionary
    let value: NSValue = info.value(forKey: UIKeyboardFrameBeginUserInfoKey) as! NSValue
    let keyboardSize: CGSize = value.cgRectValue.size
    let contentInsets: UIEdgeInsets = UIEdgeInsetsMake(0.0, 0.0, keyboardSize.height, 0.0)
    scrollView.contentInset = contentInsets
    scrollView.scrollIndicatorInsets = contentInsets

    // If active text field is hidden by keyboard, scroll it so it's visible
    // Your app might not need or want this behavior.
    var aRect: CGRect = self.view.frame
    aRect.size.height -= keyboardSize.height
    let activeTextFieldRect: CGRect? = activeTextField?.frame
    let activeTextFieldOrigin: CGPoint? = activeTextFieldRect?.origin
    if (!aRect.contains(activeTextFieldOrigin!)) {
        scrollView.scrollRectToVisible(activeTextFieldRect!, animated:true)
    }    }

func keyboardWillHide(notification: NSNotification) {
    let contentInsets: UIEdgeInsets = .zero
    scrollView.contentInset = contentInsets
    scrollView.scrollIndicatorInsets = contentInsets
}

//MARK: - UITextField Delegate Methods
func textFieldShouldReturn(_ textField: UITextField) -> Bool {
    if textField == emailTF {
        passwordTF.becomeFirstResponder()
    }
    else if textField == passwordTF {
        dobTF.becomeFirstResponder()
    }
    else {
        self.view.endEditing(true)
    }
    return true
}

func textFieldDidBeginEditing(_ textField: UITextField) {
    activeTextField = textField
    scrollView.isScrollEnabled = true
}

func textFieldDidEndEditing(_ textField: UITextField) {
    activeTextField = nil
    scrollView.isScrollEnabled = false
}
}

A: Simple Solution For Scrollview with TextFields is below, No need any Constraints or active textfield  etc...
 override func viewWillAppear(_ animated: Bool){
        super.viewWillAppear(animated)
        registerForKeyboardNotifications();

    }
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        deregisterFromKeyboardNotifications();
    }
    //MARK:- KEYBOARD DELEGATE METHODS
        func registerForKeyboardNotifications(){
            //Adding notifies on keyboard appearing
            NotificationCenter.default.addObserver(self, selector: #selector(keyboardWasShown(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
            NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillBeHidden(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
        }
        func deregisterFromKeyboardNotifications(){
            //Removing notifies on keyboard appearing
            NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillShow, object: nil)
            NotificationCenter.default.removeObserver(self, name: NSNotification.Name.UIKeyboardWillHide, object: nil)
        }
        func keyboardWasShown(notification: NSNotification){

            var info = notification.userInfo!
            let keyboardSize = (info[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue.size
            var contentInset:UIEdgeInsets = self.scrRegister.contentInset
            contentInset.bottom = (keyboardSize?.height)!
            scrRegister.contentInset = contentInset

        }
        func keyboardWillBeHidden(notification: NSNotification)
        {
            var contentInset:UIEdgeInsets = self.scrRegister.contentInset
            contentInset.bottom = 0
            scrRegister.contentInset = contentInset

        }

A: Using IQKeyboardManager,
The UITextField and UITextView automatically scroll when keyboard appears.
Git link: https://github.com/hackiftekhar/IQKeyboardManager.
pod:
pod 'IQKeyboardManager' #iOS8 and later
pod 'IQKeyboardManager', '3.3.7' #iOS7

A: Swift 5
in viewDidLoad or viewDidAppear add addKeyboardObservers method.
fileprivate func addKeyboardObservers(){
    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)

    NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
}

fileprivate func removeKeyboardObservers(){
    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillHideNotification, object: nil)
    NotificationCenter.default.removeObserver(self, name: UIResponder.keyboardWillShowNotification, object: nil)
}

@objc fileprivate func keyboardWillHide(_ notification: Notification){
    if (window == nil) {return}
    guard let duration = (notification.userInfo?[UIResponder.keyboardAnimationDurationUserInfoKey] as? Double) else {return}

   scrollView.contentInset.bottom = .zero
}

@objc fileprivate func keyboardWillShow(_ notification: Notification){
    if (window == nil) {return}
    if UIApplication.shared.applicationState != .active { return }

    // keyboard height
    guard let height = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? CGRect)?.height else {return}
    // keyboard present animation duration
    guard let duration = (notification.userInfo?[UIResponder.keyboardAnimationDurationUserInfoKey] as? Double) else {return}

   scrollView.contentInset.bottom = height
}

don't forget remove observers on deinit or disappear
    self.removeKeyboardObservers()

A: There so many solutions, but I've spend some hours before it start works. So, I put this code here (just paste to the project, any modifications needn't):
@interface RegistrationViewController : UIViewController <UITextFieldDelegate>{
    UITextField* activeField;
    UIScrollView *scrollView;
}
@end

- (void)viewDidLoad
{
    [super viewDidLoad];

    scrollView = [[UIScrollView alloc] initWithFrame:self.view.frame];

    //scrool view must be under main view - swap it
    UIView* natView = self.view;
    [self setView:scrollView];
    [self.view addSubview:natView];

    CGSize scrollViewContentSize = self.view.frame.size;
    [scrollView setContentSize:scrollViewContentSize];

    [self registerForKeyboardNotifications];
}

- (void)viewDidUnload {
    activeField = nil;
    scrollView = nil;
    [self unregisterForKeyboardNotifications];
    [super viewDidUnload];
}

- (void)registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShown:)
                                                 name:UIKeyboardWillShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];

}

-(void)unregisterForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardWillShowNotification
                                                  object:nil];
    // unregister for keyboard notifications while not visible.
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardWillHideNotification
                                                  object:nil];
}

- (void)keyboardWillShown:(NSNotification*)aNotification
{
    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    CGRect frame = self.view.frame;
    frame.size.height -= kbSize.height;
    CGPoint fOrigin = activeField.frame.origin;
    fOrigin.y -= scrollView.contentOffset.y;
    fOrigin.y += activeField.frame.size.height;
    if (!CGRectContainsPoint(frame, fOrigin) ) {
        CGPoint scrollPoint = CGPointMake(0.0, activeField.frame.origin.y + activeField.frame.size.height - frame.size.height);
        [scrollView setContentOffset:scrollPoint animated:YES];
    }
}

- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
     [scrollView setContentOffset:CGPointZero animated:YES];
}

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    activeField = textField;
}

- (void)textFieldDidEndEditing:(UITextField *)textField
{
    activeField = nil;
}

-(BOOL) textFieldShouldReturn:(UITextField *)textField
{
    [textField resignFirstResponder];
    return YES;
}

P.S: I hope the code help somebody make desired effect quickly.
(Xcode 4.5)

A: @user271753
To get your view back to original add:
-(BOOL)textFieldShouldReturn:(UITextField *)textField{
   [textField resignFirstResponder];
   [self setViewMovedUp:NO];
   return YES;
}

A: It doesn't require a scroll view to be able to move the view frame.  You can change the frame of a viewcontroller's view so that the entire view moves up just enough to put the firstresponder text field above the keyboard.  When I ran into this problem I created a subclass of UIViewController that does this.  It observes for the keyboard will appear notification and finds the first responder subview and (if needed) it animates the main view upward just enough so that the first responder is above the keyboard.  When the keyboard hides, it animates the view back where it was.
To use this subclass make your custom view controller a subclass of GMKeyboardVC and it inherits this feature (just be sure if you implement viewWillAppear and viewWillDisappear they must call super).  The class is on github.

A: Swift 4 .
You Can Easily Move Up And Down UITextField Or UIView With UIKeyBoard With Animation

import UIKit

class ViewController: UIViewController, UITextFieldDelegate {

    @IBOutlet var textField: UITextField!
    @IBOutlet var chatView: UIView!

    override func viewDidLoad() {
        super.viewDidLoad()
        NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillChange), name: .UIKeyboardWillChangeFrame, object: nil)
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        textField.resignFirstResponder()
    }

    @objc func keyboardWillChange(notification: NSNotification) {

        let duration = notification.userInfo![UIKeyboardAnimationDurationUserInfoKey] as! Double
        let curve = notification.userInfo![UIKeyboardAnimationCurveUserInfoKey] as! UInt
        let curFrame = (notification.userInfo![UIKeyboardFrameBeginUserInfoKey] as! NSValue).cgRectValue
        let targetFrame = (notification.userInfo![UIKeyboardFrameEndUserInfoKey] as! NSValue).cgRectValue
        let deltaY = targetFrame.origin.y - curFrame.origin.y
        print("deltaY",deltaY)

        UIView.animateKeyframes(withDuration: duration, delay: 0.0, options: UIViewKeyframeAnimationOptions(rawValue: curve), animations: {
            self.chatView.frame.origin.y+=deltaY // Here You Can Change UIView To UITextField
        },completion: nil)
    }

    func textFieldShouldReturn(_ textField: UITextField) -> Bool {
        textField.resignFirstResponder()
        return true
    }

}

A: Just using TextFields:
1a) Using Interface Builder: Select All TextFields => Edit => Embed In => ScrollView
1b) Manually embed TextFields in UIScrollView called scrollView
2) Set UITextFieldDelegate
3) Set each textField.delegate = self; (or make connections in Interface Builder)
4) Copy / Paste:
- (void)textFieldDidBeginEditing:(UITextField *)textField {
    CGPoint scrollPoint = CGPointMake(0, textField.frame.origin.y);
    [scrollView setContentOffset:scrollPoint animated:YES];
}

- (void)textFieldDidEndEditing:(UITextField *)textField {
    [scrollView setContentOffset:CGPointZero animated:YES];
}

A: For Universal Solution, Here was my approach for implementing IQKeyboardManager.

Step1:- I Added global notifications of UITextField, UITextView, and UIKeyboard in a singleton class. I call it IQKeyboardManager.
Step2:- If found UIKeyboardWillShowNotification, UITextFieldTextDidBeginEditingNotification or UITextViewTextDidBeginEditingNotification notifications, I try to get topMostViewController instance from the UIWindow.rootViewController hierarchy. In order to properly uncover UITextField/UITextView on it, topMostViewController.view's frame needs to be adjusted.
Step3:- I calculated expected move distance of topMostViewController.view with respect to first responded UITextField/UITextView.
Step4:- I moved topMostViewController.view.frame up/down according to the expected move distance.
Step5:- If found UIKeyboardWillHideNotification, UITextFieldTextDidEndEditingNotification or UITextViewTextDidEndEditingNotification notification, I again try to get topMostViewController instance from the UIWindow.rootViewController hierarchy.
Step6:- I calculated disturbed distance of topMostViewController.view which needs to be restored to it's original position.
Step7:- I restored topMostViewController.view.frame down according to the disturbed distance.
Step8:- I instantiated singleton IQKeyboardManager class instance on app load, so every UITextField/UITextView in the app will adjust automatically according to the expected move distance.
That's all IQKeyboardManager do for you with NO LINE OF CODE really!! only need to drag and drop related source file to project. IQKeyboardManager also support Device Orientation, Automatic UIToolbar Management, KeybkeyboardDistanceFromTextField and much more than you think.

A: Here is the hack solution I came up with for a specific layout. This solution is similar to Matt Gallagher solution in that is scrolls a section into view. I am still new to iPhone development, and am not familiar with how the layouts work. Thus, this hack.
My implementation needed to support scrolling when clicking in a field, and also scrolling when the user selects next on the keyboard.
I had a UIView with a height of 775. The controls are spread out basically in groups of 3 over a large space. I ended up with the following IB layout.
UIView -> UIScrollView -> [UI Components]

Here comes the hack
I set the UIScrollView height to 500 units larger then the actual layout (1250). I then created an array with the absolute positions I need to scroll to, and a simple function to get them based on the IB Tag number.
static NSInteger stepRange[] = {
    0, 0, 0, 0, 0, 0, 0, 0, 0, 140, 140, 140, 140, 140, 410
};

NSInteger getScrollPos(NSInteger i) {
    if (i < TXT_FIELD_INDEX_MIN || i > TXT_FIELD_INDEX_MAX) {
        return 0 ;
    return stepRange[i] ;
}

Now all you need to do is use the following two lines of code in textFieldDidBeginEditing and textFieldShouldReturn (the latter one if you are creating a next field navigation)
CGPoint point = CGPointMake(0, getScrollPos(textField.tag)) ;
[self.scrollView setContentOffset:point animated:YES] ;

An example.
- (void) textFieldDidBeginEditing:(UITextField *)textField
{
    CGPoint point = CGPointMake(0, getScrollPos(textField.tag)) ;
    [self.scrollView setContentOffset:point animated:YES] ;
}

- (BOOL)textFieldShouldReturn:(UITextField *)textField {

    NSInteger nextTag = textField.tag + 1;
    UIResponder* nextResponder = [textField.superview viewWithTag:nextTag];

    if (nextResponder) {
        [nextResponder becomeFirstResponder];
        CGPoint point = CGPointMake(0, getScrollPos(nextTag)) ;
        [self.scrollView setContentOffset:point animated:YES] ;
    }
    else{
        [textField resignFirstResponder];
    }

    return YES ;
}

This method does not 'scroll back' as other methods do. This was not a requirement. Again this was for a fairly 'tall' UIView, and I did not have days to learn the internal layout engines.

A: As per the docs, as of iOS 3.0, the UITableViewController class automatically resizes and repositions its table view when there is in-line editing of text fields. I think it's not sufficient to put the text field inside a UITableViewCell as some have indicated.
From the docs:

A table view controller supports inline editing of table view rows;
  if, for example, rows have embedded text fields in editing mode, it
  scrolls the row being edited above the virtual keyboard that is
  displayed.

A:
Here I found the simplest solution to handle keypad.

You need to just copy-paste below sample code and change your textfield or any view which you want to move up.
Step-1

Just copy-paste below two method in your controller

- (void)registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWasShown:)
                                                 name:UIKeyboardDidShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];
}

- (void)deregisterFromKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardDidHideNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}

Step-2

register  & deregister Keypad Notifications in viewWillAppear and
  viewWillDisappear methods respectively.

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    [self registerForKeyboardNotifications];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [self deregisterFromKeyboardNotifications];
    [super viewWillDisappear:animated];
}

Step-3

Here comes the soul part, Just replace your textfield, and change
  height how much you want to move upside.

- (void)keyboardWasShown:(NSNotification *)notification
{
    NSDictionary* info = [notification userInfo];
    CGSize currentKeyboardSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    //you need replace your textfield instance here
    CGPoint textFieldOrigin = self.tokenForPlaceField.frame.origin;
    CGFloat textFieldHeight = self.tokenForPlaceField.frame.size.height;

    CGRect visibleRect = self.view.frame;
    visibleRect.size.height -= currentKeyboardSize.height;

    if (!CGRectContainsPoint(visibleRect, textFieldOrigin))
    {
        //you can add yor desired height how much you want move keypad up, by replacing "textFieldHeight" below

        CGPoint scrollPoint = CGPointMake(0.0, textFieldOrigin.y - visibleRect.size.height  + textFieldHeight); //replace textFieldHeight to currentKeyboardSize.height, if you want to move up with more height
        [self.scrollView setContentOffset:scrollPoint animated:YES];
    }
}

- (void)keyboardWillBeHidden:(NSNotification *)notification
{
    [self.scrollView setContentOffset:CGPointZero animated:YES];
}

Reference:
well, Please appreciate this guy, who shared this beautiful code snip, clean solution.
Hope this would be surly helpful someone out there.

A: *

*You will only need a ScrollView if the contents you have now do not fit in the iPhone screen. (If you are adding the ScrollView as the superview of the components just to make the TextField scroll up when keyboard comes up, then it's not needed.)

*The standard way to prevent the TextFields from being covered by the keyboard is to move the view up/down whenever the keyboard is shown.
Here is some sample code:
#define kOFFSET_FOR_KEYBOARD 80.0

-(void)keyboardWillShow {
    // Animate the current view out of the way
    if (self.view.frame.origin.y >= 0)
    {
        [self setViewMovedUp:YES];
    }
    else if (self.view.frame.origin.y < 0)
    {
        [self setViewMovedUp:NO];
    }
}

-(void)keyboardWillHide {
    if (self.view.frame.origin.y >= 0)
    {
        [self setViewMovedUp:YES];
    }
    else if (self.view.frame.origin.y < 0)
    {
        [self setViewMovedUp:NO];
    }
}

-(void)textFieldDidBeginEditing:(UITextField *)sender
{
    if ([sender isEqual:mailTf])
    {
        //move the main view, so that the keyboard does not hide it.
        if  (self.view.frame.origin.y >= 0)
        {
            [self setViewMovedUp:YES];
        }
    }
}

//method to move the view up/down whenever the keyboard is shown/dismissed
-(void)setViewMovedUp:(BOOL)movedUp
{
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3]; // if you want to slide up the view

    CGRect rect = self.view.frame;
    if (movedUp)
    {
        // 1. move the view's origin up so that the text field that will be hidden come above the keyboard
        // 2. increase the size of the view so that the area behind the keyboard is covered up.
        rect.origin.y -= kOFFSET_FOR_KEYBOARD;
        rect.size.height += kOFFSET_FOR_KEYBOARD;
    }
    else
    {
        // revert back to the normal state.
        rect.origin.y += kOFFSET_FOR_KEYBOARD;
        rect.size.height -= kOFFSET_FOR_KEYBOARD;
    }
    self.view.frame = rect;

    [UIView commitAnimations];
}

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    // register for keyboard notifications
    [[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardWillShow)
                                             name:UIKeyboardWillShowNotification
                                           object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardWillHide)
                                             name:UIKeyboardWillHideNotification
                                           object:nil];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    // unregister for keyboard notifications while not visible.
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                             name:UIKeyboardWillShowNotification
                                           object:nil];

    [[NSNotificationCenter defaultCenter] removeObserver:self
                                             name:UIKeyboardWillHideNotification
                                           object:nil];
}

A: I've put together a universal, drop-in UIScrollView, UITableView and even UICollectionView subclass that takes care of moving all text fields within it out of the way of the keyboard.
When the keyboard is about to appear, the subclass will find the subview that's about to be edited, and adjust its frame and content offset to make sure that view is visible, with an animation to match the keyboard pop-up. When the keyboard disappears, it restores its prior size.
It should work with basically any setup, either a UITableView-based interface, or one consisting of views placed manually.
Here' tis: solution for moving text fields out of the way of the keyboard

A: When UITextField is in a UITableViewCell scrolling should be setup automatically.
If it is not it is probably because of incorrect code/setup of the tableview.
For example when i reloaded my long table with one UITextField at the bottom as follows,
-(void) viewWillAppear:(BOOL)animated
{
   [self.tableview reloadData];
}

then my textfield at the bottom was obscured by the keyboard which appeared when I clicked inside the textfield.
To fix this I had to do this -
-(void) viewWillAppear:(BOOL)animated
{
    //add the following line to fix issue
    [super viewWillAppear:animated];
    [self.tableview reloadData];
}

A: Been searching for a good tutorial for beginners on the subject, found the best tutorial here.
In the MIScrollView.h example at the bottom of the tutorial be sure to put a space at
@property (nonatomic, retain) id backgroundTapDelegate;

as you see.

A: Use this third party you don't need to write even one line
https://github.com/hackiftekhar/IQKeyboardManager
download project and drag and drop IQKeyboardManager in your project.
If you find any issue please read README document.
Guys really its remove headache to manage keyboard.

A: Please follow these steps ,it might be helpful.
Put one view then put your textfield on that view and detect the event by delegate when your keyboard is coming up,at that time instant animate the view up(You can assign some position for that view also),then your view would be going up to that position.Do the same thing for animating the view down.
Thanks

A: its simple:-
In TextFieldDidBeginEditing:-
self.view.frame=CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y-150, self.view.frame.size.width, self.view.frame.size.height);

In TextFieldShouldEndEditing:-
self.view.frame=CGRectMake(self.view.frame.origin.x, self.view.frame.origin.y+150, self.view.frame.size.width, self.view.frame.size.height);

A: i am late a little bit. You should add scrollView on your viewController.
You must be implement below 2 method.
TextField delegate method.
    - (void)textFieldDidBeginEditing:(UIView *)textField {
    [self scrollViewForTextField:reEnterPINTextField];
}

And then call the below methon in delegate method.
 - (void)scrollViewForTextField:(UIView *)textField {
    NSInteger keyboardHeight = KEYBOARD_HEIGHT;

    if ([textField UITextField.class]) {
        keyboardHeight += ((UITextField *)textField).keyboardControl.activeField.inputAccessoryView.frame.size.height;
    }

    CGRect screenFrame = [UIScreen mainScreen].bounds;
    CGRect aRect = (CGRect){0, 0, screenFrame.size.width, screenFrame.size.height - ([UIApplication sharedApplication].statusBarHidden ? 0 : [UIApplication sharedApplication].statusBarFrame.size.height)};
    aRect.size.height -= keyboardHeight;
    CGPoint relativeOrigin = [UIView getOriginRelativeToScreenBounds:textField];
    CGPoint bottomPointOfTextField = CGPointMake(relativeOrigin.x, relativeOrigin.y + textField.frame.size.height);

    if (!CGRectContainsPoint(aRect, bottomPointOfTextField) ) {
        CGPoint scrollPoint = CGPointMake(0.0, bottomPointOfTextField.y -aRect.size.height);
        [contentSlidingView setContentOffset:scrollPoint animated:YES];
    }
}

A: I've developed a framework for my own need to solve this issue better, and made it public now. It's not just for UITextField and UITextView, It works for any custom UIView that adopts UITextInput protocol like UITextField and UITextView and offers many useful features. You can install it via Carthage, CocoaPods or Swift Package Manager.
ODScrollView GitHub
ODScrollView Medium

ODScrollView is just a UIScrollView that automatically moves editable text areas like UITextField and UITextView vertically depending on keyboard visibility to offer better user experience.

Features

*

*Automatically moves first responder UIViews that adopt the UITextInput protocol up/down when the keyboard appears/disappears, e.g., UITextField, UITextView, UISearchTextField or any custom UIView that adopts UITextInput protocol.

*

*Note that if UITextInput's frame does NOT fits the remaining area between ODScrollView and keyboard, then ODScrollView adjusts UITextInput based on cursor position instead of frame. In such cases, "trackTextInputCursor" feature can be used. Example

*Adjustment margin can be applied for each UITextInput seperately for .Top and .Bottom adjustment direction setting. 20 CGFloat by default.

*Adjustment can be enabled/disabled for each UITextInput seperately. true by default.

*Adjustment directon - .Top, .Center, .Bottom - can be applied for each UITextInput seperately. .Bottom by default. Example

*Adjustment options determines how ODScrollView adjusts. .Always by default.

*

*.Always : ODScrollView always adjusts the UITextInput which is placed anywhere in the ODScrollView regardless UITextInput overlaps or not with shown keyboard. Example

*.IfNeeded : ODScrollView only adjusts the UITextInput if it overlaps with the shown keyboard. Example

*Besides UIScrollView.keyboardDismissModes, the keyboard can be dismissed by tapping a UIView which is provided by ODScrollViewDelegate. After the keyboard is dismissed, ODScrollView can return its original position. nil and false by default. Example
Usage
1 - First thing you need to do is setting up ODScrollView and its content view properly. Since ODScrollView is just a UIScrollView, you can implement ODScrollView same way you do for UIScrollView. It's up to you to create ODScrollView by using storyboard or programmatically.
If you're creating ODScrollView programmatically, you can continue from step 4.

  Suggested way to create UIScrollView in Storyboard
- If you are using Content Layout Guide and Frame Layout Guide:
    1.1 - scrollView: Place UIScrollView anywhere you want to use.
    1.2 - contentView: Place UIView inside scrollView.
    1.3 - Set contentView's top, bottom, leading and trailing constraints to Content Layout Guide's constraints.
    1.4 - Set contentView's width equal to Frame Layout Guide's width.
    1.5 - Set contentView's height equal to Frame Layout Guide's height or set static height which is larger than scrollView's height.
    1.6 - Build your UI inside contentView.

- If you are NOT using Content Layout Guide and Frame Layout Guide:
    1.1 - scrollView: Place UIScrollView anywhere you want to use.
    1.2 - contentView: Place UIView inside scrollView.
    1.3 - Set contentView's top, bottom, leading and trailing constraints to 0.
    1.4 - Set contentView's width equal to scrollView's width.
    1.5 - Set contentView's height equal to scrollView's superview's height or set static height which is larger than scrollView's height.
    1.6 - Build your UI inside contentView.

2 - Change the scrollView's class from UIScrollView to ODScrollView in the identity inspector on Storyboard.
3 - Create IBOutlets for scrollView and contentView on ViewController.
4 - Call the following methods inside ViewDidLoad() on ViewController:
override func viewDidLoad() {
    super.viewDidLoad()

    //ODScrollView setup
    scrollView.registerContentView(contentView)
    scrollView.odScrollViewDelegate = self
}

5 - Optional: You still can use UIScrollView's features:
override func viewDidLoad() {
    super.viewDidLoad()

    //ODScrollView setup
    scrollView.registerContentView(contentView)
    scrollView.odScrollViewDelegate = self

    // UIScrollView setup
    scrollView.delegate = self // UIScrollView Delegate
    scrollView.keyboardDismissMode = .onDrag // UIScrollView keyboardDismissMode. Default is .none.

    UITextView_inside_contentView.delegate = self
}

6 - Adopt ODScrollViewDelegate from ViewController and decide ODScrollView options:
extension ViewController: ODScrollViewDelegate {

    // MARK:- State Notifiers: are responsible for notifiying ViewController about what is going on while adjusting. You don't have to do anything if you don't need them.

    // #Optional
    // Notifies when the keyboard showed.
    func keyboardDidShow(by scrollView: ODScrollView) {}

    // #Optional
    // Notifies before the UIScrollView adjustment.
    func scrollAdjustmentWillBegin(by scrollView: ODScrollView) {}

    // #Optional
    // Notifies after the UIScrollView adjustment.
    func scrollAdjustmentDidEnd(by scrollView: ODScrollView) {}

    // #Optional
    // Notifies when the keyboard hid.
    func keyboardDidHide(by scrollView: ODScrollView) {}

    // MARK:- Adjustment Settings

    // #Optional
    // Specifies the margin between UITextInput and ODScrollView's top or bottom constraint depending on AdjustmentDirection
    func adjustmentMargin(for textInput: UITextInput, inside scrollView: ODScrollView) -> CGFloat {
        if let textField = textInput as? UITextField, textField == self.UITextField_inside_contentView {
            return 20
        } else {
            return 40
        }
    }

    // #Optional
    // Specifies that whether adjustment is enabled or not for each UITextInput seperately.
    func adjustmentEnabled(for textInput: UITextInput, inside scrollView: ODScrollView) -> Bool {
        if let textField = textInput as? UITextField, textField == self.UITextField_inside_contentView {
            return true
        } else {
            return false
        }
    }

    // Specifies adjustment direction for each UITextInput. It means that  some of UITextInputs inside ODScrollView can be adjusted to the bottom, while others can be adjusted to center or top.
    func adjustmentDirection(selected textInput: UITextInput, inside scrollView: ODScrollView) -> AdjustmentDirection {
        if let textField = textInput as? UITextField, textField == self.UITextField_inside_contentView {
            return .bottom
        } else {
            return .center
        }
    }

    /**
     - Always : ODScrollView always adjusts the UITextInput which is placed anywhere in the ODScrollView.
     - IfNeeded : ODScrollView only adjusts the UITextInput if it overlaps with the shown keyboard.
     */
    func adjustmentOption(for scrollView: ODScrollView) -> AdjustmentOption {
        .Always
    }

    // MARK: - Hiding Keyboard Settings

    /**
     #Optional

     Provides a view for tap gesture that hides keyboard.

     By default, keyboard can be dismissed by keyboardDismissMode of UIScrollView.

     keyboardDismissMode = .none
     keyboardDismissMode = .onDrag
     keyboardDismissMode = .interactive

     Beside above settings:

     - Returning UIView from this, lets you to hide the keyboard by tapping the UIView you provide, and also be able to use isResettingAdjustmentEnabled(for scrollView: ODScrollView) setting.

     - If you return nil instead of UIView object, It means that hiding the keyboard by tapping is disabled.
     */
    func hideKeyboardByTappingToView(for scrollView: ODScrollView) -> UIView? {
        self.view
    }

    /**
     #Optional

     Resets the scroll view offset - which is adjusted before - to beginning its position after keyboard hid by tapping to the provided UIView via hideKeyboardByTappingToView.

     ## IMPORTANT:
     This feature requires a UIView that is provided by hideKeyboardByTappingToView().
     */
    func isResettingAdjustmentEnabled(for scrollView: ODScrollView) -> Bool {
        true
    }
}

7 - Optional: You can adjust the ODScrollView when the cursor overlaps with keyboard while typing in multiline UITextInput. trackTextInputCursor(for UITextInput) must be called by UITextInput functions that is fired while typing.
/**
## IMPORTANT:
This feature is not going to work unless textView is subView of _ODScrollView
*/
func textView(_ textView: UITextView, shouldChangeTextIn range: NSRange, replacementText text: String) -> Bool {
       _ODScrollView.trackTextInputCursor(for textView)
   return true
}

A: You don't need this amount of code just for a simple task. There is a CocoaPod called "IQKeyboardManager" that will achieve the task for you:
pod 'IQKeyboardManager'

Then use this code in AppDelegate before returning from didFinishLaunchingWithOptions:
IQKeyboardManager.shared().isEnabled = true
IQKeyboardManager.shared().shouldResignOnTouchOutside = true
IQKeyboardManager.shared().isEnableAutoToolbar = false

A: Got a reference from Dune Buggy's answer. To up-scroll view according to TextField's Position. Because the existing answer is scrolling the whole View of the screen instead, I need to scroll View according to the text field's frame.

*

*KeyBoardWillShow
@objc func keyboardWillShow(notification: NSNotification) {

    guard let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else {

        // if keyboard size is not available for some reason, don't do anything
        return
    }
    let keyboardFrame = keyboardSize

    let maxheightScreen = self.view.frame

    if (self.txtEmail.frame.origin.y + ((self.txtEmail.superview)!.frame.maxY) + keyboardSize.height) >= maxheightScreen.size.height{
        if self.view.frame.origin.y == 0 {
            self.view.frame.origin.y -= (keyboardFrame.height - (self.txtEmail.frame.maxY + 120)) // Here i added 120 additional height for my additional view space
        }
    }
}

*

*KeyboardWillHide
@objc func keyboardWillHide(notification: NSNotification) {

    guard let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue else {
        // if keyboard size is not available for some reason, don't do anything
        return
    }

    let keyboardFrame = keyboardSize

    if self.view.frame.origin.y != 0 {
        self.view.frame.origin.y += (keyboardFrame.height - (self.txtEmail.frame.maxY + 120))
    }
}

A: I didn't see this possibility here, so i'm adding it, since I tried the methods in the answers but hours later discovered there is a much easier way in XCode 5 in iOS6/7:
Use NSLayoutConstraints.
See: Autolayout Constraint - Keyboard
Here is my code:
.m file:
// Called when the UIKeyboardWillShowNotification is sent.
- (void)keyboardWillBeShown:(NSNotification*)aNotification
{
    NSLog(@"keyboardWillBeShown:");
    [self.PhoneNumberLabelOutlet setHidden:TRUE];
    CGFloat heightOfLabel = self.PhoneNumberLabelOutlet.frame.size.height;
    for( NSLayoutConstraint* thisConstraint in self.topElementsVerticalDistanceFromTopLayoutConstraint ) {
        thisConstraint.constant -= heightOfLabel;
    }

    NSDictionary* info = [aNotification userInfo];
    CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;

    CGFloat oldConstant = [self.SignInYConstraint constant];
    self.SignInYConstraint.constant = oldConstant + kbSize.height;
    [self.view setNeedsUpdateConstraints];

    NSTimeInterval duration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    [UIView animateWithDuration:duration animations:^{
        [self.view layoutIfNeeded];
    }];

}

.h file:
#import <UIKit/UIKit.h>

@interface SignInViewController : UIViewController {

    UITextField* _activeField;
}

- (void)signInCallback:(NSObject*)object;

@property (weak, nonatomic) IBOutlet UILabel *PhoneNumberLabelOutlet;

@property (weak, nonatomic) IBOutlet UIActivityIndicatorView *ActivityIndicatorOutlet;

@property (weak, nonatomic) IBOutlet UITextField *UserIDTextfieldOutlet;

@property (weak, nonatomic) IBOutlet UITextField *PasswordTextfieldOutlet;

@property (weak, nonatomic) IBOutlet UIButton *SignInButton;

@property (weak, nonatomic) IBOutlet NSLayoutConstraint *SignInYConstraint;

@property (strong, nonatomic) IBOutletCollection(NSLayoutConstraint) NSArray *topElementsVerticalDistanceFromTopLayoutConstraint;

@end

A: I found @DK_ to be the solution I started using. However, there is the assumption that the scrollView covers the entire view. That was not the case for me. I only wanted a scrollView in case the keyboard covered the lower textfield on my login screen. So my content view was the same size as my scroll view, which was smaller than the main view.
It also didn't account for landscapes, which is where I got into trouble to begin with. After playing around with it for several days, this is my keyboardWasShown: method.
- (void)keyboardWasShown:(NSNotification*)aNotification
{
    // A lot of the inspiration for this code came from http://stackoverflow.com/a/4837510/594602
    CGFloat height = 0;
    NSDictionary* info = [aNotification userInfo];

    CGRect kbFrameRect = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGRect kbBoundsRect = [self.view convertRect:kbFrameRect fromView:nil]; // Convert frame from window to view coordinates.

    CGRect scrollRect = scrollView.frame;
    CGRect intersect = CGRectIntersection(kbBoundsRect, scrollRect);

    if (!CGRectIsNull(intersect))
    {
        height = intersect.size.height;
        UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, height, 0.0);
        scrollView.contentInset = contentInsets;
        scrollView.scrollIndicatorInsets = contentInsets;
    }

    // Figure out what the view rectangle is for the scrollView
    CGPoint contentOffset = scrollView.contentOffset;
    CGRect visibleRect = CGRectOffset(scrollRect, contentOffset.x, contentOffset.y);    // I'm not 100% sure if this is needed/right. My scrollView was always at the top in testing.
    visibleRect.size.height -= height;
    CGRect activeRect = activeField.frame;

    if (!CGRectContainsRect(visibleRect, activeRect))
    {
        [self.scrollView scrollRectToVisible:activeField.frame animated:YES];
    }
}

I also had some difficulties getting to to work with auto layout. If I don't have the layouts done correctly, I don't get the scrolling I expected. One thing that made life much easier was to place all of the items that were to be scrolling into a single view, and placed that as the only item in the scroll view. I called that single view the "content view".
I think the key part was that the content view had a set width and height. This allowed the scroll view to know exactly how much content it had to deal with. This goes a little backwards from usual layouts. Normally the views are trying to take as much room as possible. With the contents of a scroll view, you are trying to get the view to confine itself as much as possible. The content view allows you to put a stop to that. So I gave mine a height of 248, and used the standard screen width of 320 as my width.
The layouts that eventually worked for me were these:

*

*Scroll View to super view: Basically I gave constraints to the top, left and right.

*

*Horizontal Space - View - Scroll View (0)

*Vertical Space - View - Scroll View (0)

*Horizontal Space - Scroll View - View (0)

*Scroll View height: I set the scroll view with a constant height. I don't know if this was truly necessary, but it got the bounds of the scroll view itself.

*

*Height - (248) - Scroll View

*The content view to the scroll view: I gave constants to all sides, the top, left, bottom and right.

*

*Vertical Space - View - Scroll View (0)

*Vertical Space - Scroll View - View (0)

*Horizontal Space - View - Scroll View (0)

*Horizontal Space - Scroll View - View (0)

*The dimensions of the content view.

*

*Height - (248) - View

*Width - (320) - View

A: in (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
if (textField.frame.origin.y > self.view.frame.size.height - 216)
    {
        if (screenHeight>500)
            scrollView.contentSize = CGSizeMake(0.0, scrollView.contentSize.height + 100);
        else
            scrollView.contentSize = CGSizeMake(0.0, scrollView.contentSize.height + 216);
        CGPoint scrollPoint = CGPointMake(0.0,(textField.frame.origin.y - (self.view.frame.size.height - 216 - textField.frame.size.height - 20)));
        [scrollView setContentOffset:scrollPoint animated:YES];
    }
    [scrollView setScrollEnabled:YES];

when resigning keyBoard you need to write bellow code
scrollView.contentSize = CGSizeMake(0.0, 640);
CGPoint scrollPoint = CGPointMake(0.0,0.0);
[scrollView setContentOffset:scrollPoint animated:YES];

A: I use Swift and auto layout (but can't comment on the previous Swift answer); here's how I do it without a scroll view:
I layout my form in IB with vertical constraints between the fields to separate them.  I add a vertical constraint from the topmost field to the container view, and create an outlet to that (topSpaceForFormConstraint in the code below).  All that's needed is to update this constraint, which I do in an animation block for a nice soft motion.  The height check is optional of course, in this case I needed to do it just for the smallest screen size.
This can be called using any of the usual textFieldDidBeginEditing or keyboardWillShow methods.
func setFormHeight(top: CGFloat)
{
    let height = UIScreen.mainScreen().bounds.size.height

    // restore text input fields for iPhone 4/4s
    if (height < 568) {
        UIView.animateWithDuration(0.2, delay: 0.0, options: nil, animations: {
            self.topSpaceForFormConstraint.constant = top
            self.view.layoutIfNeeded()
            }, completion: nil)
    }

}

A: This worked for me:
func setupKeyboardNotifications() {
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWasShown:"), name: UIKeyboardDidShowNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillBeHidden:"), name: UIKeyboardWillHideNotification, object: nil)
}

func keyboardWasShown(aNotification:NSNotification) {
    let info = aNotification.userInfo
    let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as NSValue
    let kbSize = infoNSValue.CGRectValue().size
    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationDuration(0.3)
    var rect : CGRect = self.view.frame
    rect.size.height -= kbSize.height

    self.view.frame = rect
    UIView.commitAnimations()
}

func keyboardWillBeHidden(aNotification:NSNotification) {
    let info = aNotification.userInfo
    let infoNSValue = info![UIKeyboardFrameBeginUserInfoKey] as NSValue
    let kbSize = infoNSValue.CGRectValue().size
    UIView.beginAnimations(nil, context: nil)
    UIView.setAnimationDuration(0.3)
    var rect : CGRect = self.view.frame
    rect.size.height += kbSize.height
    self.view.frame = rect
    UIView.commitAnimations()
}

A: In iOS moving keyboard up and taking back for textfields in app is bit confusing and need to implement few methods for same.
also you need to make delegate to textfield and take care of it.
Code for it will repeat in every class where the text fields exist.
I prefer to use this Github control.
IQKeyboard
In which
We do not need to do anything. -- just drag drop control to your project and build. -- It will do everything for your app.
Thanks
May be this will be useful.

A: i had an issue with reseting to default main view while changing the text field or editing it's content (for example phone textfield and adding '-' sign, and view goes back covering textfields)
i finnaly overcome this by using auto layout and changing constraints constant, not frame size or position in notification delegates functions, like this:
P.S. I'm not using scrollview just simple move view up, but it should work similar
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
    if !keyboardIsShown{
        self.infoViewTopConstraint.constant -= keyboardSize.height
        self.infoViewBottomConstraint.constant += keyboardSize.height
        self.view.setNeedsLayout()
        self.view.layoutIfNeeded()
        keyboardIsShown = true
    }
}

func keyboardWillHide(notification: NSNotification) {
if keyboardIsShown {
    self.infoViewTopConstraint.constant += keyboardSize.height
    self.infoViewBottomConstraint.constant -= keyboardSize.height
    self.view.setNeedsLayout()
    self.view.layoutIfNeeded()
    keyboardIsShown = false
}

A: For Swift Developer, using Swift 3, here is the repo https://github.com/jamesrochabrun/KeyboardWillShow
import UIKit

class ViewController: UIViewController {

    //1 Create a view that will hold your TEXTFIELD
    let textField: UITextField = {
        let tf = UITextField()
        tf.translatesAutoresizingMaskIntoConstraints = false
        tf.layer.borderColor = UIColor.darkGray.cgColor
        tf.layer.borderWidth = 3.0
        return tf
    }()
    //2 global variable that will hold the bottom constraint on changes
    var textfieldBottomAnchor: NSLayoutConstraint?

    override func viewDidLoad() {
        super.viewDidLoad()
        //3 add the view to your controller
        view.addSubview(textField)
        textField.heightAnchor.constraint(equalToConstant: 80).isActive = true
        textField.widthAnchor.constraint(equalToConstant: view.frame.width).isActive = true
        textField.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
        textfieldBottomAnchor = textField.bottomAnchor.constraint(equalTo: view.bottomAnchor)
        textfieldBottomAnchor?.isActive = true

        setUpKeyBoardObservers()
    }
    //4 Use NSnotificationCenter to monitor the keyboard updates
    func setUpKeyBoardObservers() {
        NotificationCenter.default.addObserver(self, selector: #selector(handleKeyboardWillShow), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(handleKeyboardWillHide), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
    }

    //5 toggle the bottom layout global variable based on the keyboard's height
    func handleKeyboardWillShow(notification: NSNotification) {

        let keyboardFrame = notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? CGRect
        if let keyboardFrame = keyboardFrame {
            textfieldBottomAnchor?.constant = -keyboardFrame.height
        }
        let keyboardDuration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? Double
        if let keyboardDuration = keyboardDuration {
            UIView.animate(withDuration: keyboardDuration, animations: {
                self.view.layoutIfNeeded()
            })
        }
    }

    func handleKeyboardWillHide(notification: NSNotification) {

        textfieldBottomAnchor?.constant = 0
        let keyboardDuration = notification.userInfo?[UIKeyboardAnimationDurationUserInfoKey] as? Double
        if let keyboardDuration = keyboardDuration {
            UIView.animate(withDuration: keyboardDuration, animations: {
                self.view.layoutIfNeeded()
            })
        }
    }
    //6 remove the observers
    override func viewDidDisappear(_ animated: Bool) {
        super.viewDidDisappear(animated)

        NotificationCenter.default.removeObserver(self)
    }
}

A: You can use this simple Git repository:
https://github.com/hackiftekhar/IQKeyboardManager
This is a library that manages all the moving of fields automatically.
According to their readme, the integration is super easy:

without needing you to enter any code and no additional setup required. To use IQKeyboardManager you simply need to add source files to your project

Although,this is very good control, in some cases it causes conflict, like in the view controllers with scroll view. It sometimes changes the content size. Still, you can go for it, and try it as per your requirement maybe you could do what I missed.

A: This question has already a lot of answers, some said to use scroll view, some said to use a third lib.
But for me the idea solution should be UITableViewController with static cells.
You separate your UI to multiple part and put them in the tableViewCells one by one, than your don't need worry about keyboard anymore, tableViewController will manage it for you automatically.
It may be a little difficult to calculate the padding, margin, cell height, but if your math is ok, it's simple.

A: We can user given code for Swift 4.1
    let keyBoardSize = 80.0

    func keyboardWillShow() {

    if view.frame.origin.y >= 0 {
    viewMovedUp = true
     }
     else if view.frame.origin.y < 0 {
    viewMovedUp = false
   }
  }

func keyboardWillHide() {
 if view.frame.origin.y >= 0 {
    viewMovedUp = true
 }
 else if view.frame.origin.y < 0 {
    viewMovedUp = false
 }

}

func textFieldDidBeginEditing(_ textField: UITextField) {
   if sender.isEqual(mailTf) {
    //move the main view, so that the keyboard does not hide it.
    if view.frame.origin.y >= 0 {
        viewMovedUp = true
    }
  }
}

func setViewMovedUp(_ movedUp: Bool) {
UIView.beginAnimations(nil, context: nil)
UIView.setAnimationDuration(0.3)
    // if you want to slide up the view
let rect: CGRect = view.frame
if movedUp {

    rect.origin.y -= keyBoardSize
    rect.size.height += keyBoardSize
}
else {
    // revert back to the normal state.
    rect.origin.y += keyBoardSize
    rect.size.height -= keyBoardSize
 }
 view.frame = rect
 UIView.commitAnimations()
}

func viewWillAppear(_ animated: Bool)  {
super.viewWillAppear(animated)

NotificationCenter.default.addObserver(self, selector:#selector(self.keyboardWillShow), name: .UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector:#selector(self.keyboardWillHide), name: .UIKeyboardWillHide, object: nil)
}

func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)

NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillShow, object: nil)
NotificationCenter.default.removeObserver(self, name: .UIKeyboardWillHide, object: nil)
}

A: Add my 5 cent :)
I always prefer to use tableView for inputTextField or scrollView. In combination with Notifications you can easily mange such behavior. (Note, if you use static cells in tableView such behaviour will manage automatically for you.)
// MARK: - Notifications
fileprivate func registerNotificaitions() {
    NotificationCenter.default.addObserver(self, selector: #selector(AddRemoteControlViewController.keyboardWillAppear(_:)),
                                           name: NSNotification.Name.UIKeyboardWillShow, object: nil)
    NotificationCenter.default.addObserver(self, selector: #selector(AddRemoteControlViewController.keyboardWillDisappear),
                                           name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}

fileprivate func unregisterNotifications() {
    NotificationCenter.default.removeObserver(self)
}

@objc fileprivate func keyboardWillAppear(_ notification: Notification) {
    if let keyboardHeight = (notification.userInfo?[UIKeyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue.height {
        view.layoutIfNeeded()
        UIView.animate(withDuration: 0.3, animations: {
            let heightInset = keyboardHeight - self.addDeviceButton.frame.height
            self.tableView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: heightInset, right: 0)
            self.view.layoutIfNeeded()
        }, completion: nil)
    }
}

@objc fileprivate func keyboardWillDisappear() {
    view.layoutIfNeeded()
    UIView.animate(withDuration: 0.3, animations: {
        self.tableView.contentInset = UIEdgeInsets.zero
        self.view.layoutIfNeeded()
    }, completion: nil)
}

A: If the text field should be at the bottom of the screen, then the most magical solution is the following override on your viewcontroller:
override var inputAccessoryView: UIView? {
    return <yourTextField>
}

A: Here is my 'UITextView extension only' solution, building upon solution by Paul Hudson @twostraws (regards to him and to all authors of similar answers here).
import UIKit

extension UITextView {

    func adjustableForKeyboard() {
        let notificationCenter = NotificationCenter.default

        notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardWillHideNotification, object: nil)
        notificationCenter.addObserver(self, selector: #selector(adjustForKeyboard), name: UIResponder.keyboardWillChangeFrameNotification, object: nil)
    }

    @objc private func adjustForKeyboard(notification: Notification) {
        guard let keyboardValue = notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue else {
            return
        }

        let keyboardScreenEndFrame = keyboardValue.cgRectValue
        let keyboardViewEndFrame = convert(keyboardScreenEndFrame, from: window)

        if notification.name == UIResponder.keyboardWillHideNotification {
            contentInset = .zero
        } else {
            contentInset = UIEdgeInsets(top: 0, left: 0, bottom: keyboardViewEndFrame.height - safeAreaInsets.bottom, right: 0)
        }

        scrollIndicatorInsets = contentInset
        scrollRangeToVisible(selectedRange)
    }
}

Usage:
override func viewDidLoad() {
    super.viewDidLoad()

    textView.adjustableForKeyboard()
}

A: First of all, I recommend a better design for your page so that there is no need to scroll your view. If you have many text fields, you still don't have to use a ScrollView, it just makes things complicated. You can just add a container UIView on the top of the controller's original view, then put those text fields on that view. When the keyboard shows or disappears, just use an animation to move this container view.

A: Try this it's working perfectly:
if Firstnametxt.text == "" || Passwordtxt.text == "" || emailtxt.text == ""
    {
        if Firstnametxt.text == ""
        {
            Firstnametxt!.shake(10, withDelta: 5, speed: 0.05, shakeDirection: ShakeDirection.Horizontal)
            Firstnametxt.becomeFirstResponder()
        }
        else if Passwordtxt.text == ""
        {
            Passwordtxt!.shake(10, withDelta: 5, speed: 0.05, shakeDirection: ShakeDirection.Horizontal)
            Passwordtxt.becomeFirstResponder()
        }
        else if emailtxt.text == ""

        {

            emailtxt!.shake(10, withDelta: 5, speed: 0.05, shakeDirection: ShakeDirection.Horizontal)
            emailtxt.becomeFirstResponder()
        }

    }
    else
    {
        let isValidEmail:Bool = self.isValidEmail(emailtxt.text!)
        if isValidEmail == true
        {
                        }
        else
        {
            emailtxt!.shake(10, withDelta: 5, speed: 0.05, shakeDirection: ShakeDirection.Horizontal)
            emailtxt.becomeFirstResponder()

        }

    }

A: IF YOU ARE STILL STRUGGLING WITH THIS — READ MY POST
I have come up with a solution today.
I've read numerous posts and "tutorials" about this issue and NONE of them works in every case (most of them are copy-pastes of each other).
Even Apple's officially proposed "solution" doesn't work, and more, it totally doesn't work in landscape mode.
Shame on Apple for not giving the devs means to beat such a common basic issue. Very unprofessional. Such an amazing framework (Cocoa) and such a nasty underrated issue.
Now, my solution: make UIScrollView your root view and then put everything in it.
Then subclass your view controller from this KeyboardAwareController class (you may want to redefine scrollView and keyboardPadding methods):
//
    //  KeyboardAwareController.h
    //  Sociopathy
    //
    //  Created by Admin on 13.01.14.
    //  Copyright (c) 2014 kuchumovn. All rights reserved.
    //
#import <UIKit/UIKit.h>

@interface KeyboardAwareController : UIViewController <UITextFieldDelegate>

@end

//
    //  KeyboardAwareController.m
    //  Sociopathy
    //
    //  Created by Admin on 13.01.14.
    //  Copyright (c) 2014 kuchumovn. All rights reserved.
    //
#import "KeyboardAwareController.h"

@interface KeyboardAwareController ()

@end

@implementation KeyboardAwareController
{
    CGPoint scrollPositionBeforeKeyboardAdjustments;

    __weak UIScrollView* scrollView;

    UITextField* activeField;
}

- (id) initWithCoder: (NSCoder*) decoder
{
    if (self = [super initWithCoder:decoder])
    {
        scrollPositionBeforeKeyboardAdjustments = CGPointZero;
    }
    return self;
}

- (void) viewDidLoad
{
    [super viewDidLoad];
}

- (UIScrollView*) scrollView
{
    return (UIScrollView*) self.view;
}

- (CGFloat) keyboardPadding
{
    return 5;
}

- (void) registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardDidShow:)
                                                 name:UIKeyboardDidShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];
}

- (void) deregisterFromKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardWillShowNotification
                                                  object:nil];

    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardDidShowNotification
                                                  object:nil];

    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardWillHideNotification
                                                  object:nil];
}

- (void) viewWillAppear: (BOOL) animated
{
    [super viewWillAppear:animated];

    [self registerForKeyboardNotifications];
}

- (void) viewWillDisappear: (BOOL) animated
{
    [self deregisterFromKeyboardNotifications];

    [super viewWillDisappear:animated];
}

- (void) keyboardWillShow: (NSNotification*) notification
{
    //NSLog(@"keyboardWillShow");

    // force the animation from keyboardWillBeHidden: to end
    scrollView.contentOffset = scrollPositionBeforeKeyboardAdjustments;

    scrollPositionBeforeKeyboardAdjustments = CGPointZero;
}

// warning: i have no idea why this thing works and what does every line of this code mean
// (but it works and there is no other solution on the internets whatsoever)
// P.S. Shame on Apple for missing such a basic functionality from SDK (and many other basic features we have to hack and mess around with for days and nights)

- (void) keyboardDidShow: (NSNotification*) notification
{
    //NSLog(@"keyboardDidShow");

    UIWindow* window = [[[UIApplication sharedApplication] windows]objectAtIndex:0];
    UIView* mainSubviewOfWindow = window.rootViewController.view;

    CGRect keyboardFrameIncorrect = [[[notification userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGRect keyboardFrame = [mainSubviewOfWindow convertRect:keyboardFrameIncorrect fromView:window];
    CGSize keyboardSize = keyboardFrame.size;

    CGRect visibleFrame = CGRectMake(0, 0, 0, 0);
    visibleFrame.origin = self.scrollView.contentOffset;
    visibleFrame.size = self.scrollView.bounds.size;

    CGFloat paddedKeyboardHeight = keyboardSize.height + self.keyboardPadding;

    //NSLog(@"visibleFrame %@", NSStringFromCGRect(visibleFrame));

    visibleFrame.size.height -= paddedKeyboardHeight;

    //NSLog(@"visibleFrame after keyboard height %@", NSStringFromCGRect(visibleFrame));

    if (CGRectContainsPoint(visibleFrame, activeField.frame.origin))
        return;

    scrollPositionBeforeKeyboardAdjustments = scrollView.contentOffset;

    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0.0, 0.0, activeField.frame.origin.y - visibleFrame.size.height + activeField.frame.size.height, 0);

    contentInsets = UIEdgeInsetsMake(0.0, 0.0, paddedKeyboardHeight, 0);

    self.scrollView.contentInset = contentInsets;
    self.scrollView.scrollIndicatorInsets = contentInsets;

    CGSize scrollContentSize = self.scrollView.bounds.size;
    scrollContentSize.height += paddedKeyboardHeight;
    self.scrollView.contentSize = scrollContentSize;

    //NSLog(@"scrollView %@", NSStringFromCGRect(scrollView.frame));
    //NSLog(@"activeField %@", NSStringFromCGRect(activeField.frame));

    //[scrollView scrollRectToVisible:activeField.frame animated:YES];

    CGPoint scrollPoint = CGPointMake(0.0, activeField.frame.origin.y - visibleFrame.size.height + activeField.frame.size.height);

    //NSLog(@"scrollPoint %@", NSStringFromCGPoint(scrollPoint));

    [self.scrollView setContentOffset:scrollPoint animated:YES];
}

- (void) keyboardWillBeHidden: (NSNotification*) notification
{
    //NSLog(@"keyboardWillBeHidden");

    UIEdgeInsets contentInsets = UIEdgeInsetsZero;

    // this doesn't work when changing orientation while the keyboard is visible
    // because when keyboardDidShow: will be called right after this method the contentOffset will still be equal to the old value
    //[scrollView setContentOffset:scrollPositionBeforeKeyboardAdjustments animated:YES];

    [UIView animateWithDuration:.25 animations:^
    {
        self.scrollView.contentInset = contentInsets;
        self.scrollView.scrollIndicatorInsets = contentInsets;

        // replacement for setContentOffset:animated:
        self.scrollView.contentOffset = scrollPositionBeforeKeyboardAdjustments;
    }];
}

- (void) textFieldDidBeginEditing: (UITextField*) textField
{
    activeField = textField;
}

- (void) textFieldDidEndEditing: (UITextField*) textField
{
    activeField = nil;
}
@end

If you have any questions, my project is hosted here on github:
https://github.com/kuchumovn/sociopathy.ios
I also took a screenshot for better explanation:

A: Refer follwing
import UIKit
@available(tvOS, unavailable)
public class KeyboardLayoutConstraint: NSLayoutConstraint {

    private var offset : CGFloat = 0
    private var keyboardVisibleHeight : CGFloat = 0

    @available(tvOS, unavailable)
    override public func awakeFromNib() {
        super.awakeFromNib()

        offset = constant

        NotificationCenter.default.addObserver(self, selector: #selector(KeyboardLayoutConstraint.keyboardWillShowNotification(_:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(KeyboardLayoutConstraint.keyboardWillHideNotification(_:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
    }

    deinit {
        NotificationCenter.default.removeObserver(self)
    }

    // MARK: Notification

    @objc func keyboardWillShowNotification(_ notification: Notification) {
        if let userInfo = notification.userInfo {
            if let frameValue = userInfo[UIKeyboardFrameEndUserInfoKey] as? NSValue {
                let frame = frameValue.cgRectValue
                keyboardVisibleHeight = frame.size.height
            }

            self.updateConstant()
            switch (userInfo[UIKeyboardAnimationDurationUserInfoKey] as? NSNumber, userInfo[UIKeyboardAnimationCurveUserInfoKey] as? NSNumber) {
            case let (.some(duration), .some(curve)):

                let options = UIViewAnimationOptions(rawValue: curve.uintValue)

                UIView.animate(
                    withDuration: TimeInterval(duration.doubleValue),
                    delay: 0,
                    options: options,
                    animations: {
                        UIApplication.shared.keyWindow?.layoutIfNeeded()
                        return
                    }, completion: { finished in
                })
            default:

                break
            }

        }

    }

    @objc func keyboardWillHideNotification(_ notification: NSNotification) {
        keyboardVisibleHeight = 0
        self.updateConstant()

        if let userInfo = notification.userInfo {

            switch (userInfo[UIKeyboardAnimationDurationUserInfoKey] as? NSNumber, userInfo[UIKeyboardAnimationCurveUserInfoKey] as? NSNumber) {
            case let (.some(duration), .some(curve)):

                let options = UIViewAnimationOptions(rawValue: curve.uintValue)

                UIView.animate(
                    withDuration: TimeInterval(duration.doubleValue),
                    delay: 0,
                    options: options,
                    animations: {
                        UIApplication.shared.keyWindow?.layoutIfNeeded()
                        return
                    }, completion: { finished in
                })
            default:
                break
            }
        }
    }

    func updateConstant() {
        self.constant = offset + keyboardVisibleHeight
    }

}

A: If you want your UIView shift properly and your active textfield should accurately position to user need so that he/she can see whatever they are input .
For that you must use Scrollview .
This suppose to be your UIView hierarchy .
ContainerView -> ScrollView -> ContentView -> Your View .
If you have made UIView design as per above discuss hierarchy, now in your controller class you need add notifications observer in viewwillappear and remove observer in viewwilldissappear .
But this approach needs to add on every controller where ever UIView need to shifts .
I have been using  'TPKeyboardAvoiding' pod . It is reliable and easily handle shift of UIView for every possible case wether if you are Scrollview , TableView  or CollectionView . You just need to pass class to your 'scrolling view' .
Like below

You can change this class if you are tableview  to 'TPKeyboardAvoidingTableView'.
You can find complete running project Project Link
This robust approach I've been followed for development . Hope this helps!

A: SwiftUI Using ViewModifier
You can use ViewModifier of SwiftUI. It is much simpler.
import SwiftUI
import Combine

struct KeyboardAwareModifier: ViewModifier {
    @State private var keyboardHeight: CGFloat = 0

    private var keyboardHeightPublisher: AnyPublisher<CGFloat, Never> {
        Publishers.Merge(
            NotificationCenter.default
                .publisher(for: UIResponder.keyboardWillShowNotification)
                .compactMap { $0.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue }
                .map { $0.cgRectValue.height },
            NotificationCenter.default
                .publisher(for: UIResponder.keyboardWillHideNotification)
                .map { _ in CGFloat(0) }
       ).eraseToAnyPublisher()
    }

    func body(content: Content) -> some View {
        content
            .padding(.bottom, keyboardHeight)
            .onReceive(keyboardHeightPublisher) { self.keyboardHeight = $0 }
    }
}

extension View {
    func KeyboardAwarePadding() -> some View {
        ModifiedContent(content: self, modifier: KeyboardAwareModifier())
    }
}

And in your view
struct SomeView: View {
    @State private var someText: String = ""

    var body: some View {
        VStack {
            Spacer()
            TextField("some text", text: $someText)
        }.KeyboardAwarePadding()
    }
}

KeyboardAwarePadding() will automatically add a padding to your view. It's more elegant.