title: App crashes after adding gesture UITapGestureRecognizer to UILabel
body: <p>I'm fairly new to Objective C. I am trying to add a tap gesture recognizer to the UILabel. But the app crashes when trying to call the selector method. Here's what I am doing.</p>
  
  <pre><code>     - (instancetype)initWithCard:(Card *)obj {
  //few lines of code here...
       UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self.selectionHeaderLabel action:@selector(onLabelTapped:)];
                      _selectionHeaderLabel.userInteractionEnabled = YES;
                      [self.selectionHeaderLabel addGestureRecognizer:tap];
      }
  
      -(void) onLabelTapped:(UITapGestureRecognizer *) recognizer {
          if ([recognizer state] == UIGestureRecognizerStateEnded) {
              //do some stuff
          }
      }
  </code></pre>
  
  <p>I followed this answer, but that is not helping me.
  <a href="https://stackoverflow.com/a/9058735/4863339">https://stackoverflow.com/a/9058735/4863339</a></p>
  
  <p><strong>EDIT</strong>: Here is the crash report</p>
  
  <blockquote>
    <p>Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UILabel onLabelTapped:]: unrecognized selector sent to instance 0x7f8c4f5252e0'
    *** First throw call stack:
    (
        0   CoreFoundation                      0x000000011027334b <strong>exceptionPreprocess + 171
        1   libobjc.A.dylib                     0x000000010f7d821e objc_exception_throw + 48
        2   CoreFoundation                      0x00000001102e2f34 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132
        3   CoreFoundation                      0x00000001101f8c15 ___forwarding_</strong> + 1013
        4   CoreFoundation                      0x00000001101f8798 _CF_forwarding_prep_0 + 120
        5   UIKit                               0x000000010da5f289 -[UIGestureRecognizerTarget _sendActionWithGestureRecognizer:] + 57
        6   UIKit                               0x000000010da67028 _UIGestureRecognizerSendTargetActions + 109
        7   UIKit                               0x000000010da64af7 _UIGestureRecognizerSendActions + 227
        8   UIKit                               0x000000010da63d83 -[UIGestureRecognizer _updateGestureWithEvent:buttonEvent:] + 891
        9   UIKit                               0x000000010da4fe56 _UIGestureEnvironmentUpdate + 1395
        10  UIKit                               0x000000010da4f89b -[UIGestureEnvironment _deliverEvent:toGestureRecognizers:usingBlock:] + 521
        11  UIKit                               0x000000010da4ea7e -[UIGestureEnvironment _updateGesturesForEvent:window:] + 286
        12  UIKit                               0x000000010d58d7ad -[UIWindow sendEvent:] + 3989
        13  UIKit                               0x000000010d53aa33 -[UIApplication sendEvent:] + 371
        14  UIKit                               0x000000010dd2cb6d <strong>dispatchPreprocessedEventFromEventQueue + 3248
        15  UIKit                               0x000000010dd25817 __handleEventQueue + 4879
        16  CoreFoundation                      0x0000000110218311 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION</strong> + 17
        17  CoreFoundation                      0x00000001101fd59c __CFRunLoopDoSources0 + 556
        18  CoreFoundation                      0x00000001101fca86 __CFRunLoopRun + 918
        19  CoreFoundation                      0x00000001101fc494 CFRunLoopRunSpecific + 420
        20  GraphicsServices                    0x0000000114460a6f GSEventRunModal + 161
        21  UIKit                               0x000000010d51cf34 UIApplicationMain + 159
        22  CollPoll                            0x000000010bdcf8df main + 111
        23  libdyld.dylib                       0x000000011267a68d start + 1
    )
    libc++abi.dylib: terminating with uncaught exception of type NSException</p>
  </blockquote>