Question: I know only basic HTML 

I want to put a text box on my website in which if a user enters his order number, it will open the link to that order summary.

The links to those order summary are saved on my web server in the format of ORDERNUMBER-DATE (example: <http://www.mywebsite.com/orders/OD12354-22.02.14.html>)

All I want is 2 text boxes where the user enters order number and a date.
on clicking submit, it should take the user to the link automatically.

Answer: 
You can extend the default `NumberPicker` in your Custom class `CustomNumberPicker` for this:

```
public class CustomNumberPicker extends NumberPicker {

    public NumberPicker(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public void addView(View child) {
        super.addView(child);
        if(child instanceof EditText) {
            ((EditText) child).setTextSize(25);
        }
    }
}

```

Now replace your current `NumberPicker` in xml with `CustomNumberPicker`:

```
<com.pkg.name.CustomNumberPicker
    android:id="@+id/number_picker"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />

```
Although technically not changing the font size, the size of the text can be changed by changing the scale of the entire NumberPicker View.

```
<NumberPicker
    android:id="@+id/number_picker"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:scaleX=".7"
    android:scaleY=".7"/>

```