Is there an example of how to use a TouchDelegate in Android to increase the size of a view's click target?

Question

My understanding is that when you have a view that\'s too small to easily touch, you\'re supposed to use a TouchDelegate to increase the clickable region for that view.

Answer 1

According to @Mason Lee comment, this solved my problem. My project had relative layout and one button. So parent is -> layout and child is -> a button.

Here is a google link example google code

In case of deleting his very valuable answer I put here his answer.

I was recently asked about how to use a TouchDelegate. I was a bit rusty myself on this and I couldn't find any good documentation on it. Here's the code I wrote after a little trial and error. touch_delegate_view is a simple RelativeLayout with the id touch_delegate_root. I defined with a single, child of the layout, the button delegated_button. In this example I expand the clickable area of the button to 200 pixels above the top of my button.

public class TouchDelegateSample extends Activity {

  Button mButton;   
  @Override   
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.touch_delegate_view);
    mButton = (Button)findViewById(R.id.delegated_button);
    View parent = findViewById(R.id.touch_delegate_root);

    // post a runnable to the parent view's message queue so its run after
    // the view is drawn
    parent.post(new Runnable() {
      @Override
      public void run() {
        Rect delegateArea = new Rect();
        Button delegate = TouchDelegateSample.this.mButton;
        delegate.getHitRect(delegateArea);
        delegateArea.top -= 200;
        TouchDelegate expandedArea = new TouchDelegate(delegateArea, delegate);
        // give the delegate to an ancestor of the view we're delegating the
        // area to
        if (View.class.isInstance(delegate.getParent())) {
          ((View)delegate.getParent()).setTouchDelegate(expandedArea);
        }
      }
    });   
  } 
}

Cheers, Justin Android Team @ Google

Few words from me: if you want expand left side you give value with minus, and if you want expand right side of object, you give value with plus. This works the same with top and bottom.