ImageView doesn't dispatch TouchEvent

I want to change the image (that I get from a web url) in my ImageView when I touch the left or right of the screen. I tried using a TouchListener but I get an error about dispatchTouchEvent.

Using a gallery view is not the solution because I want the images displayed in full screen.

This is the code I use.

 public class Prova4Activity extends Activity implements OnTouchListener {
 /** Called when the activity is first created. */
 ImageView image;
 Bitmap trash = loadImageFromUrl("http://www.televideo.rai.it/televideo/pub/tt4web/Nazionale/16_9_page-100.6.png");
 ImageView imgpag;
 @Override
 public boolean onTouch(View v, MotionEvent event) {
     if(event.getAction() == MotionEvent.EDGE_RIGHT){
         trash.recycle();
          trash = null;
          trash = loadImageFromUrl("http://www.televideo.rai.it/televideo/pub/tt4web/Nazionale/16_9_page-100.6.png");
          image.setImageBitmap(trash);
 
          }else if(event.getAction() == MotionEvent.EDGE_LEFT){
              trash.recycle();
              trash = null;
              trash = loadImageFromUrl("http://www.televideo.rai.it/televideo/pub/tt4web/Nazionale/16_9_page-100.5.png");
              imgpag.setImageBitmap(trash);
 
          }
     imgpag.setScaleType(ScaleType.FIT_XY);
 
     return false;
 }
 @Override
 public void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setContentView(R.layout.main);
 
     imgpag = (ImageView)findViewById (R.id.imgpag); 
     imgpag.setImageBitmap(trash);
     imgpag.setOnTouchListener(this);
 
 }
 }
 

In logcat I see the following message many times:

Key dispatching timed out sending to com.namemyapp Current state {{null Window{439f0e10 com.namemyapp Continuing to wait for key to be dispatched
 

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