How to do something repeatedly while a button is pressed?

Question

I'm developing a TV-Remote Simulator app in Android using a specific middleware (not of importance).

In the case of Volume Buttons (Volume+ and Volume-), what I'm trying to do is to send the "Volume Up" signal repeatedly while its button is pressed.

That's what I tried at last (code for one of the buttons, the other must be identical except for the names):

1. Declared a boolean variable

   boolean pressedUp = false;
   

2. Declared a inner class with the following AsyncTask:

   class SendVolumeUpTask extends AsyncTask<Void, Void, Void> {
   
       @Override
       protected Void doInBackground(Void... arg0) {
           while(pressedUp) {
               SendVolumeUpSignal();
       }
       return null;
   }
   

   }

3. Add the listener to the button:

   final Button buttonVolumeUp = (Button) findViewById(R.id.volup);
   buttonVolumeUp.setOnTouchListener(new View.OnTouchListener() {
   
       @Override
       public boolean onTouch(View v, MotionEvent event) {
           switch (event.getAction()) {
   
           case MotionEvent.ACTION_DOWN:
   
               if(pressedUp == false){
                   pressedUp = true;
                   new SendVolumeUpTask().execute();
               }
   
           case MotionEvent.ACTION_UP:
   
               pressedUp = false;
   
       }
           return true;
       }
   });
   

I've also tried with simple threads as in Increment-Decrement counter while button is pressed but neither worked. The application works finely for the rest of the buttons (channels, etc.), but volume changing is completely ignored.

Answer 1

You forgot to add a break; at the end of the MotionEvent.ACTION_DOWN: case. That means the line pressedUp = false; gets executed even on that action. The correct thing to do would be:

@Override
public boolean onTouch(View v, MotionEvent event) {
    switch (event.getAction()) {

    case MotionEvent.ACTION_DOWN:

        if(pressedUp == false){
            pressedUp = true;
            new SendVolumeUpTask().execute();
        }
    break;
    case MotionEvent.ACTION_UP:

        pressedUp = false;

}
    return true;
}

Answer 2

Have you considered

• Starting your repititive task on the onKeyDown event
• Stopping the task on the onKeyUp event ?