How to catch double tap events in Android using OnTouchListener

Question

I am trying to catch double-tap events using OnTouchListener. I figure I would set a long for motionEvent.ACTION_DOWN, and a different long for a second motionEvent.ACTION_D

Answer 1

Another approach that supports both single click and double clicks using Kotlin Coroutine:

var lastDown = 0L
var clickCount = 0

view.setOnTouchListener {v, event ->
    when (event.action) {
        MotionEvent.ACTION_DOWN -> {
            val downTime = System.currentTimeMillis()
            clickCount++
            if (lastDown > 0 && downTime - lastDown < 300 && clickCount == 2) {
                //double clicks happens here
                clickCount = 0
            }
            lastDown = downTime
        }
        MotionEvent.ACTION_UP -> {
            CoroutineScope(Dispatchers.IO).launch {
                //in case clickCount goes beyond than 1, here set it to 1
                val upTime = System.currentTimeMillis()
                if (upTime - lastDown <= 300 && clickCount > 0) {
                    clickCount = 1
                }
                delay(300)
                if (System.currentTimeMillis() - lastDown > 300 && clickCount == 1) {
                    withContext(Dispatchers.Main) {
                        //single click happens here
                    }
                    clickCount = 0
                }
            }
        }
    }
    true
}

Answer 2

With the helper class SimpleGestureListener that implements the GestureListener and OnDoubleTapListener you dont need much to do.

yourView.setOnTouchListener(new OnTouchListener() {
private GestureDetector gestureDetector = new GestureDetector(Test.this, new GestureDetector.SimpleOnGestureListener() {
    @Override
    public boolean onDoubleTap(MotionEvent e) {
        Log.d("TEST", "onDoubleTap");
        return super.onDoubleTap(e);
    }
    ... // implement here other callback methods like onFling, onScroll as necessary
});

@Override
public boolean onTouch(View v, MotionEvent event) {
    Log.d("TEST", "Raw event: " + event.getAction() + ", (" + event.getRawX() + ", " + event.getRawY() + ")");
    gestureDetector.onTouchEvent(event);
    return true;
}});

Answer 3

That's much easyer:

//variable for storing the time of first click
long startTime;
//constant for defining the time duration between the click that can be considered as double-tap
static final int MAX_DURATION = 200;

    if (event.getAction() == MotionEvent.ACTION_UP) {

        startTime = System.currentTimeMillis();             
    }
    else if (event.getAction() == MotionEvent.ACTION_DOWN) {

        if(System.currentTimeMillis() - startTime <= MAX_DURATION)
        {
            //DOUBLE TAP
        }       
    }

Answer 4

I addressed this problem earlier. It involves using a Handler to wait a certain amount of time to wait for the second click: How can I create a Single Click Event and Double Click Event when the Menu Button is pressed?

Answer 5

In your class definition:

public class main_activity extends Activity
{
    //variable for counting two successive up-down events
   int clickCount = 0;
    //variable for storing the time of first click
   long startTime;
    //variable for calculating the total time
   long duration;
    //constant for defining the time duration between the click that can be considered as double-tap
   static final int MAX_DURATION = 500;
}

Then in your class body:

OnTouchListener MyOnTouchListener = new OnTouchListener()
{
    @Override
    public boolean onTouch (View v, MotionEvent event)
    {
        switch(event.getAction() & MotionEvent.ACTION_MASK)
        {
        case MotionEvent.ACTION_DOWN:
            startTime = System.currentTimeMillis();
            clickCount++;
            break;
        case MotionEvent.ACTION_UP:
            long time = System.currentTimeMillis() - startTime;
            duration=  duration + time;
            if(clickCount == 2)
            {
                if(duration<= MAX_DURATION)
                {
                    Toast.makeText(captureActivity.this, "double tap",Toast.LENGTH_LONG).show();
                }
                clickCount = 0;
                duration = 0;
                break;             
            }
        }
    return true;    
    }
}

This was adapted from an answer in: DoubleTap in android by https://stackoverflow.com/users/1395802/karn

Answer 6

Here is my solution.

It was important for me to have a fast and clear separation of 'single tap' and 'double tap'. I tried GestureDetector first but had very bad results. Maybe a result of my nested use of scrollviews - who knows...

I focus on MotionEvent.ACTION_UP and the ID of the tapped element. To keep the first tap alive I use a Handler sending a delayed message (350ms) so the user has some time to place its second tap on the ImageView. If the user placed a second tap on an element with the identical id I take this as double tap, remove the delayed message and rund my custom code for 'double tap'. If the user placed a tap on an element with a different ID I take this as new tap and create another Handler for it.

Class global variables

private int tappedItemId = -1;
Handler myTapHandler;
final Context ctx = this;

Code example

ImageView iv = new ImageView(getApplicationContext());
//[...]
iv.setId(i*1000+n);
iv.setOnTouchListener(new View.OnTouchListener() {

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

   switch (event.getAction()) {

      case MotionEvent.ACTION_UP: {

         //active 'tap handler' for current id?
         if(myTapHandler != null && myTapHandler.hasMessages(v.getId())) {

            // clean up (to avoid single tap msg to be send and handled)
            myTapHandler.removeMessages(tappedItemId);
            tappedItemId = -1;

            //run 'double tap' custom code
            Toast.makeText(ScrollView.this, "double tap on "+v.getId(), Toast.LENGTH_SHORT).show();

            return true;
         } else {
            tappedItemId = v.getId();
            myTapHandler = new Handler(){
               public void handleMessage(Message msg){
                  Toast.makeText(ctx, "single tap on "+ tappedItemId + " msg 'what': " + msg.what, Toast.LENGTH_SHORT).show();
               }
            };

            Message msg = Message.obtain();
            msg.what = tappedItemId;
            msg.obj = new Runnable() {
               public void run() {
                  //clean up
                  tappedItemId = -1;
               }
            };
            myTouchHandler.sendMessageDelayed(msg, 350); //350ms delay (= time to tap twice on the same element)
         }
         break;
      }
   }

   return true;
 }
});