DoubleTap in android

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Android: How to detect double-tap? 15 answers

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If you do the setup right, the OnDoubleTapListener , within the GestureListener is very useful. You dont need to handle each single tap and count time in between. Instead let Android handle for you what a tap, a double-tap, a scroll or fling might be. With the helper class SimpleGestureListener that implements the GestureListener and OnDoubleTapListener you dont need much to do.

findViewById(R.id.touchableText).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;
    }
});

Note: I tested around quite a while to find out, what the right mixture of return true and return false is. This was the really tricky part here.

Another note: When you test this, do it on a real device , instead of the emulator. I had real trouble getting the mouse fast enough to create an onFling event. Real fingers on real devices seem to be much faster.

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A better alternative is to create a lightweight Abstract Class

public abstract class DoubleClickListener implements OnClickListener {

    private static final long DOUBLE_CLICK_TIME_DELTA = 300;//milliseconds

    long lastClickTime = 0;

    @Override
    public void onClick(View v) {
        long clickTime = System.currentTimeMillis();
        if (clickTime - lastClickTime < DOUBLE_CLICK_TIME_DELTA){
            onDoubleClick(v);
            lastClickTime = 0;
        } else {
            onSingleClick(v);
        }
        lastClickTime = clickTime;
    }

    public abstract void onSingleClick(View v);
    public abstract void onDoubleClick(View v);
}

And use it like

 view.setOnClickListener(new DoubleClickListener() {

        @Override
        public void onSingleClick(View v) {

        }

        @Override
        public void onDoubleClick(View v) {

        }
    });

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非常简单的逻辑使用以下代码

    boolean firstTouch = false;
        @Override
        public boolean onTouchEvent(MotionEvent event) {
            if(event.getAction() == event.ACTION_DOWN){
                if(firstTouch && (Helper.getCurrentTimeInMilliSeconds() - time) <= 300) {
                    //do stuff here for double tap
                    Log.e("** DOUBLE TAP**"," second tap ");
                    firstTouch = false;

                } else {
                    firstTouch = true;
                    time = Helper.getCurrentTimeInMilliSeconds();
                    Log.e("** SINGLE  TAP**"," First Tap time  "+time);
                    return false;
                }
            }
            return true;
    }

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