Gesture Detection

Remarks

Official Documentation: Detecting Common Gestures

Basic Gesture Detection

public class GestureActivity extends Activity implements
        GestureDetector.OnDoubleTapListener,
        GestureDetector.OnGestureListener {

    private GestureDetector mGestureDetector;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mGestureDetector = new GestureDetector(this, this);
        mGestureDetector.setOnDoubleTapListener(this);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event){
        mGestureDetector.onTouchEvent(event);
        return super.onTouchEvent(event);
    }

    @Override
    public boolean onDown(MotionEvent event) {
        Log.d("GestureDetector","onDown");
        return true;
    }

    @Override
    public boolean onFling(MotionEvent event1, MotionEvent event2, float velocityX, float velocityY) {
        Log.d("GestureDetector","onFling");
        return true;
    }

    @Override
    public void onLongPress(MotionEvent event) {
        Log.d("GestureDetector","onLongPress");
    }

    @Override
    public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
        Log.d("GestureDetector","onScroll");
        return true;
    }

    @Override
    public void onShowPress(MotionEvent event) {
        Log.d("GestureDetector","onShowPress");
    }

    @Override
    public boolean onSingleTapUp(MotionEvent event) {
        Log.d("GestureDetector","onSingleTapUp");
        return true;
    }

    @Override
    public boolean onDoubleTap(MotionEvent event) {
        Log.d("GestureDetector","onDoubleTap");
        return true;
    }

    @Override
    public boolean onDoubleTapEvent(MotionEvent event) {
        Log.d("GestureDetector","onDoubleTapEvent");
        return true;
    }

    @Override
    public boolean onSingleTapConfirmed(MotionEvent event) {
        Log.d("GestureDetector","onSingleTapConfirmed");
        return true;
    }
    
}

Swipe Detection

public class OnSwipeListener implements View.OnTouchListener {

    private final GestureDetector gestureDetector;

    public OnSwipeListener(Context context) {
        gestureDetector = new GestureDetector(context, new GestureListener());
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        return gestureDetector.onTouchEvent(event);
    }

    private final class GestureListener extends GestureDetector.SimpleOnGestureListener {

        private static final int SWIPE_VELOCITY_THRESHOLD = 100;
        private static final int SWIPE_THRESHOLD = 100;

        @Override
        public boolean onDown(MotionEvent e) {
            return true;
        }

        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            float diffY = e2.getY() - e1.getY();
            float diffX = e2.getX() - e1.getX();
            if (Math.abs(diffX) > Math.abs(diffY)) {
                if (Math.abs(diffX) > SWIPE_THRESHOLD && Math.abs(velocityX) > SWIPE_VELOCITY_THRESHOLD) {
                    if (diffX > 0) {
                        onSwipeRight();
                    } else {
                        onSwipeLeft();
                    }
                }
            } else if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY_THRESHOLD) {
                if (diffY > 0) {
                    onSwipeBottom();
                } else {
                    onSwipeTop();
                }
            }
            return true;
        }
    }

    public void onSwipeRight() {
    }

    public void onSwipeLeft() {
    }

    public void onSwipeTop() {
    }

    public void onSwipeBottom() {
    }

}

Applied to a view...

view.setOnTouchListener(new OnSwipeListener(context) {
    public void onSwipeTop() {
        Log.d("OnSwipeListener", "onSwipeTop");
    }
    public void onSwipeRight() {
        Log.d("OnSwipeListener", "onSwipeRight");
    }
    public void onSwipeLeft() {
        Log.d("OnSwipeListener", "onSwipeLeft");
    }
    public void onSwipeBottom() {
        Log.d("OnSwipeListener", "onSwipeBottom");
    }

});
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