Get speed of a onTouch ACTION_MOVE event in Android

Question

This should be a pretty simple thing to do. The user puts his finger on the screen and drags it around the screen. There are two events firing on onTouch:

• MotionEvent.ACTION_DOWN
• MotionEvent.ACTION_MOVE

Now, how can I calculate the speed of the ACTION_MOVE gesture ? The user drags the finger slower or faster during a gesture, so I think I need to calculate the speed between two intermediate touched points: the lastTouchedPointX,lastTouchedPointY and the event.getX(),event.getY().

Has anyone done this before ?

Answer 1

@Override
        public boolean onTouchEvent(MotionEvent event, MapView mapView) {


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

                oldX = event.getX();
                oldY = event.getY();
                    //start timer

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

                //long timerTime = getTime between two event down to Up
                newX = event.getX();
                newY = event.getY();

                float distance = Math.sqrt((newX-oldX) * (newX-oldX) + (newY-oldY) * (newY-oldY));
                float speed = distance / timerTime;

            }
}