Android: Measure/detect covered area by a finger touch on screen (NOT only touch coordinates)

Question

I would like to get access to the area covered by a finger for each touch event on an Android.

Every touch event will result in a coordinate pair X and Y independent

Answer 1

The method motionEvent.getSize() should give you what you want (but the level of accuracy may vary depending on the device's screen).

Answer 2

You need to implement OnGestureListener.

First of all, you need to register GestureDetector in onTouchEvent

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

In onShowPress you will get starting points

@Override
public void onShowPress(MotionEvent e) {
    startX = e.getX();
    startY = e.getY();
}

In onScroll you will get the end points.

@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
        float distanceY) {
            endX = e2.getX();
            endY = e2.getY();
}