Round button in android.. avoid presses “outside” the button?

Question

I have created/tried to create, a round button for android by using the ImageButton \"widget\". But since that type of button is treated as a square and my png-image also is

Answer 1

Try Pythagorean theorem and onTouch, simple and easy way to do it.

public boolean inCircle(MotionEvent e, int radius, int x, int y) {
    int dx = e.x - x;
    int dy = e.y - y;
    double d = Math.sqrt((dx * dx) + (dy * dy));
    if(d < radius)
        return true;
    return false;
}

the x, y is the posision of the circle, the radius is the radius, and the e is the TouchEvent you have.

@Override
public boolean onTouch(View arg0, MotionEvent arg1) {
    if(arg1.getAction() == MotionEvent.ACTION_DOWN){
           if(inCircle(arg1, radius, xCircle, yCircle){
                  //do whatever you wanna do here
                  }
            }
    return false;
}