code: public void show(ViewGroup parent, int x, int y, int gravity){
  		if(getParent() == null){
  			ViewGroup.LayoutParams params = parent.generateLayoutParams(null);
  			params.width = mBackground.getIntrinsicWidth();
  			params.height = mBackground.getIntrinsicHeight();
  			updateParams(x, y, gravity, params);
  
  			parent.addView(this, params);
  		}
  		else
  			updateLocation(x, y, gravity);
  	}
docs: Show this button at the specific location. If this button isn't attached to any parent view yet,
  it will be add to activity's root view. If not, it will just update the location.
  @param parent The parent view. Should be {@link FrameLayout} or {@link RelativeLayout}
  @param x The x value of anchor point.
  @param y The y value of anchor point.
  @param gravity The gravity apply with this button.
  
  @see Gravity