public boolean isInTargetZone(float x,float y){
  return (Math.abs(x - mX) <= mTargetRadiusPx && Math.abs(y - mY + mPinPadding) <= mTargetRadiusPx);
}

public boolean isInTargetZone ( float x , float y ) { return ( Math . abs ( x - mX ) <= mTargetRadiusPx && Math . abs ( y - mY + mPinPadding ) <= mTargetRadiusPx ) ; }
determines if the input coordinate is close enough to this thumb to consider it a press .
