public void enter(){
  cancel();
  final int radiusDuration=(int)(1000 * Math.sqrt(mOuterRadius / WAVE_TOUCH_DOWN_ACCELERATION * mDensity) + 0.5);
  final ObjectAnimator radius=ObjectAnimator.ofFloat(this,"radiusGravity",1);
  radius.setAutoCancel(true);
  radius.setDuration(radiusDuration);
  radius.setInterpolator(LINEAR_INTERPOLATOR);
  radius.setStartDelay(RIPPLE_ENTER_DELAY);
  final ObjectAnimator cX=ObjectAnimator.ofFloat(this,"xGravity",1);
  cX.setAutoCancel(true);
  cX.setDuration(radiusDuration);
  cX.setInterpolator(LINEAR_INTERPOLATOR);
  cX.setStartDelay(RIPPLE_ENTER_DELAY);
  final ObjectAnimator cY=ObjectAnimator.ofFloat(this,"yGravity",1);
  cY.setAutoCancel(true);
  cY.setDuration(radiusDuration);
  cY.setInterpolator(LINEAR_INTERPOLATOR);
  cY.setStartDelay(RIPPLE_ENTER_DELAY);
  mAnimRadius=radius;
  mAnimX=cX;
  mAnimY=cY;
  radius.start();
  cX.start();
  cY.start();
}

public void enter ( ) { cancel ( ) ; final int radiusDuration = ( int ) ( 1000 * Math . sqrt ( mOuterRadius / WAVE_TOUCH_DOWN_ACCELERATION * mDensity ) + 0.5 ) ; final ObjectAnimator radius = ObjectAnimator . ofFloat ( this , "radiusGravity" , 1 ) ; radius . setAutoCancel ( true ) ; radius . setDuration ( radiusDuration ) ; radius . setInterpolator ( LINEAR_INTERPOLATOR ) ; radius . setStartDelay ( RIPPLE_ENTER_DELAY ) ; final ObjectAnimator cX = ObjectAnimator . ofFloat ( this , "xGravity" , 1 ) ; cX . setAutoCancel ( true ) ; cX . setDuration ( radiusDuration ) ; cX . setInterpolator ( LINEAR_INTERPOLATOR ) ; cX . setStartDelay ( RIPPLE_ENTER_DELAY ) ; final ObjectAnimator cY = ObjectAnimator . ofFloat ( this , "yGravity" , 1 ) ; cY . setAutoCancel ( true ) ; cY . setDuration ( radiusDuration ) ; cY . setInterpolator ( LINEAR_INTERPOLATOR ) ; cY . setStartDelay ( RIPPLE_ENTER_DELAY ) ; mAnimRadius = radius ; mAnimX = cX ; mAnimY = cY ; radius . start ( ) ; cX . start ( ) ; cY . start ( ) ; }
starts the enter animation .
