code: public TouchActions flick(int xSpeed, int ySpeed) {
      if (touchScreen != null) {
        action.addAction(new FlickAction(touchScreen, xSpeed, ySpeed));
      }
      return this;
    }
docs: Sends a flick gesture to the current view.
  
  @param xSpeed The horizontal speed in pixels/second
  @param ySpeed The vertical speed in pixels/second
  @return self