public static int getAnimationResource(int gravity, boolean isInAnimation)
	{
		switch (gravity)
		{
		case Gravity.BOTTOM:
			return isInAnimation ? R.anim.slide_in_bottom : R.anim.slide_out_bottom;
		}
		return INVALID;
	}
Get default animation resource when not defined by the user

@param gravity
           the gravity of the dialog
@param isInAnimation
           determine if is in or out animation. true when is is
@return the id of the animation resource
app/src/main/java/home/smart/fly/animations/customview/wheel/widget/utils/PickerViewAnimateUtil.java