常用礼物数字combo动画

/**
 添加礼物数字的动画
 */
- (void)addComboAnimation{
    if (CGAffineTransformIsIdentity(self.numberImgView.transform) ) {
        // 没有正在播放的动画
        dispatch_async(dispatch_get_main_queue(), ^{
            [self _animateGiftNumImg];
        });
    } else {
        // 有正在播放的动画, 就延迟
        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
            [self _animateGiftNumImg];
        });
    }
}

/**
 礼物数字图片先放大然后回归正常
 */
- (void)_animateGiftNumImg {
    UIView *comboView = self.numberImgView.rootView;
    comboView.transform = CGAffineTransformIdentity;
    [UIView animateWithDuration:0.1 animations:^{
        // 放大
        comboView.transform = CGAffineTransformMakeScale(5, 5);
    } completion:^(BOOL finished) {
        [UIView animateWithDuration:0.1 animations:^{
            // 复原
            comboView.transform = CGAffineTransformIdentity;
        }];
    }];
}