iOS-解决手势冲突

最近的项目中里面有一个需求，UIScrollerView 上面放了一个横向滑动的UICollectionView, 在UICollectionView滑动到最右侧的时候，底部的UIScrollerView响应滑动手势，继续向右切换，

Apple 提供解决双重手势的方法

// return YES to allow both to recognize simultaneously. the default implementation returns NO (by default no two gestures can be recognized simultaneously)

// 翻译过来就是：返回YES以允许两者同时识别。 默认实现返回NO（默认情况下，不能同时识别两个手势）， 但是有些时候不需要都识别，需要达到特定条件才可以识别滑动收拾，就需要特殊处理
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer

说一下我的问题的解决方案：

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
    
    if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
        
        UIPanGestureRecognizer *panGes = (UIPanGestureRecognizer *)gestureRecognizer;
        
        CGPoint velocity = [panGes velocityInView:panGes.view];
        
        if ([gestureRecognizer.view isKindOfClass:[UIScrollView class]]) {
            
            // 使用 velocity.x < 0 判断向右滑动的时候
            if (gestureRecognizer.state == UIGestureRecognizerStateBegan && self.contentOffset.x >= floor(maxDistance) && velocity.x < 0) {
                
                return YES;
            }   
        }
    }
    return NO;
}