shouldReceiveTouch 和 gestureRecognizerShouldBegin 的差异

获取到的view不同

shouldReceiveTouch 方法中，获取到的touch.view是手指触摸到的最上层的视图，

gestureRecognizerShouldBegin 获取到的是 手势添加到的视图

- (void)viewDidLoad {
    [super viewDidLoad];
    [self.view addSubview:self.tableView];
    [self.view addGestureRecognizer:self.pangesture];
    // Do any additional setup after loading the view.
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
    NSLog(@"哈哈哈哈哈合获取获取shouldReceiveTouch获取到的view%@", touch.view);
    return YES;
    
}

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
    NSLog(@"gestureRecognizerShouldBegin获取到的view%@", gestureRecognizer.view);
    if (gestureRecognizer == self.pangesture) {
        self.panNum ++;
    }
    return YES;
}

打印结果

由此可见，我们如果想要获取手指触摸的视图，必须要通过shouldReceiveTouch 方法，
用法，比如我们在类似抖音评论弹窗视图中，就可以通过这个
方法获取到我们当前滑动的是弹窗中的tableView，还是弹窗本身的视图
如下代码

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
    if (gestureRecognizer == self.panGesture) {
        UIView *touchView = touch.view;
        while (touchView != nil) {
            if ([touchView isKindOfClass:[UIScrollView class]]) {
                self.scrollView = (UIScrollView *)touchView;
                self.isDragScrollView = YES;
                break;
            }else if (touchView == self.containerView) {
                self.isDragScrollView = NO;
                break;
            }
            touchView = (UIView *)[touchView nextResponder];
        }
    }
    return YES;
}

执行的先后顺序

shouldReceiveTouch 方法是在gestureRecognizerShouldBegin 方法之前的