Ios 手势识别器的子视图实现应开始：干扰父视图'；这是该方法的实现

我有一个ParentViewController，它的视图有一个子视图。我希望ParentViewController有机会在其视图中评估手势，并且只有在这些手势失败时，子视图才有机会评估手势。但是相反，事情似乎朝着相反的方向发展，子视图实际上是在评估属于父视图的挤压手势。下面是如何设置的：

ParentViewController有一个夹点手势识别器，其委托设置为ParentViewController：

pinchRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(handlePinch:)];
pinchRecognizer.delegate = self;
[self.view addGestureRecognizer:pinchRecognizer];

ParentViewController实现

UIgestureRecognitizerDelegate

协议，具体实现方法

gestureRecognitizerShouldBegin:

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer  //DEPENDENCY
{
    return [gestureRecognizer isKindOfClass:[UIPinchGestureRecognizer class]];
}

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
    if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
        CGPoint translation = [(UIPanGestureRecognizer *)gestureRecognizer translationInView:[self superview]];
        return (fabsf(translation.x) > fabsf(translation.y) && translation.x < 0);
    } else if ([gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]]) {
        return YES;
    }
    return NO;
}

ParentViewController的视图有一个子视图。子视图具有轻触手势识别器和平移识别器：

_tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(stepTapped:)];
[self addGestureRecognizer:_tapRecognizer];
_tapRecognizer.numberOfTapsRequired = 1;
_tapRecognizer.delegate = self;

_panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)];
[self addGestureRecognizer:_panRecognizer];
_panRecognizer.maximumNumberOfTouches = 1;
_panRecognizer.delegate = self;

子视图还实现了

UIGestureRecognitizerDelegate

协议，具体实现了方法

GestureRecognitizerShouldBegin:

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer  //DEPENDENCY
{
    return [gestureRecognizer isKindOfClass:[UIPinchGestureRecognizer class]];
}

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
    if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]]) {
        CGPoint translation = [(UIPanGestureRecognizer *)gestureRecognizer translationInView:[self superview]];
        return (fabsf(translation.x) > fabsf(translation.y) && translation.x < 0);
    } else if ([gestureRecognizer isKindOfClass:[UITapGestureRecognizer class]]) {
        return YES;
    }
    return NO;
}

尽管有最后两行代码，但我发现子视图的

gestureRecognitzerBegin:

方法在ParentViewController之前被调用。此外，ParentViewController中的

手势识别器的实现应该开始：

甚至不会运行，除非我修改子视图的实现，在发生挤压手势时返回

YES

（参见最后一行）：

-（BOOL）手势识别器应开始：（uigesturecognizer*）手势识别器
{
if（[GestureRecognitor IsKindof类：[UIPangestureRecognitor类]]）{
CGPoint translation=[（UIPangestureRecognitor*）手势识别器translationView:[自我超级视图]]；
返回（fabsf（translation.x）>fabsf（translation.y）&&translation.x<0）；
}else if（[GestureRecognitor IsKindof类：[UITapGestureRecognitor类]]）{
返回YES；
}
return[gestureRecognizer isKindOfClass:[UIPinchGestureRecognizer class]]；
}

使用上述代码，子视图的

手势识别器应该开始：

运行，如果是捏手势，则在最后返回

YES

时，将调用ParentViewController的

手势识别器应该开始：

如果不清楚，我期望的行为是ParentViewController的

手势识别器应该首先被调用：

，只有在失败时才会调用子视图的实现