GestureRecognizer的子类不起作用

Question

我正在尝试将手势识别器子类化以检测触摸，而不是触摸。 子类化工作正常，只有当我没有把这行放到启用滚动时：

[touchDown requireGestureRecognizerToFail:scroller.panGestureRecognizer];

子类实现：

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    if (self.state == UIGestureRecognizerStatePossible)
    {
        self.state = UIGestureRecognizerStateRecognized;
    }
}

问题是，我需要那行，否则滚动条不会移动..

实施：

 TouchDownGestureRecognizer *touchDown = [[TouchDownGestureRecognizer alloc] initWithTarget:self action:@selector(handleTouchDown:)];
    [scroller addGestureRecognizer:touchDown];
    [touchDown requireGestureRecognizerToFail:scroller.panGestureRecognizer];//not work with it.

Answer 1

启用滚动条的解决方案：

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
     return YES;
}