UIScrollView防止touchesBegan，touchesMoved，touchesEnd在视图控制器上结束 [英] UIScrollView prevents touchesBegan, touchesMoved, touchesEnded on view controller

问题描述

我正在处理视图控制器(UIViewController的自定义子类)中的几个UI组件的触摸.它具有方法 touchesBegan:withEvent:， touchesMoved:withEvent:和 touchesEnded:withEvent:.工作正常.然后，我添加了一个滚动视图(UIScrollView)作为层次结构中的顶视图.

I am handling touches for a couple of my UI components in my view controller (custom subclass of UIViewController). It has methods touchesBegan:withEvent:, touchesMoved:withEvent:, and touchesEnded:withEvent:. It was working fine. Then I added a scroll view (UIScrollView) as the top view in the hierarchy.

现在，我在视图控制器上的触摸处理程序无法正常工作.他们不被叫.有趣的是，我在滚动视图中还有其他可以工作的UI组件.有些是按钮，有些是定义自己的 touchesBegan:withEvent:的自定义视图，等等.唯一不起作用的是视图控制器上的触摸处理程序.

Now my touch handlers on the view controller don't work. They don't get called. The interesting thing is, I have various other UI components within the scroll view that do work. Some are buttons, some are custom views that define their own touchesBegan:withEvent:, etc. The only thing that doesn't work is the touch handlers on the view controller.

我认为可能是因为滚动视图出于其自身目的拦截了这些触摸，但是我将UIScrollView子类化，只是为了查看是否可以正常使用，我总是从返回 YES > touchesShouldBegin:withEvent:inContentView:和 NO 始终来自 touchesShouldCancelInContentView:.仍然不起作用.

I thought maybe it's because the scroll view is intercepting those touches for its own purposes, but I subclassed UIScrollView and just to see if I could get it to work I am returning YES always from touchesShouldBegin:withEvent:inContentView: and NO always from touchesShouldCancelInContentView:. Still doesn't work.

如果有所作为，我的视图控制器位于选项卡栏控制器内，但我认为这无关紧要.

If it makes a difference my view controller is within a tab bar controller, but I don't think it's relevant.

有人有这个问题并且有现成的解决方案吗?我的猜测是滚动视图使响应者链条monkey绕.我可以回头吗?我想，如果我无法弄清楚其他任何事情，我将使滚动视图下的顶层视图成为自定义视图，并将消息转发到视图控制器，但是看起来很笨拙.

Has anyone had this problem and have a ready solution? My guess is the scroll view monkeys up the responder chain. Can I monkey it back? I guess if I can't figure anything else out I'll make the top level view under my scroll view be a custom view and forward the messages on to the view controller, but seems kludgy.

推荐答案

创建UIScrollView类的子类，并覆盖touchesBegan:和其他touch方法，如下所示:

create a subclass of UIScrollView class and override the touchesBegan: and other touch methods as follows:

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{

// If not dragging, send event to next responder
  if (!self.dragging){ 
    [self.nextResponder touchesBegan: touches withEvent:event]; 
  }
  else{
    [super touchesBegan: touches withEvent: event];
  }
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{

// If not dragging, send event to next responder
    if (!self.dragging){ 
     [self.nextResponder touchesMoved: touches withEvent:event]; 
   }
   else{
     [super touchesMoved: touches withEvent: event];
   }
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{

  // If not dragging, send event to next responder
   if (!self.dragging){ 
     [self.nextResponder touchesEnded: touches withEvent:event]; 
   }
   else{
     [super touchesEnded: touches withEvent: event];
   }
}

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