在UIScrollView内的UIImageView中添加捏/缩放效果 [英] Adding Pinch/Zoom effect to a UIImageView inside a UIScrollView

问题描述

我有一个非常基本的屏幕共享iPhone应用程序，我已经使用 UIScrollView 内的 UIImageView 将捏/缩放效果成功添加到了我的应用程序中.

I have a very basic screen sharing iPhone app, I have successfully added the pinch/zoom effect to my app using a UIImageView inside a UIScrollView.

UIImageView 定期接收来自PC的屏幕内容.一切都正常，但是一旦我滚动/捏/缩放就可以了，但随后它停止了，即使服务器仍然发送屏幕内容，更新图像视图内容的委托方法也停止启动.整个应用似乎被冻结了，但是没有错误消息/异常/任何信息.有人可以帮我吗?

The UIImageView receives the screen content from the PC on a regular interval. Everything works fine but as soon as I scroll/pinch/zoom it works at first but then it stops, and the delegate method that's updating the image view content stops firing up even though the server still sends the screen content. The whole app seems to be frozen but there are no error messages/exceptions/whatever. Can anyone help me, please?

推荐答案

如果使用的是 NSDefaultRunLoopMode ，则 UIAPPlication 会添加运行循环模式 UITrackingRunLoopMode 用于跟踪滚动等滚动视图事件.由于 UIApplication 从 NSDefaultRunLoopMode 切换到 UITrackingRunLoopMode ，因此直到 UIAPPlication 切换回 NSDefaultRunLoopMode .

If you are using NSDefaultRunLoopMode, UIAPPlication adds a run loop mode UITrackingRunLoopMode for tracking scrollview events like scrolling. Since the UIApplication switches from NSDefaultRunLoopMode to UITrackingRunLoopMode any events on NSDefaultRunLoopMode will not be called until UIAPPlication switch back to NSDefaultRunLoopMode.

可能是问题所在，解决方法是将 NSDefaultRunLoopMode 更改为 NSRunLoopCommonModes .

It might be the problem, the fix is change NSDefaultRunLoopMode to NSRunLoopCommonModes .

如果您不确定是否正在使用runloop(如注释中所述).只需在您的项目中搜索 NSDefaultRunLoopMode .

If you are not sure whether you are using runloop or not as you mentioned in comment. Just search NSDefaultRunLoopMode in your project.

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