iOS 5核心数据冻结 [英] iOS 5 Core Data freeze

问题描述

我尝试做以下简单的事情：

  NSArray * entities = [context executeFetchRequest：inFetchRequest error：& fetchError ]; 
  

没什么好奇的。但是这在iOS 5中冻结，它在iOS 4正常工作。我不会得到异常，警告或错误;我的应用程序只是冻结。

请帮助我！我在这里死了！ ;）

解决方案

感谢此页面提供的有关如何解决从iOS4升级时出现的冻结问题的提示。这是我从iOS开始编程以来发现的最恼人的问题。

我发现了一个快速的解决方案，其中只有几个调用上下文

 
 code> [self performSelectorOnMainThread：@selector（stateChangeOnMainThread :) withObject：[NSDictionary dictionaryWithObjectsAndKeys：state，@state，nil] waitUntilDone：YES]; 
 

要检测从另一个线程调用上下文的地方，可以在NSLog上放置一个断点

 <$ c $ 
 c> if（！[NSThread isMainThread]）{
 NSLog（@不是主线程...）; 
} 
  

我希望这可能会有所帮助...

I try to do the following simple thing:

NSArray * entities = [context executeFetchRequest:inFetchRequest error:&fetchError];

Nothing fancy. But this freezes in iOS 5, it works fine in iOS 4. I don't get exceptions, warnings or errors; my app just simply freezes.

Please help me out! I'm dying here! ;)

解决方案

Thanks for the hints given in this page on how to solve this freezing issue which appeared on upgrading from iOS4. It has been the most annoying problem I have found since I started programming on iOS.

I have found a quick solution for cases where there are just a few calls to the context from other threads.

I just use performSelectorOnMainThread:

    [self performSelectorOnMainThread:@selector(stateChangeOnMainThread:) withObject: [NSDictionary dictionaryWithObjectsAndKeys:state, @"state", nil] waitUntilDone:YES];

To detect the places where the context is called from another thread you can put a breakpoint on the NSLog on the functions where you call the context as in the following piece of code and just use performSelectorOnMainThread on them.

if(![NSThread isMainThread]){
     NSLog(@"Not the main thread...");
}

I hope that this may be helpful...

这篇关于iOS 5核心数据冻结的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！