关于这个可怕的问题,我已经阅读了尽可能多的搜索结果,不幸的是,每个搜索结果似乎都集中在一个特定的函数调用上。

我的问题是,我从多个函数得到相同的错误,我猜是从我使用的函数回调的。

更糟糕的是,实际的代码是在另一个项目中导入的自定义私有框架中,因此,调试不是那么简单吗?

有人能告诉我正确的方向吗?我有一种感觉,我正在错误地调用某些方法或与坏的上下文,但xcode的输出在这一点上不是很有帮助。

: CGContextSetFillColorWithColor: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. : CGContextSetStrokeColorWithColor: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. CGContextSaveGState: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. : CGContextSetFlatness: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. : CGContextAddPath: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. : CGContextDrawPath: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. : CGContextRestoreGState: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update. : CGContextGetBlendMode: invalid context 0x0. This is a serious error. This application, or a library it uses, is using an invalid context and is thereby contributing to an overall degradation of system stability and reliability. This notice is a courtesy: please fix this problem. It will become a fatal error in an upcoming update.

当呈现自定义视图或其继承的类之一时,可能会发生这些错误。这时它们会生成多次,直到键盘不再提供任何输入。触摸事件仍然被注册,但是系统变慢,最终可能导致未分配对象错误。

编辑#1:我确实可以访问正在导入的框架,但我没有看到导致问题的类中有任何奇怪的东西。

编辑#2:我刚刚收到一封电子邮件,iOS 7.1已经发布给开发者了。我很好奇这种情况是否会消失,或者变得更糟,或者是否能得到解决。


当前回答

从模拟器卸载应用程序,并再次运行

其他回答

其他人会要求你在访问核心图形上下文的地方发布代码,但我怀疑这是问题所在。这些无效的上下文0x0错误消息很常见,很容易在iOS 7中重现。事实上,我可以使用零代码的故事板重现错误。我在IB中拖动UITextField到画布上,运行应用程序,双击文本字段内。

在许多情况下,我很难认真对待无效上下文0x0错误消息。我不知道您的情况是否值得更大的关注(我同意Rob Napier的观点,这是值得研究的,特别是如果您显式地使用图形上下文)。

在我自己的项目中,我希望有一天这些错误会神奇地消失(但这一天并没有伴随着7.0.3)。

更新:在安装Xcode 5.1并瞄准iOS 7.1后,我再也不能通过双击空文本字段来重现错误。

如果在使用UIBezierPath并为描边或填充设置颜色时发生错误,请将设置的颜色代码放在drawRect函数中而不是其他地方。

这些类型的错误是历史上调用核心图形函数的结果,而不是在一个上下文中建立的drawRect或调用之间,如UIGraphicsBeginImageContext和UIGraphicsEndImageContext(或其他UIKit函数,如开始和结束一个上下文)。

话虽如此,但bilobatum说的没错,这一系列错误可能是他在回答中提到的iOS 7漏洞造成的。如果在你的iOS6目标中没有看到这些错误,或者在快速扫描这个私有框架后,你没有发现任何可疑的核心图形调用,这可能只是iOS 7的错误。接得好,双叶巴坦!

对我来说,答案是我不必要地释放了drawRect:中的图形上下文。在CGPostError上抛出一个符号断点使我找到了罪魁祸首。

如果您想知道是什么代码导致了这些日志,可以在CGPostError上添加一个符号断点。