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

我使用下面的代码从上下文创建UIImage:

    UIGraphicsBeginImageContext(size);
    CGContextRef context = UIGraphicsGetCurrentContext();

    CGContextSetFillColorWithColor(context, color.CGColor);
    CGContextFillRect(context, (CGRect){.size = size});

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

这样我就得到了错误。

所以我删除了派生数据内容,重新启动XCode。这招奏效了。

其他回答

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,我得到这个错误,因为我正在释放CGContextRef,如下所示:

- (void)drawRect:(CGRect)rect
{
    CGContextRef context = UIGraphicsGetCurrentContext();

    // DRAW BACKGROUND CIRCLE
    CGContextSetFillColorWithColor(context, [[UIColor gray] colorWithAlphaComponent:0.6].CGColor);
    CGContextFillEllipseInRect(context, rect);

//    CGContextRelease(context);
}

删除版本解决了这个问题

这有点俗气,但对我很管用。

我在UITableViewCell的init中设置了UIImageView,给它一个大小和约束。

然后在我的视图控制器的cellForRowAtIndexPath中我这样做:

let img = PFImageView(frame: CGRect(x: 0, y: 0, width: 50, height: 50))
img.setImage(withFile: nil, defaultText: message.senderUsername)
cell.profileImageView?.image = img.image

这避免了错误,在函数下面,我为UIImageView设置了实际图像。上面的代码是一个很好的默认值

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。

当我在UIActivity子类的activityImage方法中输入错误的图像名称时,我得到了它

- (UIImage *)activityImage
{
    return [UIImage imageNamed:@"img.png"];
}

输入正确的图像为我解决了这个问题。