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

在某些情况下,当您在视图中放置和移动UI元素(特别是以编程方式绘制的自定义元素)时,关闭受影响视图中的自动布局会导致此错误消失。当我发现这个症状时,我正在使用JVFloatLabeledTextField。

其他回答

在我的情况下,我在这段代码中有这些错误:

CAShapeLayer *shapeLayer = [CAShapeLayer layer];
UIBezierPath *path;

path = [UIBezierPath bezierPath];
[path moveToPoint:CGPointMake(0, 0)];
[path addLineToPoint:CGPointMake(size*2, 0)];
[path addLineToPoint:CGPointMake(size, size*2)];
[path closePath];
[path fill];

shapeLayer.path = path.CGPath;
shapeLayer.strokeColor = [[UIColor blackColor] CGColor];
shapeLayer.fillColor = color;
shapeLayer.lineWidth = width;

[self addSublayer:shapeLayer];

经过一些思考和测试,我发现了问题——这是一个电话:

[path fill];

正如我检测到的-在我的代码中,这个调用是不必要的,因为填充将通过其他方式完成-所以我简单地删除它。

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。

我有这个问题在一个UITextField,当我持有一个空白字段与占位符文本的触摸。我使用以下方法来消除空白字段:

-(void)textFieldDidBeginEditing:(UITextField *)textField{

        textField.text=[@" " stringByAppendingString:textField.text];

        //other stuff here
}


-(BOOL)textFieldShouldReturn:(UITextField *)textField{

         if(textField.text.length>0){
             if([[textField.text substringToIndex:1] isEqualToString:@" "])
                 textField.text=[textField.text substringFromIndex:1];
         }
         //  other stuff here
}

在某些情况下,你可能需要包含一行#import <QuartzCore/QuartzCore.h>。

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