在我的应用程序中,我在控制台中收到以下错误:
May 1 22:06:59 iPhone-4S app[93660] <Error>: CGContextAddPath: invalid context 0x0
May 1 22:06:59 iPhone-4S app[93660] <Error>: clip: invalid context 0x0
唯一可能发生这种情况的区域是以下两种方法之一,用于调整 UIImage 的大小或添加圆角边缘。以下是方法:
- (UIImage*)imageWithImage:(UIImage*)image scaledToSize:(CGSize)newSize {
// Create a graphics image context
UIGraphicsBeginImageContext(newSize);
// Tell the old image to draw in this new context, with the desired
// new size
[image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
// Get the new image from the context
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
// End the context
UIGraphicsEndImageContext();
// Return the new image.
return newImage;
}
- (UIImage*)roundCorneredImage: (UIImage*)orig radius:(CGFloat) r {
UIGraphicsBeginImageContextWithOptions(orig.size, NO, 0);
[[UIBezierPath bezierPathWithRoundedRect:(CGRect){CGPointZero, orig.size}
cornerRadius:r] addClip];
[orig drawInRect:(CGRect){CGPointZero, orig.size}];
UIImage* result = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return result;
}
这两种方法都是从 UIViewControllers 中调用的,我很肯定 UIImage 不为零。
发生这种情况有什么原因吗?
谢谢!