UIGraphicsBeginImageContext如何设置位置？

Question

我在我的应用程序中截图。我可以截取屏幕截图，但现在我想通过指定x和y坐标来获取屏幕截图。我的意思是从y = 40开始截图。那可能吗？

UIGraphicsBeginImageContext(screenshot.frame.size); 
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()]; 
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext(); 
UIGraphicsEndImageContext(); 

Answer 1

UIGraphicsBeginImageContext(screenshot.frame.size); 
CGImageRef imageRef = CGImageCreateWithImageInRect((CGImageRef)self.view.layer.contents, cropRect); 
UIImage *image = [UIImage imageWithCGImage:imageRef]; 
CGImageRelease(imageRef); 
[image drawInRect:CGRectMake(...)]; 
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext(); 
UIGraphicsEndImageContext();