Question

我有UIView同时使用UIKit控件和OpenGL。我想以编程方式获得该视图的屏幕截图。

如果我使用UIGraphicsGetImageFromCurrentImageContext()，则OpenGL内容为空; 如果我使用glReadPixels(...)方法，则UIKit内容为空;

我对如何拍摄完整的屏幕截图感到困惑。谢谢！

Answer 1

使用以下代码进行截屏

    -(UIImage *) screenshot
     {

          CGRect rect;
          rect=CGRectMake(0, 0, 320, 480);
          UIGraphicsBeginImageContext(rect.size);

          CGContextRef context=UIGraphicsGetCurrentContext();
          [self.view.layer renderInContext:context];

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

          return image;
     }

Answer 2

-(UIImage *) screenshot
{
CGImageRef UIGetScreenImage(void);
CGImageRef screen = UIGetScreenImage();
UIImage* screenImage = [UIImage imageWithCGImage:screen];
CGImageRelease(screen); // you need to call this.
return screenImage;
}

Answer 3

嗯，以编程方式捕捉iPhone屏幕的方法很少

使用UIKIT http://developer.apple.com/library/ios/#qa/qa1703/_index.html
使用AVFoundation框架http://developer.apple.com/library/ios/#qa/qa1702/_index.html
使用OpenGL ES http://developer.apple.com/library/ios/#qa/qa1704/_index.html
从iOS 7开始，您还可以使用Why does my programmatically created screenshot look so bad on iOS 7?

使用UIWindow

CGRect screenRect = [[UIScreen mainScreen] bounds];
UIGraphicsBeginImageContext(screenRect.size);
CGContextRef ctx = UIGraphicsGetCurrentContext();
[[UIColor blackColor] set];
CGContextFillRect(ctx, screenRect);
[self.window.layer renderInContext:ctx];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

使用UIView

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

在这6个选项中，我发现第一个选项非常方便用于复制粘贴和应用压缩级别，因为1st方法为图像提供了真实的像素数据。我也喜欢选项4，因为API附带了SDK。

Answer 4

您可以获得结果Uiimage而不会丢失图像质量

    - (UIImage *)captureView:(UIView *)view {
     UIGraphicsBeginImageContextWithOptions(view.bounds.size, view.opaque, 0.0);
     [view.layer renderInContext:UIGraphicsGetCurrentContext()];
     UIImage * img = UIGraphicsGetImageFromCurrentImageContext();
     UIGraphicsEndImageContext();
     return img;
     }

Answer 5

UIGraphicsBeginImageContext(self.view.bounds.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData *data = [UIImagePNGRepresentation(image) retain];
UImage *screenShot = [UIImage imageWithData:data];

Answer 6

以下是如何以编程方式对UIImage进行简单截屏。如果您希望它替换任何其他对象，请将UIImage替换为它。

在.h文件中添加NSData *Data;，然后在.m文件中将此添加到您的代码中

UIGraphicsBeginImageContext(self.view.frame.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *attachimage = [[UIImage alloc]initWithData:Data];
UIImage *viImage=UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
attachimage = viImage;
UIImageWriteToSavedPhotosAlbum(viImage, nil, nil, nil);

Answer 7

您知道OpenGL内容在视图中的位置。因此，将glReadPixels的结果复制到UIKit的快照中应该很容易。

Answer 8

也许..你可以使用这里的东西

- https://stackoverflow.com/questions/12413460/cocos2d-2-0-screenshots-on-ios-6

在这里......

Why is glReadPixels() failing in this code in iOS 6.0?

如何在iOS中以编程方式截取屏幕截图？

8 个答案: