我想要将屏幕上的图像截屏并保存到照片库中。
如果要检查是否为视网膜显示器,请使用以下代码片段:
#import <QuartzCore/QuartzCore.h>
if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) {
UIGraphicsBeginImageContextWithOptions(self.window.bounds.size, NO, [UIScreen mainScreen].scale);
} else {
UIGraphicsBeginImageContext(self.window.bounds.size);
}
[self.window.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData *imageData = UIImagePNGRepresentation(image);
if (imageData) {
[imageData writeToFile:@"screenshot.png" atomically:YES];
} else {
NSLog(@"error while taking screenshot");
}
以下方法也适用于OPENGL对象
//iOS7 or above
- (UIImage *) screenshot {
CGSize size = CGSizeMake(your_width, your_height);
UIGraphicsBeginImageContextWithOptions(size, NO, [UIScreen mainScreen].scale);
CGRect rec = CGRectMake(0, 0, your_width, your_height);
[_viewController.view drawViewHierarchyInRect:rec afterScreenUpdates:YES];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
UIGetScreenImage
是一个私有 API。 - jonahbUIGraphicsBeginImageContextWithOptions(self.view.bounds.size, self.view.opaque, 0.0);
[self.myView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData *imageData = UIImageJPEGRepresentation(image, 1.0 ); //you can use PNG too
[imageData writeToFile:@"image1.jpeg" atomically:YES];
- (UIImage*) getGLScreenshot {
NSInteger myDataLength = 320 * 480 * 4;
// allocate array and read pixels into it.
GLubyte *buffer = (GLubyte *) malloc(myDataLength);
glReadPixels(0, 0, 320, 480, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
// gl renders "upside down" so swap top to bottom into new array.
// there's gotta be a better way, but this works.
GLubyte *buffer2 = (GLubyte *) malloc(myDataLength);
for(int y = 0; y <480; y++)
{
for(int x = 0; x <320 * 4; x++)
{
buffer2[(479 - y) * 320 * 4 + x] = buffer[y * 4 * 320 + x];
}
}
// make data provider with data.
CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, buffer2, myDataLength, NULL);
// prep the ingredients
int bitsPerComponent = 8;
int bitsPerPixel = 32;
int bytesPerRow = 4 * 320;
CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB();
CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault;
CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault;
// make the cgimage
CGImageRef imageRef = CGImageCreate(320, 480, bitsPerComponent, bitsPerPixel, bytesPerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent);
// then make the uiimage from that
UIImage *myImage = [UIImage imageWithCGImage:imageRef];
return myImage;
}
- (void)saveGLScreenshotToPhotosAlbum {
UIImageWriteToSavedPhotosAlbum([self getGLScreenshot], nil, nil, nil);
}
来源。
UIImage *myImage = [[UIImage alloc] initWithCGImage:imageRef scale:1.0 orientation:UIImageOrientationDownMirrored];
,这样就不需要'buffer2'了。顺便提醒一下,看起来你忘记了内存管理,没有使用free()或者release()... - Oleg Trakhman使用 Swift 语言
func captureScreen() -> UIImage
{
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, false, 0);
self.view.drawViewHierarchyInRect(view.bounds, afterScreenUpdates: true)
let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return image
}
iOS10 版本以后,这变得更加简单了。UIKit 提供了 UIGraphicsImageRenderer
,让你能够完成绘图任务,而不需要处理像色深和图片缩放这样的配置,或者管理 Core Graphics 上下文。
...就像完成绘图任务一样,而无需处理如颜色深度和图像比例等配置,也无需管理 Core Graphics 上下文。
Apple Docs - UIGraphicsImageRenderer
现在你可以这样做:
let renderer = UIGraphicsImageRenderer(size: someView.bounds.size)
let image = renderer.image(actions: { context in
someView.drawHierarchy(in: someView.bounds, afterScreenUpdates: true)
})
这里的许多回答在大多数情况下对我都有效。但是当尝试拍摄ARSCNView
的快照时,我只能使用上述方法来完成。虽然值得注意的是此时ARKit仍处于beta版,Xcode也处于beta 4版。
-(UIImage *)capture{
UIGraphicsBeginImageContext(self.view.bounds.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *imageView = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(imageView, nil, nil, nil); //if you need to save
return imageView;
}
如果您想要全屏显示(除状态栏外),我认为以下代码片段会对您有所帮助。如有需要,请将AppDelegate替换为您的应用代理名称。
- (UIImage *)captureFullScreen {
AppDelegate *_appDelegate = (AppDelegate *)[UIApplication sharedApplication].delegate;
if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) {
// for retina-display
UIGraphicsBeginImageContextWithOptions(_appDelegate.window.bounds.size, NO, [UIScreen mainScreen].scale);
[_appDelegate.window drawViewHierarchyInRect:_appDelegate.window.bounds afterScreenUpdates:NO];
} else {
// non-retina-display
UIGraphicsBeginImageContext(_bodyView.bounds.size);
[_appDelegate.window drawViewHierarchyInRect:_appDelegate.window.bounds afterScreenUpdates:NO];
}
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
我回答这个问题是因为它被高度关注,并且有许多答案,还有Swift和Obj-C。
免责声明这不是我的代码,也不是我的答案,只是为了帮助来到这里的人快速找到答案。有原始答案的链接,以便给予应有的荣誉!如果您使用他们的答案,请通过+1来尊重原始答案!
#import <QuartzCore/QuartzCore.h>
if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) {
UIGraphicsBeginImageContextWithOptions(self.window.bounds.size, NO, [UIScreen mainScreen].scale);
} else {
UIGraphicsBeginImageContext(self.window.bounds.size);
}
[self.window.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData *imageData = UIImagePNGRepresentation(image);
if (imageData) {
[imageData writeToFile:@"screenshot.png" atomically:YES];
} else {
NSLog(@"error while taking screenshot");
}
func captureScreen() -> UIImage
{
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, false, 0);
self.view.drawViewHierarchyInRect(view.bounds, afterScreenUpdates: true)
let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return image
}