How to Take Screenshots Programmatically?

Today I’ve been playing a bit Jetpack Joyride, game is really cool and I noticed one nice detail in game: as you finish game you get option to take a look at gameplay screenshot and if you like it you can save it to your photo album. This gave me an idea to write a blog how to take screenshot programmatically and how to save this image in user photo album.

Open some existing project or create new project and place some content on screen, when you take screenshot you’ll see this content on image. You can also place some UIButton on screen and define IBAction for taking screenshot.

Add QuartzCore framework to your project:

and import QuartzCore header file:

#import <QuartzCore/QuartzCore.h>

Taking screenshot is done in few simple steps: you need to create new image context, retrieve current graphics context, render view into this context and create UIImage out of it. This UIImage we’ll save in photo album:

// create new image context
UIGraphicsBeginImageContext(self.view.bounds.size);

// retrieve the current graphics context
 CGContextRef context = UIGraphicsGetCurrentContext();

// render view into context
 [self.view.layer renderInContext:context];

// create image from context
 UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
 UIGraphicsEndImageContext();

// save image to photo album
 UIImageWriteToSavedPhotosAlbum(image,
 self,
 @selector(image:didFinishSavingWithError:contextInfo:),
 NULL);

UIImageWriteToSavedPhotosAlbum function have completion selector defined, that way we’ll know was image saved successfully or some error occurred:

- (void)image:(UIImage*)image
 didFinishSavingWithError:(NSError*)error
 contextInfo:(void*)contextInfo
 {
 if (error == nil)
 NSLog(@"Image saved successfully.");
 else
 NSLog(@"Error occurred:%@",[error localizedDescription]);
 }

Thanks for reading!