Take Screenshots Programatically in iOS with Category on UIViewController

Thought I’d share this almost-trivial technique for taking screenshots of an iOS device. This will essentially replicate the user pressing the home & power buttons simultaneously, but will return a UIImage for you to use as you please.

Without further ado:

UIViewController+Screenshot.h

#import <Foundation/Foundation.h>

@interface UIViewController (Screenshot)

- (UIImage *)takeScreenshot;

@end

UIViewController+Screenshot.m

#import "UIViewController+Screenshot.h"

@implementation UIViewController (Screenshot)

- (UIImage *)takeScreenshot {
    CGRect rect = self.view.bounds;

    UIGraphicsBeginImageContext(rect.size);

    CGContextRef context = UIGraphicsGetCurrentContext();

    [self.view.layer renderInContext:context];

    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    return img;
}

@end

To make use of this, create these two files (or download them here) and add them to your project. Import the UIViewController+Screenshot.h file as needed.

Here’s a quick usage example:

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];

    UIImage *screenshot = [self takeScreenshot];
    NSString *screenshotPath = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents/Screenshots"];
    BOOL isDir;
    __autoreleasing NSError *error;
    NSFileManager *fm = [NSFileManager defaultManager];
    
    if (!([fm fileExistsAtPath:screenshotPath isDirectory:&isDir] && isDir)) {
        if (![fm createDirectoryAtPath:screenshotPath
           withIntermediateDirectories:YES
                            attributes:nil
                                 error:&error]) {
            NSLog(@"Couldn't create screenshot directory. Error: %@", error);
            return;
        }
    }

    NSDateFormatter *df = [[NSDateFormatter alloc] init];
    df.dateFormat = @"yyyyMMddHHmmss";

    screenshotPath = 
        [screenshotPath stringByAppendingPathComponent:
                            [NSString stringWithFormat:@"Screenshot_%@.jpg",
                [UIImageJPEGRepresentation(screenshot, 0.5) 
                                           writeToFile:screenshotPath
                                            atomically:YES];
}

Pretty self-explanatory, I think. Adjust to suit your needs, such as a different path for the images or a different ‘quality’ level for the resultant JPEG file (we’re using 0.5 here).

Hope somebody finds this useful!

UPDATE: NEVER MIND!!!