(iOS) Take image snapshots of the current state of a view.

UIView+Snapshots.m

@interface UIView (UIView_Snapshots)

// Take image snapshots of the current state of a view.

// Use the background color of the superview if you have rounded corners
// If background color is nil the background will be treated as transparent
- (UIImage*) imageOfViewUsingBackgroundColor:(UIColor*)backgroundColorOrNil;

// Will save to the documents directory as XXXX.png
- (void) saveImageOfViewToPNGNamed:(NSString*)fileNameMinusExtension usingBackgroundColor:(UIColor*)backgroundColorOrNil;

@end


@implementation UIView (UIView_Snapshots)

- (UIImage*) imageOfViewUsingBackgroundColor:(UIColor*)backgroundColorOrNil
{
    // Opaque is faster
    BOOL opaqueCanvas = (backgroundColorOrNil) || (self.opaque && self.layer.cornerRadius == 0);
    
    // Creeate a canvas
    UIGraphicsBeginImageContextWithOptions(self.bounds.size, opaqueCanvas, 0.0);
    
    // If we have a background collor begin by fillling the canvas
    if (backgroundColorOrNil) 
    {
      CGContextRef context = UIGraphicsGetCurrentContext();
      CGContextSetFillColorWithColor(context, backgroundColorOrNil.CGColor);
      CGContextFillRect(context, self.bounds);
    }
    
    // Render the view on the canvas
    [self.layer renderInContext:UIGraphicsGetCurrentContext()];
    
    // Return the image repsrenstation of the canvas 
    UIImage* img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return img;
}

- (void) saveImageOfViewToPNGNamed:(NSString*)fileNameMinusExtension usingBackgroundColor:(UIColor*)backgroundColorOrNil
{
    // Create the path
    NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString* documentsDirectory = [paths objectAtIndex:0];
    NSString* destPath = [documentsDirectory stringByAppendingPathComponent:fileNameMinusExtension];
    destPath = [destPath stringByAppendingFormat:@".png"];
    
    // Create the image
    UIImage* image = [self imageOfViewUsingBackgroundColor:backgroundColorOrNil];
    
    // Save as a PNG
    [UIImagePNGRepresentation(image) writeToFile:destPath atomically:YES];
    
    // Write out the contents of home directory to console
    NSError *error;
    NSFileManager *fileMgr = [NSFileManager defaultManager];
    NSLog(@"Documents directory: %@", [fileMgr contentsOfDirectoryAtPath:documentsDirectory error:&error]);
}

@end

UIViewSnapshots.m

@interface UIView (UIView_Snapshots)

// Take image snapshots of the current state of a view.

// Use the background color of the superview if you have rounded corners
// If background color is nil the background will be treated as transparent
- (UIImage*) imageOfViewUsingBackgroundColor:(UIColor*)backgroundColorOrNil;

// Will save to the documents directory as XXXX.png
- (void) saveImageOfViewToPNGNamed:(NSString*)fileNameMinusExtension usingBackgroundColor:(UIColor*)backgroundColorOrNil;

@end


@implementation UIView (UIView_Snapshots)

- (UIImage*) imageOfViewUsingBackgroundColor:(UIColor*)backgroundColorOrNil
{
    // Opaque is faster
    BOOL opaqueCanvas = (backgroundColorOrNil) || (self.opaque && self.layer.cornerRadius == 0);
    
    // Creeate a canvas
    UIGraphicsBeginImageContextWithOptions(self.bounds.size, opaqueCanvas, 0.0);
    
    // If we have a background collor begin by fillling the canvas
    if (backgroundColorOrNil) 
    {
      CGContextRef context = UIGraphicsGetCurrentContext();
      CGContextSetFillColorWithColor(context, backgroundColorOrNil.CGColor);
      CGContextFillRect(context, self.bounds);
    }
    
    // Render the view on the canvas
    [self.layer renderInContext:UIGraphicsGetCurrentContext()];
    
    // Return the image repsrenstation of the canvas 
    UIImage* img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return img;
}

- (void) saveImageOfViewToPNGNamed:(NSString*)fileNameMinusExtension usingBackgroundColor:(UIColor*)backgroundColorOrNil
{
    // Create the path
    NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString* documentsDirectory = [paths objectAtIndex:0];
    NSString* destPath = [documentsDirectory stringByAppendingPathComponent:fileNameMinusExtension];
    destPath = [destPath stringByAppendingFormat:@".png"];
    
    // Create the image
    UIImage* image = [self imageOfViewUsingBackgroundColor:backgroundColorOrNil];
    
    // Save as a PNG
    [UIImagePNGRepresentation(image) writeToFile:destPath atomically:YES];
    
    // Write out the contents of home directory to console (Optional test)
    //NSError *error;
    //NSFileManager *fileMgr = [NSFileManager defaultManager];
    //NSLog(@"Documents directory: %@", [fileMgr contentsOfDirectoryAtPath:documentsDirectory error:&error]);
}

@end