How Can Take a Screen Shot of a UIView ?

How to take screen shot of UIVIew In iOS Development 

iOS 7 has a new method that allows you to draw a view hierarchy into the current graphics context. This can be used to get an UIImage very fast.

I implemented a category method on UIView to get the view as an UIImage:

- (UIImage *)pb_takeSnapshot {
    UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, NO, [UIScreen mainScreen].scale);

    [self.view drawViewHierarchyInRect:self.view.bounds afterScreenUpdates:YES];

    // old style [self.view.layer renderInContext:UIGraphicsGetCurrentContext()];

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

It is considerably faster then the existing renderInContext: method.

Reference : https://developer.apple.com/library/ios/qa/qa1817/_index.html

If I have a view (testView) that is 400x320 and I need to take a screenshot of part of this view (say rect = (50, 50, 200, 200)).

After getting the whole snapshot, you could draw it in a smaller Graphic Context in a way that you get the part you want:




UIGraphicsBeginImageContextWithOptions(CGSizeMake(200, 200), NO, [UIScreen mainScreen].scale);
[self.testView drawViewHierarchyInRect:CGRectMake(-50, -50, self.testView.bounds.size.width, self.testView.bounds.size.height) afterScreenUpdates:YES];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();