How to create an image from a UIView / UIScrollView
I have an image in an UIScrollView, that can be scrolled and zoomed.
When the user presses a but开发者_运维技巧ton, I want the code to create an image from whatever part of the UIScrollView is inside an area I specify with a CGRect.
I've seen code to crop UIImages, but I can't adapt it to do the same for a view, because it uses CGContextDrawImage.
Any thoughts?
Cheers, Andre
I've managed to get it.
Here's my solution, based on a few different ones from the web:
- (UIImage *)imageByCropping:(UIScrollView *)imageToCrop toRect:(CGRect)rect
{
CGSize pageSize = rect.size;
UIGraphicsBeginImageContext(pageSize);
CGContextRef resizedContext = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(resizedContext, -imageToCrop.contentOffset.x, -imageToCrop.contentOffset.y);
[imageToCrop.layer renderInContext:resizedContext];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
which you call by using:
CGRect clippedRect = CGRectMake(0, 0, 320, 300);
picture.image = [self imageByCropping:myScrollView toRect:clippedRect];
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