Create new UIImage by adding shadow to existing UIImage
- by Tom Irving
I've taken a look at this question: http://stackoverflow.com/questions/962827/uiimage-shadow
But the accepted answer didn't work for me.
What I'm trying to do is take a UIImage and add a shadow to it, then return a whole new UIImage, shadow and all.
This is what I'm trying:
- (UIImage*)imageWithShadow {
CGColorSpaceRef colourSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef shadowContext = CGBitmapContextCreate(NULL, self.size.width, self.size.height + 1, CGImageGetBitsPerComponent(self.CGImage), 0,
colourSpace, kCGImageAlphaPremultipliedLast);
CGColorSpaceRelease(colourSpace);
CGContextSetShadow(shadowContext, CGSizeMake(0, -1), 1);
CGContextDrawImage(shadowContext, CGRectMake(0, 0, self.size.width, self.size.height), self.CGImage);
CGImageRef shadowedCGImage = CGBitmapContextCreateImage(shadowContext);
CGContextRelease(shadowContext);
UIImage * shadowedImage = [UIImage imageWithCGImage:shadowedCGImage];
CGImageRelease(shadowedCGImage);
return shadowedImage;
}
The result is that I get exactly the same image as before I put it through this method.
I am doing this the correct way, or is there something obvious I'm missing?
