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iphone - What is the best way to create a shadow behind a UIImageView

I have a UIImageView that I want to add a shadow behind. I wish that apple had that as a property but they have to make lots of things hard for us programmers so I need to ask this question.

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There's a better and easier way to do this. UIImageView inherits from UIView so it has a layer property. You can access the layer's shadow properties and bam, you got a shadow.

If you have the UIImageView as an IBOutlet to a nib file, you can just implement the awakeFromNib e.g.

Objective-C

- (void)awakeFromNib {
    imageView.layer.shadowColor = [UIColor purpleColor].CGColor;
    imageView.layer.shadowOffset = CGSizeMake(0, 1);
    imageView.layer.shadowOpacity = 1;
    imageView.layer.shadowRadius = 1.0;
    imageView.clipsToBounds = NO;
}

Don't forget to #import "QuartzCore/CALayer.h"


For Swift, you can go about it multiple ways. Create a class extension, subclass, or an imageView instance. Whichever the way, the process is the same in modifying the layers shadow property.

Swift 3

override func awakeFromNib() {
    super.awakeFromNib()

    imageView.layer.shadowColor = UIColor.purple.cgColor
    imageView.layer.shadowOffset = CGSize(width: 0, height: 1)
    imageView.layer.shadowOpacity = 1
    imageView.layer.shadowRadius = 1.0
    imageView.clipsToBounds = false
}

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