问题描述

我有一个 UIImageView，我想在后面添加一个阴影.我希望苹果有这个属性，但他们不得不让我们程序员做很多事情，所以我需要问这个问题.

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.

推荐答案

有一种更好、更简单的方法可以做到这一点.UIImageView 继承自 UIView 所以它有一个 layer 属性.您可以访问图层的阴影属性和 bam，您得到了一个阴影.

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.

如果您将 UIImageView 作为 IBOutlet 指向 nib 文件，则只需实现 awakeFromNib例如

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;
}

别忘了#import "QuartzCore/CALayer.h"

对于 Swift，您可以采取多种方式.创建类扩展、子类或 imageView 实例.无论哪种方式，修改layers shadow属性的过程都是一样的.

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.

斯威夫特 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
}

这篇关于在 UIImageView 后面创建阴影的最佳方法是什么的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！