将UIColor保存到NSUserDefaults并从NSUserDefaults加载 [英] Saving UIColor to and loading from NSUserDefaults

问题描述

将 UIColor 保存到 NSUserDefaults 然后将其恢复出来最简单的方法是什么？

What's the easiest way to save a UIColor into NSUserDefaults and then get it back out?

推荐答案

通过接受的答案，你很快会得到很多NSKeyed档案&取消归档所有的代码。一个更清洁的解决方案是扩展NSUserDefaults。这正是扩展是什么; NSUserDefaults可能不知道UIColor，因为它是因为UIKit和Foundation是不同的框架。

With the accepted answer, you'll quickly end up with a lot of NSKeyed archives & unarchives all over your code. A cleaner solution is to extend NSUserDefaults. This is exactly what extensions are for; NSUserDefaults probably doesn't know about UIColor as it is because UIKit and Foundation are different frameworks.

extension NSUserDefaults {

    func colorForKey(key: String) -> UIColor? {
        var color: UIColor?
        if let colorData = dataForKey(key) {
            color = NSKeyedUnarchiver.unarchiveObjectWithData(colorData) as? UIColor
        }
        return color
    }

    func setColor(color: UIColor?, forKey key: String) {
        var colorData: NSData?
        if let color = color {
            colorData = NSKeyedArchiver.archivedDataWithRootObject(color)
        }
        setObject(colorData, forKey: key)
    }

}

使用

Usage

NSUserDefaults.standardUserDefaults().setColor(UIColor.whiteColor(), forKey: "white")
let whiteColor = NSUserDefaults.standardUserDefaults().colorForKey("white")

这也可以在具有类别的Objective-C中完成。

This can also be done in Objective-C with a category.

我已将此处添加为Swift文档。

I've added the Swift file as a gist here.

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