使用nsuserdefaults保存图像数组 [英] Saving an image array with nsuserdefaults

问题描述

我有一个用户拍照的应用程序，一旦拍照，它就在某个 UICollectionView 中。我一直收到这个错误：

I have an app where the user takes a picture and once the picture is taken it is in a certain UICollectionView. I keep getting this error:

"cannot invoke 'setObject' with an argument list of type '(UIImage. type, forKey:[UIImage])'"

我在这里搜索了文档和帖子，但没有任何帮助。
这是我的代码。 （注意：我只在一个案例中做过，原因很明显）

I've searched through documentation and posts on here, but nothing helps. This is my code. (note: I only did it in one case, for obvious reasons)

//userdefualts
let defualts = NSUserDefaults.standardUserDefaults()

func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [NSObject : AnyObject]) {

    picker.dismissViewControllerAnimated(true, completion: nil)

    switch currentClothesSelection!{

        case "1":
            shirts.append(info[UIImagePickerControllerOriginalImage] as! UIImage)

            //this is where the error occurs
            defualts.setObject(UIImage.self, forKey: array1)

        case "2" :
            pants.append(info[UIImagePickerControllerOriginalImage] as! UIImage)
        case "3" :
            shorts.append(info[UIImagePickerControllerOriginalImage] as! UIImage)
        case "4" :
            jackets.append(info[UIImagePickerControllerOriginalImage] as! UIImage)
        case "5" :
            shoes.append(info[UIImagePickerControllerOriginalImage] as! UIImage)

        default:
         break
    }

请帮忙。在此先感谢。

推荐答案

编辑/更新：

Xcode 8 beta•Swift 3

在NSUserDefaults存储图像不是一个好主意，但如果你真的想这样做，你需要存储是as NSData。

It is not a good idea to store images at NSUserDefaults but if you really want to do it you need to store is as NSData.

value参数只能是属性列表对象：NSData，
NSString，NSNumber，NSDate，NSArray或的NSDictionary。对于NSArray和NSDictionary对象，它们的内容必须是属性列表对象

The value parameter can be only property list objects: NSData, NSString, NSNumber, NSDate, NSArray, or NSDictionary. For NSArray and NSDictionary objects, their contents must be property list objects

我建议将它本地保存到Documents文件夹中的磁盘。如果你真的想把它保存到NSUserDefaults，我建议只使用小图片并自行承担风险:)你可以这样做：

I recommend saving it locally to disk at the Documents Folder. If you really want to save it to NSUserDefaults, I recommend using just for small images and do it at your own risk :) You can do as follow:

extension UserDefaults {
    func set(image: UIImage?, forKey key: String) {
        guard let image = image else {
            set(nil, forKey: key)
            return
        }
        set(UIImageJPEGRepresentation(image, 1.0), forKey: key)
    }
    func image(forKey key:String) -> UIImage? {
        guard let data = data(forKey: key), image = UIImage(data: data )
            else  { return nil }
        return image
    }
    func set(imageArray value: [UIImage]?, forKey key: String) {
        guard let value = value else {
            set(nil, forKey: key)
            return
        }
        set(NSKeyedArchiver.archivedData(withRootObject: value), forKey: key)
    }
    func imageArray(forKey key:String) -> [UIImage]? {
        guard  let data = data(forKey: key),
            imageArray = NSKeyedUnarchiver.unarchiveObject(with: data) as? [UIImage]
            else { return nil }
        return imageArray
    }
}

测试：

let myImage = UIImage(data: try! Data(contentsOf: URL(string:"https://i.stack.imgur.com/Xs4RX.jpg")!))!
UserDefaults.standard().set(image: myImage, forKey: "anyKey")
if let myLoadedImage = UserDefaults.standard().image(forKey:"anyKey") {
    print(myLoadedImage.size)  // "(719.0, 808.0)"
}

let myImagesArray = [myImage, myImage]
UserDefaults.standard().set(imageArray: myImagesArray, forKey: "imageArrayKey")
if let myLoadedImages = UserDefaults.standard().imageArray(forKey:"imageArrayKey") {
    print(myLoadedImages.count)  // 2
}

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