Question

我想知道如何保存以下类中的对象数组：

class CustomDocument: NSObject, NSCoding {
    let name : String
    let image : UIImage

    init(n: String, i: UIImage){
        name = n
        image = i
    }

    //other code excluded
}

最初，我将此数组保存为“用户默认设置”。由于对象占用了大量空间，因此在应用程序中造成了很多滞后。

保存占用大量空间的数据数组的最佳方法是什么？

非常感谢您的帮助，感谢您的答复。

Answer 1

尝试以下代码，希望对您有所帮助：

<div style="">
        <div style="outline: none;">
            <input class="item" type="checkbox" style="outline: none; margin-left: 0px; margin-right: 6px;" id="InsertRecordCheckList_3a4dfdb26cc834_checked_0">
            <label for="InsertRecordCheckList_3a4dfdb26cc834_checked_0">Apple</label>
        </div>
        <div  style="outline: none;">
        <input class="item" type="checkbox" style="outline: none; margin-left: 0px; margin-right: 6px;" id="InsertRecordCheckList_3a4dfdb26cc834_checked_1">
        <label for="InsertRecordCheckList_3a4dfdb26cc834_checked_1">Banana</label>
        </div>
        <div style="outline: none;">
        <input class="item" type="checkbox" style="outline: none; margin-left: 0px; margin-right: 6px;" id="InsertRecordCheckList_3a4dfdb26cc834_checked_2">
        <label for="InsertRecordCheckList_3a4dfdb26cc834_checked_2">Melon</label>
        </div>
        <div style="outline: none;">
        <input class="item" type="checkbox" style="outline: none; margin-left: 0px; margin-right: 6px;" id="InsertRecordCheckList_3a4dfdb26cc834_checked_3">
        <label for="InsertRecordCheckList_3a4dfdb26cc834_checked_3">Mango</label>
        </div>
        <div style="outline: none;">
        <input class="item" type="checkbox" style="outline: none; margin-left: 0px; margin-right: 6px;" id="InsertRecordCheckList_3a4dfdb26cc834_checked_4">
        <label for="InsertRecordCheckList_3a4dfdb26cc834_checked_4">Grapes</label>
        </div>
        <div style="outline: none;">
        <input class="item" type="checkbox" style="outline: none; margin-left: 0px; margin-right: 6px;" id="InsertRecordCheckList_3a4dfdb26cc834_checked_5">
        <label for="InsertRecordCheckList_3a4dfdb26cc834_checked_5">Peach</label>
        </div>
      </div>

示例：

class CustomDocument: NSObject, NSCoding  {

    var name : String?
    var image : UIImage?

    func encode(with aCoder: NSCoder) {
        aCoder.encode(name, forKey: "namekey")
        if let imageData = image!.jpegData(compressionQuality: 1.0){
            aCoder.encode(imageData, forKey: "imagekey")
        }
        UserDefaults.standard.synchronize()
    }

    required convenience init?(coder aDecoder: NSCoder) {
        self.init()
        if let name =  (aDecoder.decodeObject(forKey: "namekey") as? String){
            self.name = name
        }
        if let imageData = (aDecoder.decodeObject(forKey: "imagekey")  as? Data){
            if let image = UIImage(data: imageData){
                self.image = image
            }
        }
    }
}


func archiveDocument(document:CustomDocument) -> Data? {
    do {
        let archivedObject = try NSKeyedArchiver.archivedData(withRootObject: document, requiringSecureCoding: false)
        return archivedObject

    } catch {
        // do something with the error
    }
    return nil
}


func unarchiveDocument(unarchivedObject:Data) -> CustomDocument? {
    do {
        if let document = try NSKeyedUnarchiver.unarchiveTopLevelObjectWithData(unarchivedObject) as? CustomDocument {
            return document
        }
    } catch {
        // do something with the error
    }
    return nil
}

如何在Swift和Xcode中保存对象数组（带有图像变量）？

1 个答案: