ios - Swift: self.init (coder : aDecoder) 使用 EXC_BAD_ACCESS 导致应用程序崩溃

Question

错误是使用 NSCoder 和 NSKeyArchiver 时应用崩溃。

我最近发表了一篇关于 NSCoder 的文章，但从那以后我更改了我的代码并遇到了一个新错误，因此我决定最好还是写一篇新文章。

该应用程序是一个博客阅读器，使用 PHP 从 MYSQL 数据库读取数据，并使用 JSON 在 Swift 中使用自定义对象填充表格 View 。我一直在尝试保存 mainArray，以便当用户跨部分移动单元格(每个部分都有一个数组)时，它可以保存用户离开它的位置。

Blog.swift:处理博客自定义对象

import UIKit

class Blog: NSObject, NSCoding {

var blogName: String!
var blogStatus1: String!
var blogStatus2: String!
var blogURL: String!
var blogID: String!
var blogType: String!
var blogDate: String!
var blogPop: String!

static func createBlog(from jsonObject: AnyObject) -> Blog? {

    guard let bID: String = jsonObject.object(forKey: "id") as? String,
        let bName: String = jsonObject.object(forKey: "blogName") as? String,
        let bStatus1: String = jsonObject.object(forKey: "blogStatus1") as? String,
        let bStatus2: String = jsonObject.object(forKey: "blogStatus2") as? String,
        let bURL: String = jsonObject.object(forKey: "blogURL") as? String,
        let bType: String = jsonObject.object(forKey: "blogType") as? String,
        let bDate: String = jsonObject.object(forKey: "blogDate") as? String,
        let bPop: String = jsonObject.object(forKey: "blogPop") as? String

        else {
          print("Error: (Creating Blog Object)")
          return nil
 }

let blog = Blog()
    blog.blogName = bName
    blog.blogStatus1 = bStatus1
    blog.blogStatus2 = bStatus2
    blog.blogURL = bURL
    blog.blogID = bID
    blog.blogType = bType
    blog.blogDate = bDate
    blog.blogPop = bPop
    return blog
 }

// NSCoding
convenience required init?(coder aDecoder: NSCoder) {
    self.init (coder : aDecoder) // *** Crashes Here ***
    self.blogName = aDecoder.decodeObject(forKey: "blogName") as! String
    self.blogStatus1 = aDecoder.decodeObject(forKey: "blogStatus1") as! String
    self.blogStatus2 = aDecoder.decodeObject(forKey: "blogStatus2") as! String
    self.blogURL = aDecoder.decodeObject(forKey: "blogURL") as! String
    self.blogID = aDecoder.decodeObject(forKey: "blogID") as! String
    self.blogType = aDecoder.decodeObject(forKey: "blogType") as! String
    self.blogDate = aDecoder.decodeObject(forKey: "blogDate") as! String
    self.blogPop = aDecoder.decodeObject(forKey: "blogPop") as! String
 }

func encode(with aCoder: NSCoder) {
    aCoder.encode(blogName, forKey: "blogName")
    aCoder.encode(blogStatus1, forKey: "blogStatus1")
    aCoder.encode(blogStatus2, forKey: "blogStatus2")
    aCoder.encode(blogURL, forKey: "blogURL")
    aCoder.encode(blogID, forKey: "blogID")
    aCoder.encode(blogType, forKey: "blogType")
    aCoder.encode(blogDate, forKey: "blogDate")
    aCoder.encode(blogPop, forKey: "blogPop")
 }
}

MainController.swift - TableView 所在的位置

var mainArray = [Blog]()
var followedArray = [Blog]()

override func viewDidLoad() {
    super.viewDidLoad()

    // Receiving Data from Server
    retrieveData()

    if let data = UserDefaults.standard.data(forKey: "mainArrayKey"),
        let myBlogList = NSKeyedUnarchiver.unarchiveObject(with: data) as? [Blog] {
        mainArray = myBlogList
        print("mainArray: \(mainArray)")
    } else {
        print("Error: (Saving to UserDefaults)")
    }
}

// Retrieving Data from Server
func retrieveData() {

    let getDataURL = "http://example.com/receiving.php"
    let url: NSURL = NSURL(string: getDataURL)!

    do {
        let data: Data = try Data(contentsOf: url as URL)
        let jsonArray = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as! NSMutableArray

        // Looping through jsonArray
        for jsonObject in jsonArray {
            if let blog = Blog.createBlog(from: jsonObject as AnyObject) {
                mainArray.append(blog)

                // Save to UserDefaults
                let encodedData = NSKeyedArchiver.archivedData(withRootObject: mainArray)
                UserDefaults.standard.set(encodedData, forKey: "mainArrayKey")
            }
        }
    }
    catch {
        print("Error: (Retrieving Data)")
    }
    myTableView.reloadData()

    // Logs
    print("This is mainArray", mainArray)

    // Check UserDefaults
    if UserDefaults.standard.object(forKey: "mainArrayKey") != nil{
        print("mainArray key exists")
    }
    else {
        print("mainArray key does not exist")
    }
}

Answer 1

在我看来就像一个无限循环。你调用init(coder:)，第一行调用init(coder:)，第一行调用init(coder:) , 依此类推。

您需要在其中调用不同的初始化程序。请改用 self.init()。