如何解決UITableViewController指定的初始化錯誤？

Question

我是swift新手，在PlacesTableViewController類中聲明我的初始化器時出現問題。它提示我，當我加入Super.init，它會提示我「Super.init不是從初始化返回之前被稱爲」：

"Must call a designated initializer of the superclass 'UITableViewController'"

這是我的PlacesTableViewController.swift文件：

class PlacesTableViewController: UITableViewController { 

    var pa55DB : COpaquePointer = nil 
    var selectStatement : COpaquePointer = nil; 

    var chapterdata : Array<Entry> = [] 
    var ety : Entry 
    var sqlString : String = ""; 

    var chpData : ChapterData 

    init(pa55DB : COpaquePointer,selectStatement : COpaquePointer, chapterdata : Array<Entry>, ety : Entry, sqlString : String) { 
     super.init() 
     self.pa55DB = pa55DB 
     self.selectStatement = selectStatement 
     self.chapterdata = chapterdata 
     self.ety = ety 
     self.sqlString = sqlString 

    } 

    required init!(coder aDecoder: NSCoder!) { 
     fatalError("init(coder:) has not been implemented") 
    } 


    override func viewDidLoad() { 
     super.viewDidLoad() 

     chpData = ChapterData(newEntryArray : chapterdata, entryV : ety, paDB55 : pa55DB, selectStatement : selectStatement, sqlString : sqlString) 
     chpData.openDB() 
     chapterdata = chpData.prepareStartment() 

     println("Testing...") 
    } 
... 
} 

這裏是我叫ChapterData.swift另一個類文件，用來打開數據庫和檢索數據

class Entry { 

    let image : String! 
    let heading : String! 
    let title : String! 
    let description : String! 
    public init(image : String, heading : String, title : String, desc : String) { 
     self.heading = heading 
     self.image = image 
     self.title = title 
     self.description = desc 
    } 
} 


class ChapterData { 

    var paDB : COpaquePointer = nil; 
    var selectStatement : COpaquePointer = nil; 
    var sqlString : String = ""; 

    var newEntryArray : Array<Entry> = []; 
    var entryV : Entry; 

    init(newEntryArray : Array<Entry>, entryV : Entry, paDB55 : COpaquePointer, selectStatement : COpaquePointer, sqlString : String){ 
     self.newEntryArray = newEntryArray 
     self.entryV = entryV 
     self.paDB = paDB55 
     self.selectStatement = selectStatement 
     self.sqlString = sqlString 
    } 

    func openDB() { 
     var paths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] as! String 
     var docsDir = paths.stringByAppendingPathComponent("pa55.sqlite") 


     if (sqlite3_open(docsDir, &paDB) == SQLITE_OK) { 
      println("success open database") 
     } 
     else { 
      println("failed to open database") 
     } 
    } 

    func prepareStartment() -> Array<Entry> { 
     sqlString = "SELECT * FROM Chapter ORDER BY CID ASC" 
     var cSql = sqlString.cStringUsingEncoding(NSUTF8StringEncoding) 
     sqlite3_prepare_v2(paDB, cSql!, -1, &selectStatement, nil) 

     println("startment start") 

     while (sqlite3_step(selectStatement) == SQLITE_ROW) { 

      let image_buf = sqlite3_column_text(selectStatement, 3) 
      var image = String.fromCString(UnsafePointer<CChar>(image_buf)) 

      let heading_buf = sqlite3_column_text(selectStatement, 1) 
      var heading = String.fromCString(UnsafePointer<CChar>(heading_buf)) 

      let title_buf = sqlite3_column_text(selectStatement, 2) 
      var title = String.fromCString(UnsafePointer<CChar>(title_buf)) 

      let desc_buf = sqlite3_column_text(selectStatement, 4) 
      var description = String.fromCString(UnsafePointer<CChar>(desc_buf)) 

      entryV = Entry(image: image!, heading: heading!, title: title!, desc: description!) 
      newEntryArray.append(entryV) 
     } 
     println("select statement successful executed") 
     return newEntryArray 
    } 

} 

Answer 1

查看這是否解決您的問題：

override init(style: UITableViewStyle) { 
    super.init(style: style) 
} 

init(pa55DB : COpaquePointer,selectStatement : COpaquePointer, chapterdata : Array<Entry>, ety : Entry, sqlString : String) { 
    super.init(style: UITableViewStyle.Plain) 
    self.pa55DB = pa55DB 
    self.selectStatement = selectStatement 
    self.chapterdata = chapterdata 
    self.ety = ety 
    self.sqlString = sqlString 

} 

UITableView Class Reference

從斯威夫特編程語言指南：

Designated initializers are the primary initializers for a class. A designated initializer fully initializes all properties introduced by that class and calls an appropriate superclass initializer to continue the initialization process up the superclass chain.

[read more]

---

更新：

上面的代碼實際上解決了您的指定初始化程序的問題。您現在需要正確初始化您的self.ety屬性。

Answer 2

init mess是ObjC的一個已知限制< - > Swift橋接。

解決此問題的一種方法是委託給super的init(nibName:bundle:)初始值設定項。

class PlacesTableViewController: UITableViewController { 

    var chapterdata: [Entry] 
    var chpData: ChapterData? 
    var ety: Entry 
    var pa55DB: COpaquePointer 
    var selectStatement: COpaquePointer 
    var sqlString: String 


    init(pa55DB: COpaquePointer, selectStatement: COpaquePointer, chapterdata: [Entry], ety: Entry, sqlString: String) { 
     self.pa55DB = pa55DB 
     self.selectStatement = selectStatement 
     self.chapterdata = chapterdata 
     self.ety = ety 
     self.sqlString = sqlString 

     super.init(nibName: nil, bundle: nil) 
    } 


    required init(coder: NSCoder) { 
     fatalError("init(coder:) has not been implemented") 
    } 

    // … 
} 

Answer 3

也許嘗試這樣的事：

class PlacesTableViewController: UITableViewController { 

    var chapterdata: [Entry] 
    var chpData: ChapterData? 
    var ety: Entry 
    var pa55DB: COpaquePointer 
    var selectStatement: COpaquePointer 
    var sqlString: String 


    convenience init(pa55DB: COpaquePointer, selectStatement: COpaquePointer, chapterdata: [Entry], ety: Entry, sqlString: String) { 
     self.init() 

     self.pa55DB = pa55DB 
     self.selectStatement = selectStatement 
     self.chapterdata = chapterdata 
     self.ety = ety 
     self.sqlString = sqlString 

    } 

    required init(coder aDecoder: NSCoder) { 
     super.init(coder: aDecoder) 
    } 

    // … 
} 

Answer 4

的UITableViewController不是什麼好東西了先進的用例。您可以隨時繼承UIViewController，把一個UITableView財產它，就像這樣：

class PlacesTableViewController: UIViewController { 

    let tableView = UITableView(frame: CGRectZero, style: .Plain) 

    override func loadView() { 
     view = tableView 
    } 

    // Custom designated initializer 
    init(pa55DB : COpaquePointer,selectStatement : COpaquePointer, chapterdata : Array<Entry>, ety : Entry, sqlString : String) { 
     // setting up these properties 
     super.init(nibName: nil, bundle: nil) // designated initializer of the superclass 'UIViewController'" 
    } 
} 

而且它就像UITableViewController。

其他公用事業UITableViewController提供，像refreshControl你也可以設置一個自己，像clearsSelectionOnViewWillAppear機制也可以在viewWillAppear()或didSelectRowAtIndexPath根據您的需要來實現。