Swift:设置单元格文本标签时无法摆脱 "Optional"

Question

我花了相当多的时间试图解决这个问题，但我并不高兴。

我在我的 appDelegate 中创建了一个数组 (levelArrayName)，它由一个 sqlite 数据库填充:

class AppDelegate: UIResponder, UIApplicationDelegate {

var window: UIWindow?
var database:COpaquePointer = nil
var levelArray: [[Int]] = []
var levelArrayName: [[String]] = []

func checkdatabase(){
    //check is database exist at path.....
    var dirPaths:NSString

    dirPaths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)[0] as! NSString;

    let databasePath = dirPaths.stringByAppendingString("/rugby.sqlite")
    let dbpath = databasePath.cStringUsingEncoding(NSUTF8StringEncoding)

    let filemanager = NSFileManager.defaultManager()

    if (!filemanager.fileExistsAtPath(databasePath))
    {
        let fileForCopy = NSBundle.mainBundle().pathForResource("rugby",ofType:"sqlite")
        filemanager.copyItemAtPath(fileForCopy!, toPath:databasePath, error: nil)
    }

    let error = sqlite3_open(dbpath!, &database)
    if error != SQLITE_OK
    {
        println("error while opening");
        sqlite3_close(database);
    }

}


func getLevels() {
    var selectQuery="SELECT * FROM level"
    var stmt:COpaquePointer = nil
    var result = sqlite3_prepare_v2(database, selectQuery, -1, &stmt, nil);

    if result != SQLITE_OK
    {
        println("failed  \(sqlite3_errmsg(database))")
        println("failed  \(sqlite3_errcode(database))")
    }
    else
    {
        result = sqlite3_step(stmt)

        while result == SQLITE_ROW {

            var levelID = Int(sqlite3_column_int(stmt, 0))
            var attackID = Int(sqlite3_column_int(stmt, 2))
            var defenceID = Int(sqlite3_column_int(stmt, 2))
            var runs = Int(sqlite3_column_int(stmt, 3))
            var tries = Int(sqlite3_column_int(stmt, 4))
            var name_buf = sqlite3_column_text(stmt, 5)
            var name = String.fromCString(UnsafePointer<CChar>(name_buf))

            result = sqlite3_step(stmt)

            self.levelArray += [[levelID, attackID, defenceID, runs, tries]]
            self.levelArrayName += [["\(name)"]]
        }
    }

}

然后我在我的一个 tableviewcontroller 中使用这个数组来设置单元格标签:

import Foundation
import UIKit

let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate

class LevelsViewController: UITableViewController, UITableViewDelegate,     UITableViewDataSource {


var levelArrayName = appDelegate.levelArrayName

override func viewDidLoad() {
    super.viewDidLoad()



    self.tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "cell")
}

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
    return 1
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return appDelegate.levelArray.count
}

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    let cell = tableView.dequeueReusableCellWithIdentifier("LevelCell", forIndexPath: indexPath) as! UITableViewCell

    cell.textLabel?.text = levelArrayName[indexPath.row][0]

    return cell

    //return UITableViewCell()


}

但是，单元格标签在数组中的字符串之前显示“可选:”。

我试过打开 appDelegate.levelArrayName，但我似乎无法让它工作。

我确信我遗漏了一些简单的东西，但希望能指出正确的方向。

谢谢

Answer 1

你需要解包数组中索引处的元素

if let text = levelArrayName[indexPath.row][0] {
    cell.textLabel?.text = text
}