ios - 为多个 ViewController 未 100% 工作的 segue 问题做准备

Question

有 4 个 View Controller :raceViewControllerraceInfoViewController能力CalcViewController能力最终 View Controller

快速概览该应用的工作原理。首先，用户在 abilityCalcViewController 中启动他们更新他们的统计数据，然后在完成后单击选择比赛按钮，然后转到 raceViewController。这里有 2 个按钮，一个指向 raceInfoViewController，另一个指向 abilityFinalViewController。每个不同的将有自己的一组信息在 ViewController 之间传递。

我的代码是:

override func prepare(for segue: UIStoryboardSegue, sender: Any?)
    {
        if segue.identifier == "abilityFinalViewController"
        {
            let destFinalViewController: abilityFinalViewController = segue.destination as! abilityFinalViewController

            destFinalViewController.strStatScore = strStatScore
        }
        else if segue.identifier == "raceInfoViewController"
        {
            let destViewController: raceInfoViewController = segue.destination as! raceInfoViewController
            // Dwarf
            if raceTable.indexPathForSelectedRow == [0,0]
            {
                print(raceTable.indexPathForSelectedRow ?? 0)
                destViewController.raceName = races[0]
                destViewController.raceStat = stats[0]
            }

            // Elf
            else if raceTable.indexPathForSelectedRow == [0,1]
            {
                destViewController.raceName = races[1]
                destViewController.raceStat = stats[1]
            }

            // Gnome
            else if raceTable.indexPathForSelectedRow == [0,2]
            {
                destViewController.raceName = races[2]
                destViewController.raceStat = stats[2]
            }

            // Half Elf
            else if raceTable.indexPathForSelectedRow == [0,3]
            {
                destViewController.raceName = races[3]
                destViewController.raceStat = stats[3]
            }

            // Half-Orc
            else if raceTable.indexPathForSelectedRow == [0,4]
            {
                destViewController.raceName = races[4]
                destViewController.raceStat = stats[4]
            }

            // Halfling
            else if raceTable.indexPathForSelectedRow == [0,5]
            {
                destViewController.raceName = races[5]
                destViewController.raceStat = stats[5]
            }

            // Human
            else if raceTable.indexPathForSelectedRow == [0,6]
            {
                destViewController.raceName = races[6]
                destViewController.raceStat = stats[6]
            }

            // Ifrit
            else if raceTable.indexPathForSelectedRow == [0,7]
            {
                destViewController.raceName = races[7]
                destViewController.raceStat = stats[7]
            }

            // Oread
            else if raceTable.indexPathForSelectedRow == [0,8]
            {
                destViewController.raceName = races[8]
                destViewController.raceStat = stats[8]
            }

            // Sylph
            else if raceTable.indexPathForSelectedRow == [0,9]
            {
                destViewController.raceName = races[9]
                destViewController.raceStat = stats[9]
            }

            // Tengu
            else if raceTable.indexPathForSelectedRow == [0,10]
            {
                destViewController.raceName = races[10]
                destViewController.raceStat = stats[10]
            }

            // Undine
            else if raceTable.indexPathForSelectedRow == [0,11]
            {
                destViewController.raceName = races[11]
                destViewController.raceStat = stats[11]
            }
        }
    }

我的问题是，当我单击指向 abilityFinalViewController 的按钮或指向 raceInfoViewController 的按钮时，它会进行转换，但随后不会传递任何数据。所以 destFinalViewController.strStatScore = strStatScore 在到达下一个目的地时似乎是空白的。我错过了什么？

Answer 1

请注意，根据 segue 标识符决定要做什么的 prepareForSegue 代码是脆弱的。如果您忘记设置标识符，或者标识符中有拼写错误，它将不起作用。

在 Swift 中，我更喜欢使用基于目标 View Controller 的类进行切换的 switch 语句:

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    switch segue.destinationViewController {

    case let miniCarContainerViewController as MiniCartConatinerViewController:
        //Code to configure MiniCartConatinerViewController
        print("Destination is class MiniCartConatinerViewController")

    case let addOnsItemViewController as AddonsItemViewController:
        //Code to configure AddonsItemViewController
        print("Destination is class MiniCartConatinerViewController")

    default:
        print("Destination is unknown class!")
        break
    }
}

case let 语法有双重职责，因为它可以根据目标 View Controller 的类将局部变量转换为正确的类型。

顺便说一下，类名和类型名在 Swift 中应该总是以大写字母开头。变量名应以小写字母开头。因此，您的 abilityFinalViewController 类应命名为 AbilityFinalViewController，raceInfoViewController 应命名为 RaceInfoViewController。