ios - Swift - prepareforsegue 值未传递到所需的 init

Question

Array 类型的值应该通过 ViewController1 中的 prepareForSegue 传递到 forceView2 和 stiffView2。但是，当我在 ViewController2 中打印时，forceView2 和 stiffView2 都是空的。

谁能解释为什么它在 required init 中时不起作用？

ViewController1

@IBAction func solve_Pressed(sender: AnyObject) {

        self.performSegueWithIdentifier("Solve", sender: sender)

    }

 override func prepareForSegue ( segue: UIStoryboardSegue, sender: AnyObject!) {

        if (segue.identifier == "Solve") {
            var svcViewController2 = segue.destinationViewController as springViewController2

            svcViewController2.forceView2 = self.force
            svcViewController2.stiffView2 = self.stiffness
        }

ViewController2

var forceView2 = [Float]()
var stiffView2 = [Float]()
var forceB1 : Float
var forceB2 : Float
var SpringD : [Float]

required init (coder aDecoder: NSCoder) {

    if(isCheckedGlobal) {
    (forceB1,forceB2,SpringD) = calculateBoundary(&forceView2, stiffView2, springNum) }

else {  println(forceView2)
        println(stiffView2)
        println(springNum)

        SpringD = calculate(forceView2, stiffView2, springNum)
        self.forceB1  = forceView2[0]
        self.forceB2 = 0.0
 }

Answer 1

初始化在您实例化 viewController 时完成，在这一行:var svcViewController2 = segue.destinationViewController as springViewController2。此时您的值尚未通过。

例如，您应该尝试在viewDidLoad 方法中println() 您的数据。

编辑:

我现在不能尝试，但你应该尝试这样的事情:

var forceView2 = [Float]()
var stiffView2 = [Float]()
var forceB1 : Float
var forceB2 : Float
var SpringD : [Float]

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

override func viewDidLoad() {
    super.viewDidLoad()

    if(isCheckedGlobal) {
        (forceB1,forceB2,SpringD) = calculateBoundary(&forceView2, stiffView2, springNum) }

    else {
        println(forceView2)
        println(stiffView2)
        println(springNum)

        SpringD = calculate(forceView2, stiffView2, springNum)
        self.forceB1  = forceView2[0]
        self.forceB2 = 0.0
    }
}

如果需要，请不要忘记检查您的属性(可选、无、...)。