Question

我对这一切都很陌生，我找到了一些让我理解这种语法的代码。我正在尝试创建一个文本字段，让我输入一个更新步进器值的值。步进器当前工作（更新uitextfield），但是当我更改文本字段中的值时，它不会更新步进器的值，所以当我单击步进器时，它会恢复到我输入值之前的任何值。 ..谁能告诉我为什么STracksValueDidChange和CTrackValueDidChange这两个函数都有错误？

到目前为止，这是我的代码：

import UIKit

类ViewController：UIViewController {

@IBOutlet weak var STracks: UITextField!
@IBOutlet weak var STracksStepper: UIStepper!
@IBOutlet weak var CTracks: UITextField!
@IBOutlet weak var CTrackStepper: UIStepper!



override func viewDidLoad() {
    super.viewDidLoad()


    STracksStepper.autorepeat = true
    STracksStepper.maximumValue = 100.0
    STracksStepper.minimumValue = 2.0
    STracksStepper.stepValue = 2.0
    print(STracksStepper.value)
    STracks.text = "\(Int(STracksStepper.value))"
    STracksStepper.addTarget(self, action: "SstepperValueDidChange:", forControlEvents: .ValueChanged)
    STracks.addTarget(self, action: "STextValueDidChange:", forControlEvents: .ValueChanged)


    CTrackStepper.autorepeat = true
    CTrackStepper.maximumValue = 100.0
    CTrackStepper.minimumValue = 2.0
    CTrackStepper.stepValue = 2.0
    print(CTrackStepper.value)
    CTracks.text = "\(Int(CTrackStepper.value))"
    CTrackStepper.addTarget(self, action: "CstepperValueDidChange:", forControlEvents: .ValueChanged)
    CTracks.addTarget(self, action: "CTextValueDidChange:", forControlEvents: .ValueChanged)

}

//Steppers will update UITextFields
func SstepperValueDidChange(stepper: UIStepper) {

    let stepperMapping: [UIStepper: UITextField] = [STracksStepper: STracks]

    stepperMapping[stepper]!.text = "\(Int(stepper.value))"
}

func STracksValueDidChange(SText: UITextField) {

    let STextMapping: [UITextField: UIStepper] = [STracks: STracksStepper]

    STextMapping[SText]!.value = "(SText.text)"
}


func CstepperValueDidChange(stepper: UIStepper) {

    let stepperMapping: [UIStepper: UITextField] = [CTrackStepper: CTracks]

    stepperMapping[stepper]!.text = "\(Int(stepper.value))"
}


func CTrackValueDidChange(CText: UITextField) {

    let CTextMapping: [UITextField: UIStepper] = [CTracks: CTrackStepper]

    CTextMapping[CText]!.value = "(CText.text)"
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

}

Answer 1

尝试这样的事情。

CTrackStepper.value = Double(Textfield.text)

我不太确定您的代码中的映射是什么但我认为你不需要它来改变价值。

更新，自己做了一个项目：

 import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var textfield: UITextField!
    @IBOutlet weak var stepper: UIStepper!


    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


    @IBAction func stepperValueChanged(sender: UIStepper) {
        textfield.text = String(sender.value)
    }

    @IBAction func valueChanged(sender: UITextField) {
        if Double(sender.text!) != nil {
            stepper.value = Double(sender.text!)!
        }
    }
}

对于steppervaluechanged和valuechanged，只需从uistepper和textfield拖动并选择action并将Anyobject更改为Uitextfield的Uistepper。

祝你好运：）

从UITextField更改后，如何更改UIStepper值？

1 个答案: