使用 Swift 将输入从 TextField 打印到 Xcode 中的标签

Printing input from TextField to a Label in Xcode with Swift

提问by Dylan Bailey

I'm working on a simple guessing game app, just to get more comfortable with Swift and Xcode. I have been able to input within userInput and get it to print a message to the console, however when I try to get it to print my input to usersGuess(which is a label), I can not figure it out.

我正在开发一个简单的猜谜游戏应用程序，只是为了更好地使用 Swift 和 Xcode。我已经能够在 userInput 中输入并让它向控制台打印一条消息，但是当我尝试让它将我的输入打印到 usersGuess（这是一个标签）时，我无法弄清楚。

Here's my code within a single view application via Xcode:

这是我通过 Xcode 在单个视图应用程序中的代码：

import UIKit

class ViewController: UIViewController {
    @IBOutlet weak var correctAnswerLabel: UILabel!
    @IBOutlet weak var usersGuess: UILabel!

    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 buttonPressed() {
        correctAnswerLabel.text = "Changes when the button is pressed."
    }

    @IBAction func userInput(sender: UITextField) {
        println("This is working")
    }


}

I'm sure this is simple, but I am scratching my head lol.

我确定这很简单，但我正在挠头哈哈。

回答by mbo42

@IBAction func userInput(sender: UITextField) {
    println("This is working")
    usersGuess.text = sender.text
}

回答by erichoco

Although I am still new to iOS dev and Swift, I think you could also take a look at the use of delegate in this tutorialApple provides. I guess it might be the code didn't resign your text field's first-responder status. Hence, the usersGuesscould not update. (Anyone who knows how this work please leave a comment.)

虽然我对 iOS 开发和 Swift 还是个新手，但我想你也可以看看Apple 提供的本教程中委托的使用。我想这可能是代码没有放弃您的文本字段的第一响应者状态。因此，usersGuess无法更新。（谁知道这是如何工作的，请发表评论。）

To do this, basically

要做到这一点，基本上

• Create an outlet for the UITextFieldthat receives user's input, say, usersInput.
• Set ViewControlleras a delegate of usersInput, which will
• Resign the first-responder status of usersInputwhen the Return button on the keyboard is pressed.
• Update the text of usersGuess.

• 创建一个用于UITextField接收用户输入的插座，例如，usersInput。
• 设置ViewController为 的代表usersInput，这将
• usersInput当按下键盘上的返回按钮时，放弃第一响应者状态。
• 更新 的文本usersGuess。

Code here:

代码在这里：

import UIKit

class ViewController: UIViewController, UITextFieldDelegate {
    @IBOutlet weak var correctAnswerLabel: UILabel!
    @IBOutlet weak var usersGuess: UILabel!
    @IBOutlet weak var usersInput: UITextField!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        // Set ViewController as a delegate
        usersInput.delegate = self
    }

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

    // Here are the callback functions for usersInput
    func textFieldShouldReturn(textField: UITextField) -> Bool {
        textField.resignFirstResponder()
        return true
    }

    func textFieldDidEndEditing(textField: UITextField) {
        usersGuess.text = textField.text
    }

    @IBAction func buttonPressed() {
        correctAnswerLabel.text = "Changes when the button is pressed."
    }

    @IBAction func userInput(sender: UITextField) {
        println("This is working")
    }

}