Question

我在uiAlertController中有一个文本字段，我想要检索内部的内容以构建一个对象。我写了以下代码：

let alertController = UIAlertController(title: "Ajouter une description", message: "De quoi sagit il ?", preferredStyle: UIAlertControllerStyle.alert)
                    alertController.addTextField { (textField : UITextField) -> Void in
                        textField.placeholder = "Description"
                        self.theDescription = textField.text!
                    }
                    let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default) { (result : UIAlertAction) -> Void in
                        self.createArtWithDescription(description: self.theDescription)
                    }

                    alertController.addAction(okAction)
                    self.present(alertController, animated: true, completion: nil)
                    //
                }

要构建我的对象，我有另一个函数“createArtWithDescription”，但在内部我无法检索uiAlertController文本字段的内容。谢谢提前

Answer 1

简短回答：

    let okAction = UIAlertAction(title: "OK", style: .default) { (result : UIAlertAction) -> () in
        self.theDescription = alertController.textFields?.first?.text
        self.createArtWithDescription(description: self.theDescription)
    }

答案很长：

创建简单的游乐场，以便在执行期间测试和检查所有内容：

import UIKit
import PlaygroundSupport
class MyViewController : UIViewController {

    private var theDescription:String?
    private var label:UILabel = UILabel()

    override func loadView() {
        let view = UIView()
        view.backgroundColor = .white

        label.frame = CGRect(x: 150, y: 200, width: 200, height: 20)
        label.text = "Hello World!"
        label.textColor = .black
        label.backgroundColor = .red

        view.addSubview(label)
        self.view = view
    }

    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)

        let alertController = UIAlertController(title: "Ajouter une description", message: "De quoi sagit il ?", preferredStyle:.alert)
        alertController.addTextField { (textField : UITextField) -> () in
            textField.placeholder = "Description"
            // you cant obtain value here - this block only for config purpose
            self.theDescription = textField.text
        }
        let okAction = UIAlertAction(title: "OK", style: .default) { (result : UIAlertAction) -> () in
            // instead use this approach
            self.theDescription = alertController.textFields?.first?.text
            self.createArtWithDescription(description: self.theDescription)
        }

        alertController.addAction(okAction)
        self.present(alertController, animated: true, completion: nil)
        //
    }

    func createArtWithDescription(description:String?) {
        DispatchQueue.main.async {
            self.label.text = description
        }
    }

}
// Present the view controller in the Live View window
PlaygroundPage.current.liveView = MyViewController()

有关UIAlertController

的更多信息

从uiAlertController中的textfield中检索内容

1 个答案: