我如何在Swift中创建一个UIAlertView ?

我一直在努力创建一个UIAlertView在Swift，但由于某种原因，我不能得到正确的声明，因为我得到这个错误:

无法找到一个超载的'init'接受提供的参数

我是这样写的:

let button2Alert: UIAlertView = UIAlertView(title: "Title", message: "message",
                     delegate: self, cancelButtonTitle: "OK", otherButtonTitles: nil)

然后我使用:

button2Alert.show()

到目前为止，它正在崩溃，我只是不能得到正确的语法。

当前回答

或者这样做

        let alert = UIAlertController(title: "Alert", message: "Saved Successfully", preferredStyle: UIAlertController.Style.alert)
        alert.addAction(UIAlertAction(title: "Ok", style: UIAlertAction.Style.default, handler: nil))
        self.present(alert, animated: true, completion: nil)

2020-08-13 20:15:37

其他回答

从UIAlertView类:

// UIAlertView已弃用。使用UIAlertController 将UIAlertControllerStyleAlert改为preferredStyle

在iOS 8上，你可以这样做:

let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.Default, handler: nil))
self.presentViewController(alert, animated: true, completion: nil)

UIAlertController是一个单独的类，用于创建和交互我们在ios8中知道的UIAlertViews和UIActionSheets。

编辑:处理动作:

alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: { action in
    switch action.style{
    case .Default:
        print("default")
        
    case .Cancel:
        print("cancel")
        
    case .Destructive:
        print("destructive")
    }
}}))

为Swift 3编辑:

let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.default, handler: nil))
self.present(alert, animated: true, completion: nil)

为Swift 4.x编辑:

let alert = UIAlertController(title: "Alert", message: "Message", preferredStyle: .alert)
alert.addAction(UIAlertAction(title: "OK", style: .default, handler: { action in
    switch action.style{
        case .default:
        print("default")
        
        case .cancel:
        print("cancel")
        
        case .destructive:
        print("destructive")
        
    }
}))
self.present(alert, animated: true, completion: nil)

2014-06-03 18:48:41

你可以使用标准的构造函数创建一个UIAlert，但是“遗留的”构造函数似乎不起作用:

let alert = UIAlertView()
alert.title = "Alert"
alert.message = "Here's a message"
alert.addButtonWithTitle("Understood")
alert.show()

2014-06-03 18:52:13

通过Swift 2的协议扩展，你可以创建一个为视图控制器提供默认实现的协议:

ShowsAlert.swift

import UIKit

protocol ShowsAlert {}

extension ShowsAlert where Self: UIViewController {
    func showAlert(title: String = "Error", message: String) {
        let alertController = UIAlertController(title: title, message: message, preferredStyle: .Alert)
        alertController.addAction(UIAlertAction(title: "Ok", style: .Default, handler: nil))
        presentViewController(alertController, animated: true, completion: nil)
    }
}

ViewController.swift

class ViewController: UIViewController, ShowsAlert {
    override func viewDidLoad() {
        super.viewDidLoad()
        showAlert(message: "Hey there, I am an error message!")
    }
}

2015-10-07 13:33:54

AlertView Swift 5及以上:-

let alert = UIAlertController(title: LocalizedStringConstant.alert, message: message, preferredStyle: UIAlertController.Style.alert)
alert.addAction(UIAlertAction(title: "Retry", style: .cancel, handler: { (_) in
     }))
self.present(alert, animated: true, completion: nil)

2020-07-10 05:01:41

试试这个。把波纹代码在按钮。

let alert = UIAlertController(title: "Your_Title_Text", message: "Your_MSG", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "Your_Text", style: UIAlertActionStyle.default, handler: nil))
self.present(alert, animated:true, completion: nil)

2017-12-01 08:00:06

我如何在Swift中创建一个UIAlertView ?

推荐文章

最新文章

标签