向 UIAlert 添加一个操作，将用户带到设置

Question

我有一个 UIAlert 通知用户他们没有互联网连接，他们需要互联网连接才能使用该应用程序。除了让他们通过点击 ok 操作来关闭警报外，我还希望有一个操作，当点击时将用户带到设置应用程序。

func displayAlert(title: String, message: String){

    var formEmpty = UIAlertController(title: title, message: message, preferredStyle: UIAlertControllerStyle.Alert)

    formEmpty.addAction((UIAlertAction(title: "Ok", style: .Default, handler: { (action) -> Void in

    })))

Answer 1

使用此代码。可能会有帮助。

override func viewDidAppear(animated: Bool) {
    var alertController = UIAlertController (title: "Title", message: "Go to Settings?", preferredStyle: .Alert)

    var settingsAction = UIAlertAction(title: "Settings", style: .Default) { (_) -> Void in
        let settingsUrl = NSURL(string: UIApplicationOpenSettingsURLString)
        if let url = settingsUrl {
            UIApplication.sharedApplication().openURL(url)
        }
    }

    var cancelAction = UIAlertAction(title: "Cancel", style: .Default, handler: nil)
    alertController.addAction(settingsAction)
    alertController.addAction(cancelAction)

    presentViewController(alertController, animated: true, completion: nil);
}

请注意 UIApplicationOpenSettingsURLString 仅在 iOS8.0 及之后可用，因此如果您的应用应支持 iOS7，您必须检查常量的可用性（或者如果使用 Swift 2.0 使用 #availability 关键字）。

Answer 2

您可以使用以下代码导航到设置：

let settingsUrl = NSURL(string: UIApplicationOpenSettingsURLString)
UIApplication.sharedApplication().openURL(settingsUrl!)

在您的函数中添加此代码后，您的函数将如下所示：

func displayAlert(title: String, message: String){

    var formEmpty = UIAlertController(title: title, message: message, preferredStyle: UIAlertControllerStyle.Alert)

    formEmpty.addAction((UIAlertAction(title: "Ok", style: .Default, handler: { (action) -> Void in
        //This will call when you press ok in your alertview
        let settingsUrl = NSURL(string: UIApplicationOpenSettingsURLString)
        UIApplication.sharedApplication().openURL(settingsUrl!)
    })))
}

Answer 3

对于iOS10，Swift3：

    let alert = UIAlertController(title: "Alert!", message: "your message here", preferredStyle: .alert)
    let settingsAction = UIAlertAction(title: "Settings", style: .default) { (_) -> Void in
    let settingsUrl = NSURL(string: UIApplicationOpenSettingsURLString)
    UIApplication.shared.open(settingsUrl as! URL, options: [:], completionHandler: nil)
    alert.addAction(settingsAction)
    present(alert, animated: true, completion: nil)

向 UIAlert 添加一个操作，将用户带到设置

Adding a action to a UIAlert that takes the user to settings

ios

swift

uialertaction