Dismiss UIAlertView after 5 Seconds Swift

问题

I've created a UIAlertView that contains a UIActivityIndicator. Everything works great, but I'd also like the UIAlertView to disappear after 5 seconds.

How can I Dismiss my UIAlertView after 5 seconds?

 var alert: UIAlertView = UIAlertView(title: "Loading", message: "Please wait...", delegate: nil, cancelButtonTitle: "Cancel");

 var loadingIndicator: UIActivityIndicatorView = UIActivityIndicatorView(frame: CGRectMake(50, 10, 37, 37)) as UIActivityIndicatorView
 loadingIndicator.center = self.view.center;
 loadingIndicator.hidesWhenStopped = true
 loadingIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.Gray
 loadingIndicator.startAnimating();

 alert.setValue(loadingIndicator, forKey: "accessoryView")
 loadingIndicator.startAnimating()

 alert.show()

回答1:

You can dismiss your UIAlertView after a 5 second delay programmatically, like so:

alert.show()

// Delay the dismissal by 5 seconds
let delay = 5.0 * Double(NSEC_PER_SEC)
var time = dispatch_time(DISPATCH_TIME_NOW, Int64(delay))
dispatch_after(time, dispatch_get_main_queue(), {
    alert.dismissWithClickedButtonIndex(-1, animated: true)
})

回答2:

A solution to dismiss an alert automatically in Swift 3 and Swift 4 (Inspired by part of these answers: [1], [2], [3]):

// the alert view
let alert = UIAlertController(title: "", message: "alert disappears after 5 seconds", preferredStyle: .alert)
self.present(alert, animated: true, completion: nil)

// change to desired number of seconds (in this case 5 seconds)
let when = DispatchTime.now() + 5
DispatchQueue.main.asyncAfter(deadline: when){
  // your code with delay
  alert.dismiss(animated: true, completion: nil)
}

Result:

回答3:

in swift 2 you can do this. Credit to @Lyndsey Scott

 let alertController = UIAlertController(title: "youTitle", message: "YourMessage", preferredStyle: .Alert)
                self.presentViewController(alertController, animated: true, completion: nil)
                let delay = 5.0 * Double(NSEC_PER_SEC)
                let time = dispatch_time(DISPATCH_TIME_NOW, Int64(delay))
                dispatch_after(time, dispatch_get_main_queue(), {
                    alertController.dismissViewControllerAnimated(true, completion: nil)
                })

回答4:

For swift 4 you can use this code

let alertController = UIAlertController(title:"Alert",message:nil,preferredStyle:.alert)
self.present(alertController,animated:true,completion:{Timer.scheduledTimer(withTimeInterval: 5, repeats:false, block: {_ in
    self.dismiss(animated: true, completion: nil)
})}

回答5:

Create the alert object as a global variable. You can use a NSTimer for this purpose.

var timer = NSTimer.scheduledTimerWithTimeInterval(5.0, target: self, selector: Selector("dismissAlert"), userInfo: nil, repeats: false)


func dismissAlert()
{
    // Dismiss the alert from here
    alertView.dismissWithClickedButtonIndex(0, animated: true)

}

NOTE:

Important: UIAlertView is deprecated in iOS 8. (Note that UIAlertViewDelegate is also deprecated.) To create and manage alerts in iOS 8 and later, instead use UIAlertController with a preferredStyle of UIAlertControllerStyleAlert.

Reference : UIAlertView

回答6:

For Swift 3

let alert = UIAlertController(title: “Alert”, message: “Message”,preferredStyle: UIAlertControllerStyle.alert)
self.present(alert, animated: true, completion: nil)
 DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + Double((Int64)(5.0 * Double(NSEC_PER_SEC))) / Double(NSEC_PER_SEC), execute: {() -> Void in
     alert.dismiss(animated: true, completion: {() -> Void in
 })
})

回答7:

I'm not an expert but this works for me and I guess is easier

let alert = UIAlertController(title: "", message: "YOUR MESSAGE", preferredStyle: .alert)
present(alert, animated: true) {
   sleep(5)
   alert.dismiss(animated: true)
}

回答8:

//Generic Function For Dismissing alert w.r.t Timer

/** showWithTimer */
public func showWithTimer(message : String?, viewController : UIViewController?) {

    let version : NSString = UIDevice.current.systemVersion as NSString
    if  version.doubleValue >= 8 {
        alert = UIAlertController(title: "", message: message, preferredStyle:.alert)
        viewController?.present(alert ?? UIAlertController(), animated:true, completion:nil)
        let when = DispatchTime.now() + 5
        DispatchQueue.main.asyncAfter(deadline: when){
            self.alert?.dismiss(animated: true, completion: nil)
        }
    }
}

回答9:

@ronatory 's answer in c#

var when = new DispatchTime(DispatchTime.Now, 
TimeSpan.FromSeconds(5));
DispatchQueue.MainQueue.DispatchAfter(when, () =>
{
    // your code with delay
    alertController.DismissModalViewController(true);
});

回答10:

In iOS 8.0+ UIAlertController inherits from UIViewController, so, it is just that, a view controller. So, all the restrictions apply. That's why when there's a possibility that the view gets dismissed by the user, it's not entirely safe to try to dismiss it without proper checks.

In the following snippet there's an example of how this can be achieved.

func showAutoDismissableAlert(
      title: String?,
      message: String?,
      actions: [MyActionWithPayload], //This is just an struct holding the style, name and the action in case of the user selects that option
      timeout: DispatchTimeInterval?) {

  let alertView = UIAlertController(
      title: title,
      message: message,
      preferredStyle: .alert
  )

  //map and assign your actions from MyActionWithPayload to alert UIAlertAction
  //(..)

  //Present your alert
  //(Here I'm counting on having the following variables passed as arguments, for a safer way to do this, see https://github.com/agilityvision/FFGlobalAlertController) 
  alertView.present(viewController, animated: animated, completion: completion)


  //If a timeout was set, prepare your code to dismiss the alert if it was not dismissed yet
  if let timeout = timeout {
    DispatchQueue.main.asyncAfter(
       deadline: DispatchTime.now() + timeout,
       execute: { [weak alertView] in
            if let alertView = alertView, !alertView.isBeingDismissed {
                alertView.dismiss(animated: true, completion: nil)
            }
        }
    }
}

来源：https://stackoverflow.com/questions/27613926/dismiss-uialertview-after-5-seconds-swift