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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:
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5:
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:
//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8:
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)
}