Dismissing UIAlertController automatically

You can achieve the automatic dismiss of alert view by using dispatch_after of GCD.

Try below code :

    let delay = 0.5 * Double(NSEC_PER_SEC)
    let time = dispatch_time(DISPATCH_TIME_NOW, Int64(delay))
    dispatch_after(time, dispatch_get_main_queue()) { () -> Void in
        self.dismissPopover()
    }

Here, dismissCategoryPopover() is a custom method that will be called automatically after 0.5 seconds to dismiss the alert view.

I have a custom function updated for Swift 2.1 which uses a UIAlertController to simulate the Toast functionality in Android.

func showToast(withMessage message:String) {
    let menu = UIAlertController(title: nil, message: nil, preferredStyle: .ActionSheet)
    let cancel = UIAlertAction(title: message, style: .Cancel, handler: nil)
    menu.addAction(cancel)
    self.presentViewController(menu, animated: true, completion: nil)
    let delay = 1.5 * Double(NSEC_PER_SEC)
    let time = dispatch_time(DISPATCH_TIME_NOW, Int64(delay))
    self.tableView.setEditing(false, animated: true)
    dispatch_after(time, dispatch_get_main_queue()) { () -> Void in
        self.dismissViewControllerAnimated(true, completion: nil)
    }
}

This shows a complete, working solution for the OP.

Swift 3:

DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
    alert.dismiss(animated: false, completion: nil)
}