I want to navigate back to root view controller when someone says ok to the alert action. But the Alert action does not allow to access self.
What is the work around to get current navigation controller in AlertAction,
here is the code,
func buttonAction(sender:UIButton!)
{
let alertController = UIAlertController(title: "IQ", message:"Thank you for your feedback!", preferredStyle: .Alert)
alertController.addAction(okAction)
self.presentViewController(alertController, animated: true, completion: nil)
}
var okAction = UIAlertAction(title: "Menu", style:UIAlertActionStyle.Default) {
UIAlertAction in
NSLog("OK Pressed")
self.navigationController?.popToRootViewControllerAnimated(true) //error
}
All you have to do is to define a getter for the okAction property.
var okAction: UIAlertAction {
get {
return UIAlertAction(title: "Menu", style:UIAlertActionStyle.Default) {
UIAlertAction in
NSLog("OK Pressed")
self.navigationController?.popToRootViewControllerAnimated(true)
}
}
}
Tested in Xcode 7.1.1
You could do it this way instead:
let alert = UIAlertController(title: "Alert", message: "Message.", preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.Default, handler: { action in
self.navigationController?.popToRootViewControllerAnimated(true)
}))
self.presentViewController(alert, animated: true, completion: nil)
You need to dismiss the presented view controller (the Alert) before you try to pop from the navigation controller.
Related
I'm quite new to Swift (and coding in general) and to this website.
I'm having a little bit of an issue now. In my app, I have an alert when a timer reaches 0. In that alert, there are 2 buttons. One says "Share" and the other says "Continue". I want to make it such that when a user taps "Continue", the next Storyboard will be shown to them. As of now, whatever button I press will dismiss the alert, but stay on the same Storyboard. (It also prints to the console which button I pressed, but of course that's just for me to see).
How do I go about doing this? Here is my code, in case anyone wants to know.
let alert = UIAlertController(title: "Time's Up!", message: "What would you like to do now?", preferredStyle: .Alert)
let firstAction = UIAlertAction(title: "Continue", style: .Default) { (alert: UIAlertAction!) -> Void in
NSLog("You pressed button one")
}
let secondAction = UIAlertAction(title: "Share", style: .Default) { (alert: UIAlertAction!) -> Void in
NSLog("You pressed button two")
}
alert.addAction(firstAction)
alert.addAction(secondAction)
presentViewController(alert, animated: true, completion:nil)
Try with this:
// Create the alert controller
var alertController = UIAlertController(title: "Title", message: "Message", preferredStyle: .Alert)
// Create the actions
var okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.Default) {
UIAlertAction in
NSLog("OK Pressed")
let storyboard = UIStoryboard(name: "MyStoryboardName", bundle: nil)
let vc = storyboard.instantiateViewControllerWithIdentifier("someViewController") as UIViewController
self.presentViewController(vc, animated: true, completion: nil)
}
var cancelAction = UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel) {
UIAlertAction in
NSLog("Cancel Pressed")
//do whatever you want here
}
// Add the actions
alertController.addAction(okAction)
alertController.addAction(cancelAction)
// Present the controller
self.presentViewController(alertController, animated: true, completion: nil)
If you haven't already set your ViewControllerIdentifier:
You need to set the Identifier value that you can find on the right column
Here is the code that might help you. When you create a AlertController with actions, you can provide the actions and style of the button when you define them. In code below action is in the closure (Block) and style is defined as .Default or .Cancel
let alert = UIAlertController(title: "Time's Up!", message: "What would you like to do now?", preferredStyle: .Alert)
let firstAction = UIAlertAction(title: "Continue", style: .Default) { (alert: UIAlertAction!) -> Void in
// Action when you press button goes here
print("Here you show next storyboard item.")
// Code to push new ViewController. For example :
self.navigationController?.pushViewController(newVCInstance, animated: true)
}
let secondAction = UIAlertAction(title: "Share", style: .Default) { (alert: UIAlertAction!) -> Void in
print("Here you share things.")
// Code to share things.
}
let thirdAction = UIAlertAction(title: "Cancel", style: . Cancel) { (alert: UIAlertAction!) -> Void in
print("Just dismissing the Alert Controller.")
}
alert.addAction(firstAction)
alert.addAction(secondAction)
alert.addAction(thirdAction)
presentViewController(alert, animated: true, completion:nil)
This question already has answers here:
How to show UIAlertController from Appdelegate
(6 answers)
Closed 4 years ago.
I try the next code snippet:
var alert = UIAlertController(title: "Alert", message: "Cannot connect to : \(error!.localizedDescription)", preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.Default, handler: nil))
self.window?.rootViewController?.presentViewController(alert, animated: true, completion: nil)
in my AppDelegate, but it prints me the next error in console:
Warning: Attempt to present <UIAlertController: 0x7ff6cd827a30> on <Messenger.WelcomeController: 0x7ff6cb51c940> whose view is not in the window hierarchy!
How can I fix this error?
This is what i'm using now to do that.
var alertController = UIAlertController(title: "Title", message: "Any message", preferredStyle: .ActionSheet)
var okAction = UIAlertAction(title: "Yes", style: UIAlertActionStyle.Default) {
UIAlertAction in
NSLog("OK Pressed")
}
var cancelAction = UIAlertAction(title: "No", style: UIAlertActionStyle.Cancel) {
UIAlertAction in
NSLog("Cancel Pressed")
}
alertController.addAction(okAction)
alertController.addAction(cancelAction)
self.window?.rootViewController?.presentViewController(alertController, animated: true, completion: nil)
Swift 5:
let alert = UIAlertController(title: "Test", message:"Message", preferredStyle: UIAlertController.Style.alert)
// add an action (button)
alert.addAction(UIAlertAction(title: "OK", style: UIAlertAction.Style.default, handler: nil))
// show the alert
self.window?.rootViewController?.present(alert, animated: true, completion: nil)
As per Jorge's answer, updated for Swift 4
let alertController = UIAlertController(title: "Title", message: "Message", preferredStyle: .actionSheet)
let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default) {
UIAlertAction in
NSLog("OK Pressed")
}
let cancelAction = UIAlertAction(title: "CANCEL", style: UIAlertActionStyle.cancel) {
UIAlertAction in
NSLog("Cancel Pressed")
}
alertController.addAction(okAction)
alertController.addAction(cancelAction)
self.window?.rootViewController?.present(alertController, animated: true, completion: nil)
Swift 3.0 or above, Working in all condition , like in case of tab bar, in case of presented view etc ..
let alert = UIAlertController(title: "Test", message:"Message", preferredStyle: UIAlertControllerStyle.alert)
// add an action (button)
alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: nil))
// show alert
let alertWindow = UIWindow(frame: UIScreen.main.bounds)
alertWindow.rootViewController = UIViewController()
alertWindow.windowLevel = UIWindowLevelAlert + 1;
alertWindow.makeKeyAndVisible()
alertWindow.rootViewController?.present(alertController, animated: true, completion: nil)
I had the similar problem.
I have fixed it by presenting UIAlertController in Main Queue.
Code Looks like following.
let alert = UIAlertController(title: "My Title", message: "My Message", preferredStyle: .alert)
let actionYes = UIAlertAction(title: "Yes", style: .default, handler: { action in
print("action yes handler")
})
let actionCancel = UIAlertAction(title: "Cancel", style: .destructive, handler: { action in
print("action cancel handler")
})
alert.addAction(actionYes)
alert.addAction(actionCancel)
DispatchQueue.main.async {
self.window?.rootViewController?.present(alert, animated: true, completion: nil)
}
Have you tried using UIApplication.shared.keyWindow?.rootViewController?.present(...) ?
I suppose you are calling that code snippet from the applicationDidFinishLunchingWithOptions.
I tried it as a matter of fact because I had to. The thing is: what you are trying to do is correct but the ViewController that the AppDelegate makes and presents is about to be put on screen and before that, the code snippet tries to create an alertView and put in on top of non existent View of the RootViewController.
What I would do is move it to another delegate call which is guaranteed to be called after the RootViewController is presented.
func applicationDidBecomeActive(application: UIApplication) {
//This method is called when the rootViewController is set and the view.
// And the View controller is ready to get touches or events.
var alert = UIAlertController(title: "Alert", message: "Cannot connect to :", preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Click", style: UIAlertActionStyle.Default, handler: nil))
self.window?.rootViewController?.presentViewController(alert, animated: true, completion: nil)
}
But as always know the responsibility of the AppDelegate. It is to handle the application lifecycle and application wide delegate calls and events. If putting code here makes sense, then do it. But if you will be better off putting the code on the rootViewController or other parts then think about it too.
Anyway, hope it helps. Cheers!
I would suggest NOT doing this in the AppDelegate. The App Delegate it intended to handle Delegate functions from the OS rather than implementing things like alert views.
If you are wanting to present an alert view here to be shown at the start of the app I would do this by implementing it in your first view controller.
I am trying to popViewController to the previous View Controller in the navigation stack after an alertView. As of now, my program will not run the popViewController method, since the alertView is in the way, and brings up the error:
UINavigationController 0x17670900 while an existing transition or presentation is occurring; the navigation stack will not be updated.
How do I go about running the popViewController method after the user clicks OK from the alertView? Do I have to set a delegate which detects when the used clicks OK?
Here is my code:
//alertView after Picture saved
let alertView = UIAlertController(title: "Success!", message: "Record Saved to Database", preferredStyle: .Alert)
alertView.addAction(UIAlertAction(title: "Ok", style: .Default, handler: nil))
self.presentViewController(alertView, animated: true, completion: nil)
//go to previous controller using popViewController, doesnt work, brings up error message
if let navController = self.navigationController {
navController.popViewControllerAnimated(true)
}
You need to pop the view controller when user presses the Ok button from AlertView.
let alertView = UIAlertController(title: "Success!", message: "Record Saved to Database", preferredStyle: .Alert)
let OKAction = UIAlertAction(title: "Ok", style: .Default) { (action) in
// pop here
if let navController = self.navigationController {
navController.popViewControllerAnimated(true)
}
}
alertView.addAction(OKAction)
self.present(alertView, animated: true, completion: nil)
You can put the "popViewControllerAction" inside an alert action like this.
func alertMethod() {
var okAlertController = UIAlertController(title: NSLocalizedString("Your title", comment: ""), message: "Your message", preferredStyle:
UIAlertControllerStyle.Alert)
let okAction = UIAlertAction(title: NSLocalizedString("Ok", comment: ""), style: UIAlertActionStyle.Default) { (UIAlertAction) -> Void in
// your action - navController.popViewControllerAnimated(true)
}
let cancelAction = UIAlertAction(title: NSLocalizedString("Cancel", comment: ""), style: UIAlertActionStyle.Default) { (UIAlertAction) -> Void in
// your action
}
}
saveAlertController.addAction(okAction)
saveAlertController.addAction(cancelAction)
self.presentViewController(okAlertController, animated: true, completion: nil)
}
That should work, in that case the method gets called after the user presses a button...
The UIAlertViewController shows all my text but on clicking doesn't switch to the other View. Here's the code:
let alertController = UIAlertController(title: "Risposta Esatta", message:"", preferredStyle: UIAlertControllerStyle.Alert)
alertController.addAction(UIAlertAction(title: "Avanti", style:UIAlertActionStyle.Default,handler: {(UIAlertAction) in
let secondViewController:SecondViewController = SecondViewController()
self.presentViewController(secondViewController, animated: true, completion: nil)
}))
This just worked for me:
#IBAction func choiceBtn(sender: UIButton) {
let alertController = UIAlertController(title: "Hello!", message: "This is Alert sample.", preferredStyle: .Alert)
let otherAction = UIAlertAction(title: "OK", style: .Default) {
action in println("pushed OK!")
}
let cancelAction = UIAlertAction(title: "CANCEL", style: .Cancel) {
action in self.performSegueWithIdentifier("VC2", sender: self)
}
alertController.addAction(otherAction)
alertController.addAction(cancelAction)
presentViewController(alertController, animated: true, completion: nil)
}
I created a modal presented segue from VC1 to VC2 and also named the identifier VC2. This code I adapted from the GitHub UIAlertController example here:
https://github.com/eversense/Swift-UIAlertController-Example
There was no segue to another ViewController, so I added that to show you.
I have a view controller which contains a sub-view. And inside the sub-view class, I may need to pop out an alert when some condition is satisfied.
class GameViewController: UIViewController {
#IBOutlet var gameBoardUIView: GameBoardUIView
...
}
class GameBoardUIView: UIView {
...
func move() {
if !gameBoard.checkNextMoveExist() {
var alert = UIAlertController(title: "Game Over", message: nil, preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Take Me Back", style: UIAlertActionStyle.Cancel, handler: {(action: UIAlertAction!) in
println("Taking user back to the game without restarting")
}))
alert.addAction(UIAlertAction(title: "New Game", style: UIAlertActionStyle.Destructive, handler: {(action: UIAlertAction!) in
println("Starting a new game")
self.restartGame()
}))
// This is where the question is
// self.presentViewController(alert, animated: true, completion: nil)
}
}
}
As you can see from the code, I cannot call presentViewController function to show the alert because my sub view is not a controller class. Should I somehow create a week reference to the parent controller inside the sub-view? What would be the best practice to implement such reference?
Swift 4
Just present the alert in UIApplication windows in root view controller:
let title = "Some title"
let message = "body message"
let alert = UIAlertController(title: title, message: message, preferredStyle: .alert)
let action = UIAlertAction(title: "Aceptar", style: .cancel, handler: nil)
alert.addAction(action)
UIApplication.shared.keyWindow?.rootViewController?.present(alert, animated: true, completion: nil)
there are couple of ways how you can catch a UIViewController in your UIView.
you can make any of your view controllers as a delegate to show an alert;
you can pass a view controller's reference to your view; and
in general you can always grab the rootViewController anywhere in your code.
you need to call the dismissViewControllerAnimated(_: completion:) on the same view controller when you'd like to dismiss your alert later.
thus, I'd do such a quick solution for your case:
func move() {
if !gameBoard.checkNextMoveExist() {
let rootViewController: UIViewController = UIApplication.sharedApplication().windows[0].rootViewController
var alert = UIAlertController(title: "Game Over", message: nil, preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "Take Me Back", style: UIAlertActionStyle.Cancel, handler: {(action: UIAlertAction!) in
rootViewController.dismissViewControllerAnimated(true, completion: nil)
println("Taking user back to the game without restarting")
}))
alert.addAction(UIAlertAction(title: "New Game", style: UIAlertActionStyle.Destructive, handler: {(action: UIAlertAction!) in
rootViewController.dismissViewControllerAnimated(true, completion: nil)
println("Starting a new game")
self.restartGame()
}))
rootViewController.presentViewController(alert, animated: true, completion: nil)
}
}