I am facing a very strange issue. When a UIAlertController is shown then in background layer of the current view controller Previous UIAlertController is shown. I can't post screenshot of that screen.
Below is code for showing the UIAlertController
func showActionAlertView(alertData:[String],vc:UIViewController,singleType:Bool) -> Void {
let Alert = UIAlertController(title: alertData.first, message: NSLocalizedString(alertData[1], comment: ""), preferredStyle: UIAlertControllerStyle.alert)
Alert.addAction(UIAlertAction(title: alertData[2], style: .default, handler: { (action: UIAlertAction!) in
self.delegate?.okAction(controller: vc)
}))
if !singleType
{
Alert.addAction(UIAlertAction(title: alertData.last, style: .cancel, handler: { (action: UIAlertAction!) in
print("Handle Cancel Logic here")
self.delegate?.cancelAction(controller: vc)
}))
}
vc.present(Alert, animated: true, completion: nil)
}
Thanks
You must access the above function inside the same view controller where the value of vc also needs to be same.
class OneVC: UIViewController{
//Inside viewDidLoad
// value for vc should be given same as of present class name (OneVC)
showActionAlertView(alertData:[String], vc:OneVC, singleType:Bool) -> Void
}
Related
My view is being dismissed through the previous button on the navigation bar. I think the correct term for that is that the view is being popped off the view stack. Now before actually dismissing the view I want to display a UIAlert asking the user to setup his/her address.
I've tried this but the UIAlert is not being show:
override func viewWillDisappear(animated: Bool) {
if let currentUser = ApiManager.sharedInstance.currentUser {
if !currentUser.hasAddress {
let alert = UIAlertController(title: "Missing address", message: "We see you're stilling missing an address, would you like set it now?", preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "yes".localized, style: .Default, handler: { (alertAction) in
let newViewController = LocationViewController()
newViewController.delegate = self
self.navigationController?.pushViewController(newViewController, animated: true)
}))
alert.addAction(UIAlertAction(title: "no".localized, style: .Default, handler: nil))
self.presentViewController(alert, animated: true, completion: nil)
}
}
}
In my console the following gets printed:
2016-10-28 16:58:47.380 gaifong[17096:14515422] Warning: Attempt to present <UIAlertController: 0x7fd7037e4cb0> on <gaifong.ProfileViewController: 0x7fd7048cc000> whose view is not in the window hierarchy!
You should add leftBarButtonItem on navigationItem and make an action to leftBarButtonItem where you can handle this.
in viewDidLoad
self.navigationItem.leftBarButtonItem = UIBarButtonItem(image: image, style: UIBarButtonItemStyle.Plain, target: self, action: #selector(self.goBack))
// Then handle the button selection
func goBack() {
if let currentUser = ApiManager.sharedInstance.currentUser {
if !currentUser.hasAddress {
let alert = UIAlertController(title: "Missing address", message: "We see you're stilling missing an address, would you like set it now?", preferredStyle: UIAlertControllerStyle.Alert)
alert.addAction(UIAlertAction(title: "yes".localized, style: .Default, handler: { (alertAction) in
// here you can pop to main controller
self.navigationController?.popViewControllerAnimated(true)
}))
alert.addAction(UIAlertAction(title: "no".localized, style: .Default, handler: nil))
self.presentViewController(alert, animated: true, completion: nil)
}
}
}
I want to make a "rate app" alert, but for some reason it gets deallocated before showing it.
Here's the code:
func showAlert() {
if #available(iOS 8.0, *)
{
let alertController = UIAlertController(title: "Rate App", message: "Rate this app now", preferredStyle: .Alert)
let neverAction = UIAlertAction(title: "Never Show This Again", style: .Destructive, handler: { (action: UIAlertAction) in
self.userDefaults.setBool(true, forKey: "rateAlertRejected")
})
let rateAction = UIAlertAction(title: "Rate Now", style: .Default, handler: { (action: UIAlertAction) in
// Rate App
})
let remindAction = UIAlertAction(title: "Remind Me Later", style: .Cancel, handler: nil)
alertController.addAction(rateAction)
alertController.addAction(neverAction)
alertController.addAction(remindAction)
presentViewController(alertController, animated: true, completion: nil)
}
else
{
// Identical code (using UIAlertView) for iOS 7 which works perfectly
}
}
The method executes (in certain conditions, but for testing purposes it does it every time) after a custom unwind segue.
Why do I have this problem? I used UIAlertController before but I had no issues.
According to your comment you show showAlert in
a method that executes after a custom unwind segue.
unwind segue dismisses the view heriarchy and therefore your alert
does not get reference to a view controller to show from.
To solve this, show your alert in the View controller you unwind to or wait for the alert controller action to be completed before unwinding.
I'm trying to show a UIAlertController in my ViewController in a function that's been called via an NSNotification. However I'm getting the error:
Attempt to present <UIAlertController: 0x7fe013d05d40> on <submarine.ViewController: 0x7fe011f20370> whose view is not in the window hierarchy!
The NSNotification is posted from a completion block (callback I guess) from something else in my UI. Because it's a callback it's failing to display. Hence I thought I'd try NSNotificationCentre to get around the problem without using the rootViewController to display the alert.
My code is:
override func viewDidAppear(animated: Bool) {
// Handle onboarding
if needsOnboarding() {
handleOnboarding() // This create the completion block that posts the NSNotification
}
NSNotificationCenter.defaultCenter().addObserver(self, selector: "showTermsAlert:", name:"showTermsAlert", object: nil)
}
func showTermsAlert(notification: NSNotification) {
let termsAlert:UIAlertController = UIAlertController(title: "Terms And Conditions", message: "Please view the terms below before accepting them.", preferredStyle: UIAlertControllerStyle.Alert)
termsAlert.addAction(UIAlertAction(title: "View Terms", style: .Default, handler: { (action: UIAlertAction!) in
UIApplication.sharedApplication().openURL(NSURL(string: "my_terms_url")!)
}))
termsAlert.addAction(UIAlertAction(title: "I Agree to the Terms", style: .Default, handler: { (action: UIAlertAction!) in
self.onboardingFinished()
}))
self.presentViewController(termsAlert, animated: true, completion: nil)
}
Has anyone got an idea why this is happening? I don't see why it's not in the window hierarchy - it's being presented from the self viewController and is created in a top-level function inside the VC.
Thanks!
EDIT: original code inside the handleOnboarding():
Library used: Onboard
func handleOnboarding() {
let secondPage = OnboardingContentViewController(title: "What's going on?", body: "Submarine routes your data through our network, around any filters and restrictions, giving you unrestricted and unmonitored internet access.", image: UIImage(named: "back"), buttonText: "Next") { () -> Void in
// do something here when users press the button, like ask for location services permissions, register for push notifications, connect to social media, or finish the onboarding process
}
secondPage.movesToNextViewController = true
let thirdPage = OnboardingContentViewController(title: "Terms of Use", body: "You must agree to our Terms of Use to use Submarine.\nIf you don't, please close Submarine.", image: UIImage(named: "back"), buttonText: "View Terms") { () -> Void in
let termsAlert:UIAlertController = UIAlertController(title: "Terms And Conditions", message: "Please view the terms below before accepting them.", preferredStyle: UIAlertControllerStyle.Alert)
termsAlert.addAction(UIAlertAction(title: "View Terms", style: .Default, handler: { (action: UIAlertAction!) in
UIApplication.sharedApplication().openURL(NSURL(string: "my_policy_url")!)
}))
termsAlert.addAction(UIAlertAction(title: "I Agree to the Terms", style: .Default, handler: { (action: UIAlertAction!) in
self.onboardingFinished()
}))
self.presentViewController(termsAlert, animated: true, completion: nil)
// NSNotificationCenter.defaultCenter().postNotificationName("showTermsAlert", object: nil)
}
// Image
let onboardingVC = OnboardingViewController(backgroundImage: UIImage(named: "back"), contents: [secondPage, thirdPage])
self.navigationController?.presentViewController(onboardingVC, animated: false, completion: nil)
}
This happen when the presenting view controller is no longer part of the controller hierarchy, and it's view is no longer in the view hierarchy of any window. Most likely, the controller was dismissed or popped, but it heard the notification and attempted to present the alert controller.
You should manage your controller states more carefully. Perhaps remove observer when the controller is dismissed or popped from your controller hierarchy.
There are a few things i'd change in your code. Add a call to super in viewDidAppear:, and stop using the NSNotifications for your presentation. You don't know what thread showTermsAlert will get called on with this pattern. You can make your intent more explicit by calling showTermsAlert directly, and this will also guarantee you're on the main thread.
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
// Handle onboarding
if needsOnboarding() {
self.showTermsAlert()
}
}
func showTermsAlert() {
let termsAlert:UIAlertController = UIAlertController(title: "Terms And Conditions", message: "Please view the terms below before accepting them.", preferredStyle: UIAlertControllerStyle.Alert)
termsAlert.addAction(UIAlertAction(title: "View Terms", style: .Default, handler: { (action: UIAlertAction!) in
UIApplication.sharedApplication().openURL(NSURL(string: "my_terms_url")!)
}))
termsAlert.addAction(UIAlertAction(title: "I Agree to the Terms", style: .Default, handler: { (action: UIAlertAction!) in
self.onboardingFinished()
}))
self.presentViewController(termsAlert, animated: true, completion: nil)
}
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)
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)
}
}