I'm trying to present a view controller once the QRCode reader has been dismissed, however when doing this the QRCode reader view controller is presented again. The code snippet below shows the method and how I'm dismissing the view and how I'm trying to present the next view controller. Any idea on why the QR reader view controller keeps presenting its self when I try to present a different controller.
func readerDidCancel(_ reader: QRCodeReaderViewController) {
dismiss(animated: true, completion: nil)
present(ClockInOrOutViewController(), animated: true, completion: nil)
}
You have to call the present inside the completion handler of the dismiss.
func readerDidCancel(_ reader: QRCodeReaderViewController) {
weak var presentingViewController = self.presentingViewController
self.dismiss(animated: true, completion: {
presentingViewController?.present(ClockInOrOutViewController(), animated: true, completion: nil)
})
}
If this does not work, it means your presenting view controller has also been removed somehow. (dismissed/popped?)
You can't present view controller while other view controller is dismissing and also present on dismissing view controller.
You can do something like this:
func readerDidCancel(_ reader: QRCodeReaderViewController) {
let presenting = self.presentingViewController
dismiss(animated: true, completion: {
presenting?.present(ClockInOrOutViewController(), animated: true, completion: nil)
})
}
Related
If I present a ViewController like so:
let authViewController = authUI!.authViewController()
authViewController.modalPresentationStyle = .overCurrentContext
self.present(authViewController, animated: true, completion: nil)
I would like to know when the ViewController has been dismissed. I have tried the following:
let authViewController = authUI!.authViewController()
authViewController.modalPresentationStyle = .overCurrentContext
self.present(authViewController, animated: true, completion: {
print("View Dismissed")
})
but that only lets me know if the view was presented successfully. This ViewController was not created by me so I can't change the viewWillDissapear method.
Whole answer is predicated on an assumption that OP doesnt have access to authViewController code
If you dont have access to authViewController code, lousy solution would be to use viewWillAppear of your view controller to find when auth view controller is dismissed.
Basically when you present/push any viewController over your existing view controller, your view controller's viewWillDisappear will be called similarly when presented/pushed view controller is dismissed, or popped out viewWillAppear will be called.
Because viewWillAppear might get called for other reasons as well and you wouldnt wanna confuse it as authViewController dismiss, use a boolean
private var shouldMonitorAuthViewControllerDismiss = false //declared a instance property
Set the boolean to true when you actually present the authViewController
let authViewController = authUI!.authViewController()
authViewController.modalPresentationStyle = .overCurrentContext
self.present(authViewController, animated: true, completion: {
shouldMonitorAuthViewControllerDismiss = true
})
Finally in your viewWillAppear
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(true)
if shouldMonitorAuthViewControllerDismiss {
//auth view controller is dismissed
}
shouldMonitorAuthViewControllerDismiss = false
}
I am trying to dismiss VC b from VC c where VC c is a popover and has a button for sign out but it is not working.
The structure of the flow is
VC a ----presents modally----> VC b ----presents a popover----> VC c
When the button in the popover is clicked the VC c and VC b must be dismissed so that (VC a)ViewWillAppear is called.
Try this:
You can dismiss your presentingViewController from child view controller as follow
self.presentingViewController?.dismiss(animated: true, completion: nil)
When you add a ViewController as childViewController
self.parent?.dismiss(animated: true, completion: nil)
If this view controller is a child of a containing view controller (e.g. a navigation controller or tab bar
controller,)
weak open var parent: UIViewController? { get }
The view controller that was presented by this view controller or its nearest ancestor.
open var presentedViewController: UIViewController? { get }
The view controller that presented this view controller (or its farthest ancestor.)
open var presentingViewController: UIViewController? { get }
If ViewControllers have hierarchy like
VC a ----presents as self.present(objects, animated: true, completion: nil) modally----> VC b ---- presents as self.present(objects, animated: true, completion: nil) popover----> VC c
And there are a button on VC c to move back to VC a then you can use:
self.presentingViewController?.presentingViewController?.dismiss(animated: true, completion: nil)
First of all try to dismiss VC b from itself, not presenting the VC c just to check if it works, using: self.dismiss(animated: true, completion: nil) or if VC b is embedded in a navigation controller, like this: self.navigationController?.dismiss(animated: true, completion: nil)
If the one from above works, I would suggest you implement the delegation protocol, where VC c will delegate to VC b the dismissal, whenever it should be done. You could also use a completion block for that, containing the dismiss code.
Hope this works
// Call inside View controller C
self.presentingViewController?.dismissViewControllerAnimated(false, completion: nil)
self.presentingViewController?.dismissViewControllerAnimated(true, completion: nil)
`protocol ModalHandler {
func modalDismissed()
Class SecondViewController: UIViewController, ModalHandler {
func modalDismissed() {
self.dismiss(animated: false, completion: nil)
}
func open3rdController() {
let thirdVC = ThirdViewController(_ )
thirdVC.delegate = self
self.present(thirdVC, animated: true, completion: nil)
}
class ThirdViewController: UIViewController {
func dismiss() {
self.delegate.modalDismissed()
}
}
`
Whats about a Presenter or a Coordinator.
This instance will initialize all these VCs and also present them.
From there you can also dismiss them.
In my TabBarViewController, I create a UINavigationController and present it as a modal.
var navController = UINavigationController()
let messageVC = self.storyboard?.instantiateViewControllerWithIdentifier("MessagesViewController") as! MessagesViewController
self.presentViewController(self.navController, animated: false, completion: nil)
self.navController.pushViewController(messageVC, animated: false)
Inside my MessageViewController, this is how I want to dismiss it:
func swipedRightAndUserWantsToDismiss(){
if self == self.navigationController?.viewControllers[0] {
self.dismissViewControllerAnimated(true, completion: nil) //doesn't deinit
}else{
self.navigationController?.popViewControllerAnimated(true) //deinits correctly
}
}
deinit{
print("Deinit MessagesViewController")
}
The problem is that when I get to the root View Controller and try to dismiss both the child and the UINavigationController, my MessagesViewController deinit does not get called. Something's holding on to it -- most likely UINavigationController
Your controller hierarchy looks like this:
UITabViewController
|
| presents
|
UINavigationController
|
| contains view controllers
|
[root, MessagesViewController]
Now, if you are inside MessagesViewController, then its navigationController is the one that is being presented and that's the one you should be dismissing but calling dismiss on MessagesViewController should work too.
However, the problem is that dismissing the navigation controller won't remove its view controllers. It seems you are holding to your navigation controller (since you are presenting it using self.navController) so the state will become
UITabViewController
|
| self.navController holds a reference to
|
UINavigationController
|
| contains view controllers
|
[root, MessagesViewController]
To properly destroy MessagesViewController you will have to either let go of the navController or you will have to pop to root (thus removing MessagesViewController from view hierarchy).
The typical solution would be not to save a reference to navController at all. You could always create a new UINavigationController when presenting.
Another solution is using a delegate - instead of dismissing from inside MessagesViewController, let it call back to the presenter, which would call
self.navController.dismiss(animated: true) {
self.navController = nil
}
Try this
func swipedRightAndUserWantsToDismiss(){
self.navigationController.dismissViewControllerAnimated(false, completion:nil);
}
You can use the following to correctly dismiss a UINavigationController that's presented as a modal in Swift 4:
self.navigationController?.popViewController(animated: true)
if you want to just present a viewcontroller, then directly you can present that viewcontroller and no need to take a navigation controller for that particular viewcontroller.
But when we need to navigate from that presented view controller then we need to take a view controller as a root view of navigation controller. So that we can navigate from that presented view controller.
let messageVC = self.storyboard?.instantiateViewControllerWithIdentifier("MessagesViewController") as! MessagesViewController
let MynavController = UINavigationController(rootViewController: messageVC)
self.presentViewController(MynavController, animated: true, completion: nil)
and from that presented view controller, you can push to another view controller and also pop from another view controller.
And from presented view controller, here messageVC, we have to dismiss that as
func swipedRightAndUserWantsToDismiss() {
self.dismiss(animated: true, completion: nil)
}
which will dismiss messageVC successfully and come back to origin viewcontroller from where we have presented messageVC.
This is the right flow to perform presentViewController with navigation controller, to continue the navigation between the view controllers.
And for more if you are not sure that messageVC is presented or pushed, then you can check it by this answer.
And the swift version to check that is
func isModal() -> Bool {
if((self.presentingViewController) != nil) {
return true
}
if(self.presentingViewController?.presentedViewController == self) {
return true
}
if(self.navigationController?.presentingViewController?.presentedViewController == self.navigationController) {
return true
}
if((self.tabBarController?.presentingViewController?.isKindOfClass(UITabBarController)) != nil) {
return true
}
return false
}
So our final action to dismiss is like
func swipedRightAndUserWantsToDismiss() {
if self.isModal() == true {
self.dismiss(animated: true, completion: nil)
}
else {
self.navigationController?.popViewControllerAnimated(true)
}
}
No need to have member for navController. Use following code to present your MessagesViewController.
let messageVC = self.storyboard?.instantiateViewControllerWithIdentifier("MessagesViewController") as! MessagesViewController
let pesentingNavigationController = UINavigationController(rootViewController: messageVC)
self.presentViewController(pesentingNavigationController, animated: true, completion: nil)
Your dismiss view controller code will be
func swipedRightAndUserWantsToDismiss() {
self.navigationController.dismiss(animated: true, completion: nil)
}
I suggest you use the other initializer for your UINavigationController:
let messageVC = self.storyboard?.instantiateViewControllerWithIdentifier("MessagesViewController") as! MessagesViewController
let navController = UINavigationController(rootViewController: messageVC)
self.presentViewController(self.navController, animated: true, completion: nil)
To dimiss, simply do
func swipedRightAndUserWantsToDismiss() {
self.navigationController.dismissViewControllerAnimated(true, completion: nil)
}
This is how I solve the problem in Objective C.
You can call dismissViewControllerAnimated:NO on your self.navigationController itself.
Objective C
[self.navigationController dismissViewControllerAnimated:NO completion:nil];
Swift
self.navigationController.dismissViewControllerAnimated(false, completion: nil)
In Swift 3 this is achieved with:
self.navigationController?.dismiss(animated: true, completion: nil)
I am presenting two view controller like so
self.presentViewController(choosePlace, animated: true, completion: nil)
self.presentViewController(shareController, animated: true, completion: nil)
and I want to dismiss both of them like this:
println("parent \(self.parentViewController)")
self.dismissViewControllerAnimated(true, completion: {
self.parentViewController?.dismissViewControllerAnimated(true, completion: nil)
})
self.parentViewController is always nil though. How can I dismiss two at the same time?
You can:
self.dismissViewControllerAnimated(true, completion: {
self.presentingViewController?.dismissViewControllerAnimated(true, completion: nil)
})
So, make sure that you are presenting your view controllers in order:
parentViewController -> choosePlace -> shareController
(arrows indicate "self.presentViewController")
Swift 4
There where some issue I faced while trying Michael Voline's answer.
As the comment on the answer it did not work for me. it was because of the presentingViewController was nil.
So we need to set in a different property say presentingController but this will not work if you are setting it on the viewDidLoad
private var presentingController: UIViewController?
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
presentingController = presentingViewController
}
then
dismiss(animated: false, completion: {
self.presentingController?.dismiss(animated: false)
})
I made the animation false so that the user will not see the UIof presenting view controller in the split seconds of dismissing.
You can reference the presenting view controller during the function 'viewWillDisappear' of your view controller (i.e ShareController dismisses choosePlace just before it leaves scope).
//place the below in shareController
override func viewWillDisappear(_ animated: Bool) {
self.presentingViewController?.dismiss(animated: false, completion: nil)
}
If Michael Voline's solution doesn't work , try the following code.
let customViewController = self.presentingViewController as? CustomViewController
self.dismiss(animated: true) {
customViewController?.dismiss(animated: true, completion: nil)
}
I am trying to dismiss a ViewController in swift by calling dismissViewController in an IBAction
#IBAction func cancel(sender: AnyObject) {
self.dismissViewControllerAnimated(false, completion: nil)
println("cancel")
}
#IBAction func done(sender: AnyObject) {
self.dismissViewControllerAnimated(false, completion: nil)
println("done")
}
I could see the println message in console output but ViewController never gets dismissed. What could be the problem?
From you image it seems like you presented the ViewController using push
The dismissViewControllerAnimated is used to close ViewControllers that presented using modal
Swift 2
navigationController.popViewControllerAnimated(true)
Swift 4
navigationController?.popViewController(animated: true)
dismiss(animated: true, completion: nil)
I have a solution for your problem. Please try this code to dismiss the view controller if you present the view using modal:
Swift 3:
self.dismiss(animated: true, completion: nil)
OR
If you present the view using "push" segue
self.navigationController?.popViewController(animated: true)
if you do this i guess you might not get println message in console,
#IBAction func cancel(sender: AnyObject) {
if(self.presentingViewController){
self.dismissViewControllerAnimated(false, completion: nil)
println("cancel")
}
}
#IBAction func done(sender: AnyObject) {
if(self.presentingViewController){
self.dismissViewControllerAnimated(false, completion: nil)
println("done")
}
}
In Swift 3.0 to 4.0 it's as easy as typing this into your function:
self.dismiss(animated: true, completion: nil)
Or if you're in a navigation controller you can "pop" it:
self.navigationController?.popViewController(animated: true)
embed the View you want to dismiss in a NavigationController
add a BarButton with "Done" as Identifier
invoke the Assistant Editor with the Done button selected
create an IBAction for this button
add this line into the brackets:
self.dismissViewControllerAnimated(true, completion: nil)
Use:
self.dismiss(animated: true, completion: nil)
instead of:
self.navigationController.dismissViewControllerAnimated(true, completion: nil)
From Apple documentations:
The presenting view controller is responsible for dismissing the view controller it presented
Thus, it is a bad practise to just invoke the dismiss method from it self.
What you should do if you're presenting it modal is:
presentingViewController?.dismiss(animated: true, completion: nil)
If you presenting a controller without a Navigation Controller, you can call the following code from a method of the presented controller.
self.presentingViewController?.dismiss(animated: true, completion: nil)
If your ViewController is presented modally, optional presentingViewController will be not nil and the code will be executed.
Based on my experience, I add a method to dismiss me as extension to UIViewController:
extension UIViewController {
func dismissMe(animated: Bool, completion: (()->())?) {
var count = 0
if let c = self.navigationController?.viewControllers.count {
count = c
}
if count > 1 {
self.navigationController?.popViewController(animated: animated)
if let handler = completion {
handler()
}
} else {
dismiss(animated: animated, completion: completion)
}
}
}
Then I call this method to dismiss view controller in any UIViewController subclass. For example, in cancel action:
class MyViewController: UIViewController {
...
#IBAction func cancel(sender: AnyObject) {
dismissMe(animated: true, completion: nil)
}
...
}
Since you used push presented viewController, therefore, you can use
self.dismiss(animated: false, completion: nil)
Don't create any segue from Cancel or Done to other VC and only write this code your buttons #IBAction
#IBAction func cancel(sender: AnyObject) {
dismiss(animated: false, completion: nil)
}
So if you wanna dismiss your Viewcontroller use this. This code is written in button action to dismiss VC
#IBAction func cancel(sender: AnyObject) {
dismiss(animated: true, completion: nil)
}
Here is the one way to dismiss present view controller and move back to previous view controller. You can do this through Storyboard only.
Open Storyboard
Right click on Cancel button and drag it to previous view controller, where you want to move back to previous controller
Now release the right click and you can see some actions which performs on cancel button
Now choose "popover present" option from list
Now you can dismiss your current view by click on cancel button
Please try this, It's working with me.
Second Way - Use - navigationController.popViewControllerAnimated(true)
Best luck..
For reference, be aware that you might be dismissing the wrong view controller. For example, if you have an alert box or modal showing on top of another modal. (You could have a Twitter post alert showing on top of your current modal alert, for example). In this case, you need to call dismiss twice, or use an unwind segue.
Try this:
#IBAction func close() {
dismiss(animated: true, completion: nil)
}
If you using the present method in the parent VC then you should call this function, to dismiss the child VC use this
self.dismiss(animated: true, completion: nil)
if you calling child VC by using push method, to dismiss the child VC use this
self.navigationController?.popViewController(animated: true)
If you are presenting a ViewController modally, and want to go back to the root ViewController, take care to dismiss this modally presented ViewController before you go back to the root ViewController otherwise this ViewController will not be removed from Memory and cause Memory leaks.
In Swift 3.0
If you want to dismiss a presented view controller
self.dismiss(animated: true, completion: nil)
In Swift 4.1 and Xcode 9.4.1
If you use pushViewController to present new view controller, use this
self.navigationController?.popViewController(animated: false)
#IBAction func back(_ sender: Any) {
self.dismiss(animated: false, completion: nil)
}