I have a view controller VC1 that is presented modally over full screen from some other VC0. In my storyboard I have a modal segue from VC1 to VC2 also presenting over full screen. When in my app I can plainly see VC2 over VC1 over VC0, because some parts of their views are transparent. Perfect.
However, I'm going to reuse VC2 many times so I don't want to have a segue to it for each controller in my storyboard, so I want to accomplish this same thing programmatically. However, when I call presentViewController:animated:completion in VC1 to present VC2, the view of VC1 disappears when the modal transition is complete. When VC2 is dismissed, the view of VC1 reappears when the transition animation is complete.
How can I get the same effect programmatically as when I'm using the storyboard segue?
let newView = self.storyboard!.instantiateViewControllerWithIdentifier("NewViewController") as! NewViewController
newView.modalPresentationStyle = UIModalPresentationStyle.OverFullScreen
self.presentViewController(newView, animated: true, completion: nil)
You can only present on a visible controller, which is usually the rootViewController. But when there is a modally-presented controller, it covers the root controller, so you can't use that. But you can present on the modal, which is accessed though rootViewController.prsentedViewController. Here's some code:
let rootVC = window?.rootViewController
let presentingVC = (rootVC?.presentedViewController ?? rootVC)
presentingVC?.present(myController, animated: true, completion: nil)
You don't need to change the modalPresentationStyle.
You need to set the modalPresentationStyle property of the presented controller to UIModalPresentationOverFullScreen. Set that property just before you call presentViewController:animated:completion.
Related
As you can see i have an initial view controller with label in it "Initial ViewController". In this view controller i use below code to go to selected tab of Tab Bar Controller
let vc1 = sb.instantiateViewController(withIdentifier: "tabbar") as! UITabBarController
vc1.selectedIndex = selected
let controllers = [vc1]
navigationController!.setViewControllers(controllers, animated: true)
In my First View, there's a button "Present VC" which presents "Presented View".
let vc1 = sb.instantiateViewController(withIdentifier: "PresentedVC") as! PresentedVC
present(vc1, animated: true, completion: nil)
Now i want to go back from presented vc to root vc(Initial View Controller). I can do this with:
let viewController = self.storyboard?.instantiateViewController(withIdentifier: "FirstNavigationController") as! FirstNavigationController
UIApplication.shared.keyWindow?.rootViewController = viewController
but this instantiate Initial View Controller every time and views remain in memory. How can i go back to Initial View Controller without instantiating it?
PS: FirstNavigationController is initial Navigation Controller.
At the very beginning you remove the initial view controller by doing this:
navigationController!.setViewControllers(controllers, animated: true)
All the previous viewControllers are gone now and replaced with the tabbar controller and its children.
If you want to go back to the initial controller, you will have to push the tabbar onto the stack instead of replacing everything with it. E.g.
navigationController?.pushViewController(tabbarVc, animated: true)
First when you did this
navigationController!.setViewControllers(controllers, animated: true)
the initial VC is deallocated (if it has not a strong references)
to keep it you can use push , pop instead of setViewControllers but note it may cause memory issues if you have heavy processing in your app as it will remain in navigationController stack
You are missing the concept between "Presenting" or "Setting" View Controller & "Navigating" the View Controller. You will get the answer, once you understood the concept. Here, it is..
When you are setting the ViewController, you are completely replacing the stack container to the new view controller. the way you did it here:
navigationController!.setViewControllers(controllers, animated: true)
In this case, STACK holds the addresses of the latest set/presented ViewControllers that means previous whole ViewController vanished.
On the other hand, if you are navigating to other view controller by pushing it. you can go back to previous controller by simple popping the ViewController address from stack. or to next ViewController by pushing
e.g:
self.navigationController?.pushViewController(tabbarVc, animated: true)
self.navigationController?.popViewController(animated: true)
Summary:
If you push TabBarController then, only you will get InitialVC.
Now, in your case, you are setting the ViewController and hence, you are not getting InivtialVC. Try Pushing tabbarVC This will work.
navigationController?.pushViewController(tabbarVc, animated: true)
I have navigationController embedded VC(Viewcontroller) in storyboard 1 which is connected to storyboard reference of storyboard 2.
Now, I have VC2 which is again NavController Embedded in storyboard 2.
I am performing the following code :
let storyboard = UIStoryboard(name: "Settings", bundle: nil)
let vc = storyboard.instantiateViewController(withIdentifier: "setEdit") as? EditProfile
navigationController?.pushViewController(vc!, animated: true)
settings is storyboard 2, setEdit is ID from navigationController of the destination VC.
When I execute this code, It doesnt perform the presentation of new controller. Also, I have a custom segue class that transitions VCs from Right to Left.
when I use :
present(vc!, animated: true, completion: nil)
It just pushes the VC from bottom to top.
Now I am totally out of Ideas.
My query is:
How can I exactly implement custom segue from one storyboard to another, having navigation bar at the top.
When you use UINavigationController the transition is showed as you said from right to left (push), when you present a view controller modally the presentation style and the transition style are different. Now you cannot connect two navigation controllers, so I suggest to connect directly the controller in the settings storyboard without embedding it in another navigation controller. In settings storyboard you have to set your EditProfileVC as initial view controller and check its identifier and then you can push it from your first storyboard.
We are looking to change the way a user logs out of our app. In order to do that, we want to dismiss all the VCs below the current VC and put another VC on top as the root VC. Right now we are doing this which I believe does not dismiss any VC below from memory.
let viewController = storyboard?.instantiateViewController(withIdentifier: "SignIn")
if let unwrappedViewController = viewController {
self.present(unwrappedViewController, animated: true, completion: {})
}
The problem is that the VC that we want to put on top is not embedded in a Navigation Controller or tab bar controller. How would we dismiss the VCs and set the new VC as the main VC as if the user was opening the app for the first time without having previously logged in? We also do want the transition to be animated with whatever animation is normal for that event (modal animation is fine). I have read a bunch of different ways on doing it but I want to know which way is best practice and should be implemented specifically dismissing all VCs and putting a new VC that isn't in a Nav controller on top.
If you can access the UIWindow of the app, you can set its rootViewController property to your sign-in view controller, effectively removing all current view controllers and adding the sign-in view controller instead. Here's an example:
guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else { return }
// Should remove all subsequent view controllers from memory.
appDelegate.window?.rootViewController.dismiss(animated: true, completion: nil)
// Set the root view controller to a new instance of the sign in view controller.
appDelegate.window?.rootViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "SignIn")
My view hierarchy looks like image below:
My problem is I want to show VC1 when I click any button on VC3. Here is my code
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let vc = storyboard.instantiateViewControllerWithIdentifier("registerNavigation")
self.presentViewController(vc, animated: false, completion: nil)
but I got this warning "Warning: attempt to present ViewController whose view is not in the window hierarchy" and nothing happen. Please tell me, what did I do wrong?
If you want to show VC1 from VC3 the you not need to present it again because it is already loaded in navigation stack. you just need to dismiss or pop VC3 and VC2 from navigation stack. If you have presented it then dismiss and if you have pushed it then popped it.
Your warning's meaning : you are trying to presenting which is in the view hierarchy of navigation controller 1 but not in the view hierarchy of navigation controller 2.!!
Hope this will help :)
You are presenting to navigationController so use code like below.
let VC1 = self.storyboard!.instantiateViewControllerWithIdentifier("registerNavigation") as! ViewController
let navController = UINavigationController(rootViewController: VC1)
self.presentViewController(navController, animated:true, completion: nil)
I want to use a third-party library which implements a nice tabbar controller. But it does all the work programmatically, basically all it does is create two uiviewcontrollers and add them to a tabbarcontroller, and then instantiate an uinavigationcontroller with the tabbarcontroller. In the last step, it assigns the uinavigationcontroller to the rootviewcontroller of the window like the following:
self.window?.rootViewController = getNavigationController()
But I want to use this navigationcontroller in a place other than the rootviewcontroller of the window, say like I want to push from another view and goes to this navigationcontroller. How can I achieve that?
You can present it modally over your current navigation controller from your current viewcontroller
let vc = myNavigationControllerWithTabBarControllerInside() //change this to your navigation controller
self.navigationController.presentViewController(vc, animated: true, completion: nil)
Please verify, for your self.navigationController to not be nil. otherwise, use
self.presentViewController(vc, animated: true, completion: nil)