[objective-c] How to get root view controller?

Parameters of Method GET_ROOT_VIEW_CONTROLLER

Exceptions of Method GET_ROOT_VIEW_CONTROLLER

This method does not have any exceptions

«Alternate coding for Method Call with returning parameter

ld_RV_CONTROLLER = lo_CONTROL->GET_ROOT_CONTROLLER().

ld_RV_CONTROLLER = lo_CONTROL->GET_ROOT_CONTROLLER().

Method Type

Instance Method:   This is an Instance Method so needs to be instantiated first before you can access any of the methods. I.e. you need to create a local variable of TYPE ref to the class.

Method Type — Instance

This is an Instance Method so needs to be instantiated first before you can access any of the methods. I.e. you need to create a local variable of TYPE ref to the class.

• Importing parameters
• Exporting parameters
• Changing parameters
• Returning parameters
• Exceptions
• Coding Examples

The root view controller is simply the view controller that sits at the bottom of the navigation stack. You can access the navigation controller’s array of view controllers through its viewControllers property. To access the root view controller, we ask for the first item of the array of view controllers.

Below is documentation, parameters and attributes of ABAP Method GET_ROOT_VIEW_CONTROLLER within SAP class IWCI_IF_FPM_FLOORPLAN_COMP. There is also a number of example ABAP code snipts to help you use the functionality of this method.

This method is available within SAP systems depending on your version and release level, you can view further information by entering the class name IWCI_IF_FPM_FLOORPLAN_COMP into the relevant SAP transactions such as SE24 or SE80, and then selecting the method you are interested in.

Below is documentation, parameters and attributes of ABAP Method GET_ROOT_CONTROLLER within SAP class CL_EHPRC_IMDS_VIEW_CONTROL. There is also a number of example ABAP code snipts to help you implement this method.

This method is available within SAP systems depending on your version and release level and you can view further information by entering the class name CL_EHPRC_IMDS_VIEW_CONTROL into relevant SAP transactions such as SE24 or SE80, and then selecting the method you are interested in. Also check out the contributions below to view or add related hints, tips, example screen shots and any other information.

I need an instance of root view controller.

I tried those approaches:

UIViewController *rootViewController = (UIViewController*)[[[UIApplication sharedApplication] keyWindow] rootViewController];

Also when I try to get an array of controllers:

NSArray *viewControllers = self.navigationController.viewControllers;

It returns only one controller, but it isn’t my root view controller.

If I try to take from navigation controller:

UIViewController *root = (UIViewController*)[self.navigationController.viewControllers objectAtIndex:0];

Any ideas why? What else could I try to get an instance of my root view controller?

This question is related to

public String getURLBase(HttpServletRequest request) throws MalformedURLException {

    URL requestURL = new URL(request.getRequestURL().toString());
    String port = requestURL.getPort() == -1 ? "" : ":" + requestURL.getPort();
    return requestURL.getProtocol() + "://" + requestURL.getHost() + port;

}

@RequestMapping(value = "/someURL", method = RequestMethod.GET)
public ModelAndView doSomething(HttpServletRequest request) throws IOException{
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    // or this
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}

<c:set var="baseURL" value="${pageContext.request.localName}"/> //or ".localAddr"

<a data-hren="http://${baseURL}">Go Home</a>

Tags:

Spring Mvc

Base Url

The root view controller is simply the view controller that sits at the bottom of the navigation stack. You can access the navigation controller’s array of view controllers through its viewControllers property. To access the root view controller, we ask for the first item of the array of view controllers.

How do I get the root navigation controller in Swift?

How to get root view controller?

1. UIViewController *rootViewController = (UIViewController*)[[[UIApplication sharedApplication] keyWindow] rootViewController];
2. NSArray *viewControllers = self. navigationController. viewControllers;
3. UIViewController *root = (UIViewController*)[self. navigationController.

What is root view controller in Swift?

The root view controller provides the content view of the window. Assigning a view controller to this property (either programmatically or using Interface Builder) installs the view controller’s view as the content view of the window.

How do I change the root view controller in storyboard?

1) Remove Storyboards from app. plist file, 2) Uncheck option “isInitialViewController” from Storyboards which is checked in case of Tab Bar controller because its a root ViewController , 3) Add this code in appDelegate. m file.

The root view controller is simply the view controller that sits at the bottom of the navigation stack. You can access the navigation controller’s array of view controllers through its viewControllers property. To access the root view controller, we ask for the first item of the array of view controllers.

What is the root view controller?

How do I set root view controller programmatically?

1. Set Application Root View Controller Programmatically In Xcode 11 Example.

1. Create an iOS Single View App in Xcode 11.
2. Then you can see the SceneDelegate.
3. Open SceneDelegate.
4. Edit the SceneDelegate.
5. SceneDelegate.

How do I get navigation controller from storyboard?

Go to the Storyboard and delete the View Controller. Open the Object Library and drag a Navigation Controller to the Storyboard. Select the Navigation Controller and go to The Attribute inspector. In the View Controller section check the “Is Initial View Controller” checkbox.

How do I add a navigation controller to my storyboard?

Create a Navigation Controller Open Main. storyboard and select the Reminder List View Controller scene. Click the Embed In button and choose Navigation Controller. Because the embedded view controller was the initial view controller of the storyboard, the navigation controller becomes the initial view controller.

YourViewController *rootController =
    (YourViewController *)
        [self.navigationController.viewControllers objectAtIndex: 0];

UIViewController *controller = [UIApplication sharedApplication].keyWindow.rootViewController;

let viewController = UIApplication.sharedApplication().keyWindow?.rootViewController

let viewController = UIApplication.shared.keyWindow?.rootViewController

YourViewController *rootController = (YourViewController*)[[(YourAppDelegate*)
                                   [[UIApplication sharedApplication]delegate] window] rootViewController];

let appDelegate  = UIApplication.sharedApplication().delegate as AppDelegate
let viewController = appDelegate.window!.rootViewController as YourViewController

let appDelegate  = UIApplication.shared.delegate as! AppDelegate
let viewController = appDelegate.window!.rootViewController as! YourViewController

let viewController = UIApplication.shared.keyWindow!.rootViewController as! YourViewController

let viewController = UIApplication.shared.windows.first!.rootViewController as! YourViewController

Tags:

Objective C

Swift

Uiviewcontroller

Uinavigationcontroller

Ios5

YourViewController *rootController =
    (YourViewController *)
        [self.navigationController.viewControllers objectAtIndex: 0];

UIViewController *controller = [UIApplication sharedApplication].keyWindow.rootViewController;

let viewController = UIApplication.sharedApplication().keyWindow?.rootViewController

let viewController = UIApplication.shared.keyWindow?.rootViewController

YourViewController *rootController = (YourViewController*)[[(YourAppDelegate*)
                                   [[UIApplication sharedApplication]delegate] window] rootViewController];

let appDelegate  = UIApplication.sharedApplication().delegate as AppDelegate
let viewController = appDelegate.window!.rootViewController as YourViewController

let appDelegate  = UIApplication.shared.delegate as! AppDelegate
let viewController = appDelegate.window!.rootViewController as! YourViewController

let viewController = UIApplication.shared.keyWindow!.rootViewController as! YourViewController

let viewController = UIApplication.shared.windows.first!.rootViewController as! YourViewController

Tags:

Objective C

Swift

Uiviewcontroller

Uinavigationcontroller

Ios5

Links to Related Class(s)

How do I join a scene delegate?

Once you have the scene, you can access its delegate. This can be called from any view or view controller to get its scene. But note that you can only get the scene from a view controller only after viewDidAppear has been called at least once.

How do I get rootViewController of Uinavigationcontroller?

How do I change the root view controller in Swift?

1. @IBAction func switchButtonPresed(sender: AnyObject.
2. // switch root view controllers in AppDelegate.
3. let appDelegate = UIApplication. sharedApplication. delegate as! AppDelegate.
4. appDelegate. switchViewControllers()

What is UIWindow in Swift?

Where is the root view controller in Swift?

Here is a good way to approach it. This example places a navigation controller as the root view controller, and puts the view controller of your choice within it at the bottom of the navigation stack, ready for you to push whatever you need to from it.

Which is the first view controller in the navigation stack?

A navigation controller object manages its child view controllers using an ordered array, known as the navigation stack. The first view controller in the array is the root view controller and represents the bottom of the stack.

How to change the view of the navigation controller?

Ctrl + drag from the Navigation Controller to the View Controller and select the “root view controller” segue. Select the View Controller’s view and Go to the Attributes inspector. Change the background to light grey. Select the View Controller.

How do I get the root view controller in swift 5?

1. Objective-C. YourViewController *rootController = (YourViewController*)[[(YourAppDelegate*) [[UIApplication sharedApplication]delegate] window] rootViewController];
2. Swift. let appDelegate = UIApplication.
3. Swift 3. let appDelegate = UIApplication.
4. Swift 4 & 4.2.
5. Swift 5 & 5.1 & 5.2.

How do I push a new ViewController?

Navigation Controller Push View Controller

1. Create the sample single view application.
2. Add a new file -> Objective-C Class with XIB for user interface (ViewController2).
3. Add a button into ViewController. xib and control click the button to ViewController.
4. Go to the newly made IBAction in ViewController.

Questions with uinavigationcontroller tag

• How to enable back/left swipe gesture in UINavigationController after setting leftBarButtonItem?
• How to hide a navigation bar from first ViewController in Swift?
• Execute action when back bar button of UINavigationController is pressed
• Programmatically navigate to another view controller/scene
• How to force view controller orientation in iOS 8?
• presenting ViewController with NavigationViewController swift
• How to Navigate from one View Controller to another using Swift
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• How to check if a view controller is presented modally or pushed on a navigation stack?
• Trying to handle «back» navigation button action in iOS
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• How to get root view controller?
• Removing viewcontrollers from navigation stack
• Programmatically get height of navigation bar
• back button callback in navigationController in iOS
• Navigation bar show/hide
• iPhone: Setting Navigation Bar Title
• How to change the Push and Pop animations in a navigation based app
• How do I get the RootViewController from a pushed controller?
• How to add a right button to a UINavigationController?
• Setting action for back button in navigation controller
• iPhone hide Navigation Bar only on first page
• How to hide ‘Back’ button on navigation bar on iPhone?

Solution 3

YourViewController *rootController =
    (YourViewController *)
        [self.navigationController.viewControllers objectAtIndex: 0];

The code in the answer above returns UINavigation controller (if you have it) and if this is what you need, you can use self.navigationController.

Solution 2

UIViewController *controller = [UIApplication sharedApplication].keyWindow.rootViewController;

let viewController = UIApplication.sharedApplication().keyWindow?.rootViewController

let viewController = UIApplication.shared.keyWindow?.rootViewController

How do I hide items in navigation?

Way 1: Touch “Settings” -> “Display” -> “Navigation bar” -> “Buttons” -> “Button layout”. Choose the pattern in “Hide navigation bar” -> When the app opens, the navigation bar will be automatically hidden and you can swipe up from the bottom corner of the screen to show it.

The answer is

if you are trying to access the rootViewController you set in your appDelegate. try this:

YourViewController *rootController = (YourViewController*)[[(YourAppDelegate*)
                                   [[UIApplication sharedApplication]delegate] window] rootViewController];

let appDelegate  = UIApplication.sharedApplication().delegate as AppDelegate
let viewController = appDelegate.window!.rootViewController as YourViewController

let appDelegate  = UIApplication.shared.delegate as! AppDelegate
let viewController = appDelegate.window!.rootViewController as! YourViewController

Swift 4 & 4.2

let viewController = UIApplication.shared.keyWindow!.rootViewController as! YourViewController

Swift 5 & 5.1 & 5.2

let viewController = UIApplication.shared.windows.first!.rootViewController as! YourViewController

UIViewController *controller = [UIApplication sharedApplication].keyWindow.rootViewController;

let viewController = UIApplication.sharedApplication().keyWindow?.rootViewController

let viewController = UIApplication.shared.keyWindow?.rootViewController

YourViewController *rootController =
    (YourViewController *)
        [self.navigationController.viewControllers objectAtIndex: 0];

The code in the answer above returns UINavigation controller (if you have it) and if this is what you need, you can use self.navigationController.

Unless you have a good reason, in your root controller do this:

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(onTheEvent:)
                                             name:@"ABCMyEvent"
                                           object:nil];

And when you want to notify it:

[[NSNotificationCenter defaultCenter] postNotificationName:@"ABCMyEvent"
                                                object:self];                

let rootViewController = UIApplication.shared.keyWindow?.rootViewController

Swift way to do it, you can call this from anywhere, it returns optional so watch out about that:

/// EZSwiftExtensions - Gives you the VC on top so you can easily push your popups
var topMostVC: UIViewController? {
    var presentedVC = UIApplication.sharedApplication().keyWindow?.rootViewController
    while let pVC = presentedVC?.presentedViewController {
        presentedVC = pVC
    }

    if presentedVC == nil {
        print("EZSwiftExtensions Error: You don't have any views set. You may be calling them in viewDidLoad. Try viewDidAppear instead.")
    }
    return presentedVC
}

Its included as a standard function in:

Swift 3: Chage ViewController withOut Segue and send AnyObject
Use: Identity MainPageViewController on target ViewController

let mainPage = self.storyboard?.instantiateViewController(withIdentifier: "MainPageViewController") as! MainPageViewController

var mainPageNav = UINavigationController(rootViewController: mainPage)

self.present(mainPageNav, animated: true, completion: nil)

or if you want to Change View Controller and send Data

let mainPage = self.storyboard?.instantiateViewController(withIdentifier: "MainPageViewController") as! MainPageViewController

let dataToSend = "**Any String**" or  var ObjectToSend:**AnyObject** 

mainPage.getData = dataToSend 

var mainPageNav = UINavigationController(rootViewController: mainPage)

self.present(mainPageNav, animated: true, completion: nil)  

Solution 5

Unless you have a good reason, in your root controller do this:

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(onTheEvent:)
                                             name:@"ABCMyEvent"
                                           object:nil];

And when you want to notify it:

[[NSNotificationCenter defaultCenter] postNotificationName:@"ABCMyEvent"
                                                object:self];                

Comments

• I need an instance of root view controller.

  I tried those approaches:

  UIViewController *rootViewController = (UIViewController*)[[[UIApplication sharedApplication] keyWindow] rootViewController];
  

  Returns: null:

  Also when I try to get an array of controllers:

  NSArray *viewControllers = self.navigationController.viewControllers;
  

  It returns only one controller, but it isn’t my root view controller.

  If I try to take from navigation controller:

  UIViewController *root = (UIViewController*)[self.navigationController.viewControllers objectAtIndex:0];
  

  Returns: null:

  Any ideas why? What else could I try to get an instance of my root view controller?

• Is there any way to have two controllers assigned in this manner so that you can pull data from both to the watch?

• This should be the top answer. +1 The other answers will not work if you need to reference the root view controller from a different framework that your main app is dependent on.

• You are the best dude 🙂

• This is a lifesaver. Thank you! Took me months to find this piece of delicious code!

• It’s worth pointing out that keyWindow was deprecated in iOS13

• AVPictureInPictureController or AVPlayerViewController will create new window which class is PGHostedWindow and add it to windows array, Therefore, using the first window may cause a crash

Returning Parameters

RV_CONTROLLER » Controller on topmost level TYPE REF TO CL_EHPRC_IMDS_VIEW_CONTROL

Example ABAP coding

DATA: lo_class TYPE REF TO IWCI_IF_FPM_FLOORPLAN_COMP.
DATA: lv_RO_VIEW_CONTROLLER TYPE IF_WD_VIEW_CONTROLLER,
lv_other TYPE c.

CALL METHOD lo_class=>GET_ROOT_VIEW_CONTROLLER(
RECEIVING
RO_VIEW_CONTROLLER = lv_RO_VIEW_CONTROLLER )

«Alternate coding for Method Call with returning parameter
lv_RO_VIEW_CONTROLLER = lo_class=>GET_ROOT_VIEW_CONTROLLER( ).

How to access root view controller in iOS 13?

A new SceneDelegate was introduced for Storyboard-based apps in iOS 13, and with it came some changes in how you’re able to access your app’s root view controller at app launch. AppDelegate Swift file used to be where code landed for accessing your app’s rootViewController:

How do I open the view controller scene?

4 Answers. Look for a button in the bottom-left corner of the canvas where you are building your views. Click that and the Document Outline should open. I had the same problem and I clicked View Controller Scene from the top like you have, then Storyboard Entry Point and tada, it appeared!

How to change the view of the navigation controller?

Ctrl + drag from the Navigation Controller to the View Controller and select the “root view controller” segue. Select the View Controller’s view and Go to the Attributes inspector. Change the background to light grey. Select the View Controller.

Which is the first view controller in the navigation stack?

A navigation controller object manages its child view controllers using an ordered array, known as the navigation stack. The first view controller in the array is the root view controller and represents the bottom of the stack.

Select the Navigation Controller and go to The Attribute inspector. In the View Controller section check the “Is Initial View Controller” checkbox. The Navigation Controller will automatically contain a Table View Controller, delete this and drag a View Controller to the storyboard.

How to programmatically navigate to another view in iOS?

It will just take complete screen. For this case you have to create another navigation controller and add your nextViewController as root for this and present this new navigationController. Another way is to just push the view controller.

Solution 4

For Swift 5 and later, I recommend use this method:

UIApplication.shared.windows.last?.rootViewController

Use .last will return top view Controller is active.

.first sometimes doesn’t work with libraries that require a window on top & actived.

For example: Admob . I have the ad not showing and find that I am calling the hidden window underneath when using sheet or fullscreenCover.

NOTE: View want to display ads required in NavigationView, if not, ads will be not run.

I hope it is useful.

How do I get back to rootViewController in Swift?

To go back to root view controller, you can simply call a line of code and your work will be done. And if you have the splash screen and after that the login screen and you want to go to login screen you can simply append presentedviewcontroller in the above code.

How do I navigate to ViewController from AppDelegate Swift?

Navigate From AppDelegate. swift to a Different ViewController

1. Create an instance of UIStoryboard, let mainStoryboard:UIStoryboard = UIStoryboard(name: “Main”, bundle: nil)
2. Instantiate View Controller with Identifier, HomeViewController.
3. Set the Root View Controller of your app’s window to a different one.

Which is the root view controller in uinavigationcontroller?

If you look in the split view controller, you’ll see the view controller has a relationship segue called detail view controller: Table View Controller: This is the root view controller of the master UINavigationController. It’ll eventually display the list of monsters.

How to remove the rootviewcontroller from the view hierarchy?

In an effort to remove every UIViewControllerfrom the view hierarchy and memory graph, the code completely ignores the presentation. The presentand dismisscalls are happening independently and on separate transition contexts. Let’s break it down. The DoneViewControlleris presenting, modally, the MainViewController.

Which is the root view of the Master View Controller?

Navigation Controller: This UINavigationController will be the root view of your master view controller. This is the left pane of the split view when on iPad or when in landscape on a larger iPhone such as the iPhone 8 Plus. In the split view controller, you’ll see the navigation controller has a relationship segue called master view controller.

How do I present a navigation controller in Swift?

Present ViewController in NavigationController

1. // Register Nib.
2. let newViewController = CustomSignupViewController(nibName: “CustomSignupViewController”, bundle: nil)
3. let navigationController = UINavigationController(rootViewController: newViewController)
4. // Present View “Modally”
5. self.

How to get the root view controller of a navigation controller?

You can access the top view controller through the topViewController computed property, but the UINavigationController class doesn’t offer an API that easily lets you access the root controller. But it’s easy to do. The root view controller is simply the view controller that sits at the bottom of the navigation stack.

Can a navigation controller be used as a view controller?

Do you have to pop the navigation controller off the stack?

How do I install a navigation controller on my computer?

Install it directly as a window’s root view controller. Install it as the view controller of a tab in a tab bar interface. Present it modally from another view controller. In the first three scenarios, the navigation controller provides a crucial part of your basic interface and stays in place until the app exits.

Example ABAP coding

DATA:
ld_RV_CONTROLLER TYPE REF TO CL_EHPRC_IMDS_VIEW_CONTROL.

DATA: lo_CONTROL TYPE REF TO CL_EHPRC_IMDS_VIEW_CONTROL .

CALL METHOD lo_CONTROL->GET_ROOT_CONTROLLER(

RECEIVING

RV_CONTROLLER = ld_RV_CONTROLLER ).

Questions with uiviewcontroller tag

• How to set Status Bar Style in Swift 3
• UIView touch event in controller
• How to lock orientation of one view controller to portrait mode only in Swift
• Programmatically navigate to another view controller/scene
• Adding a view controller as a subview in another view controller
• Changing the Status Bar Color for specific ViewControllers using Swift in iOS8
• Get top most UIViewController
• Instantiate and Present a viewController in Swift
• How to check if a view controller is presented modally or pushed on a navigation stack?
• Add a UIView above all, even the navigation bar
• Display UIViewController as Popup in iPhone
• iOS: present view controller programmatically
• How to call a View Controller programmatically?
• modal View controllers — how to display and dismiss
• Dismissing a Presented View Controller
• How to get root view controller?
• Get the current displaying UIViewController on the screen in AppDelegate.m
• Move UIView up when the keyboard appears in iOS
• How can I switch views programmatically in a view controller? (Xcode, iPhone)
• Programmatically set the initial view controller using Storyboards
• Removing viewcontrollers from navigation stack
• presentViewController and displaying navigation bar
• Reloading a ViewController
• Storyboard — refer to ViewController in AppDelegate
• How to find topmost view controller on iOS
• Looking to understand the iOS UIViewController lifecycle
• Passing data between view controllers
• iOS — Calling App Delegate method from ViewController
• How to tell if UIViewController’s view is visible
• UIViewController viewDidLoad vs. viewWillAppear: What is the proper division of labor?
• Present and dismiss modal view controller
• How to add an UIViewController’s view as subview
• Given a view, how do I get its viewController?
• Get to UIViewController from UIView?

Where can I find the root view controller?

You can access the navigation controller’s array of view controllers through its viewControllers property. To access the root view controller, we ask for the first item of the array of view controllers. Each view controller in the array is a child view controller and the navigation controller is the parent view controller.

What does the rootviewcontroller do in UIWindow?

The RootViewControllerhad its Container View as a subview rather than being the view. Though technically is allowed, in this case it is not a requirement. The RootViewController.viewDidLayoutSubviews()used to call self.transition(from:to:)which in certain layouts it leads to an unwanted animation.

When does the rootviewcontroller revert to registerview controller?

How to remove the rootviewcontroller from the view hierarchy?

In an effort to remove every UIViewControllerfrom the view hierarchy and memory graph, the code completely ignores the presentation. The presentand dismisscalls are happening independently and on separate transition contexts. Let’s break it down. The DoneViewControlleris presenting, modally, the MainViewController.

How do I present UIViewController?

1. // Register Nib.
2. let newViewController = NewViewController(nibName: “NewViewController”, bundle: nil)
3. // Present View “Modally”
4. self. present(newViewController, animated: true, completion: nil)

How do I get rootViewController of UINavigationController?

How to get root view controller?

1. UIViewController *rootViewController = (UIViewController*)[[[UIApplication sharedApplication] keyWindow] rootViewController];
2. NSArray *viewControllers = self. navigationController. viewControllers;
3. UIViewController *root = (UIViewController*)[self. navigationController.

How do I join a scene delegate?

Once you have the scene, you can access its delegate. This can be called from any view or view controller to get its scene. But note that you can only get the scene from a view controller only after viewDidAppear has been called at least once.

How do you dismiss a segue?

Connect a Triggering Object to the Exit Control Select one of the action methods to complete the unwind segue. You only select the action method, not a specific view controller. To be displayed after the dismissal, a parent view controller must implement the method you select.

What is present Modally Swift?

How do I get to rootViewController in AppDelegate?

How to get root view controller?

1. Objective-C YourViewController *rootController = (YourViewController*)[[(YourAppDelegate*) [[UIApplication sharedApplication]delegate] window] rootViewController];
2. Swift let appDelegate = UIApplication.sharedApplication().delegate as AppDelegate let viewController = appDelegate.window!.

Which is the first view controller in the navigation stack?

A navigation controller object manages its child view controllers using an ordered array, known as the navigation stack. The first view controller in the array is the root view controller and represents the bottom of the stack.

What kind of controller is a navigation controller?

A navigation controller is a container view controller—that is, it embeds the content of other view controllers inside of itself. You access a navigation controller’s view from its view property.

Is the toolbar hidden in the navigation controller?

The navigation toolbar is hidden by default but you can show it for your navigation interface by calling the setToolbarHidden (_:animated:) method of your navigation controller object.

How are navigation view controllers used in Swift?

Navigation view controllers are stack based. The newest view controller is the visible one. It is on top of the last one we saw. If you are not familiar with the stack data structure, it is useful to understand stacks and their nomenclature a little better. Stacks work a lot like a deck of cards that are face up. You can only see the top card.

How do I change the root view in SwiftUI?

1. Step 1: Create an AppState ObservableObject. import SwiftUI.
2. Step 2: Create an instance of AppState and add in contentView in SceneDelegate. func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
3. Step 3: Code of ContentView. swift.

What is Makekeyandvisible?

Discussion. This is a convenience method to show the current window and position it in front of all other windows at the same level or lower. If you only want to show the window, change its isHidden property to false .

How do I delegate without scene?

1. Completely remove the “Application Scene Manifest” entry from Info. plist.
2. If there is a scene delegate class, remove it.
3. If there are any scene related methods in your app delegate, remove those methods.
4. If missing, add the property var window: UIWindow? to your app delegate.

How to get the root view controller of a navigation controller?

You can access the top view controller through the topViewController computed property, but the UINavigationController class doesn’t offer an API that easily lets you access the root controller. But it’s easy to do. The root view controller is simply the view controller that sits at the bottom of the navigation stack.

Where does the view controller go on the stack?

The object in the viewController parameter becomes the top view controller on the navigation stack. Pushing a view controller causes its view to be embedded in the navigation interface. If the animated parameter is true, the view is animated into position; otherwise, the view is simply displayed in its final location.

Solution 1

if you are trying to access the rootViewController you set in your appDelegate. try this:

YourViewController *rootController = (YourViewController*)[[(YourAppDelegate*)
                                   [[UIApplication sharedApplication]delegate] window] rootViewController];

let appDelegate  = UIApplication.sharedApplication().delegate as AppDelegate
let viewController = appDelegate.window!.rootViewController as YourViewController

let appDelegate  = UIApplication.shared.delegate as! AppDelegate
let viewController = appDelegate.window!.rootViewController as! YourViewController

Swift 4 & 4.2

let viewController = UIApplication.shared.keyWindow!.rootViewController as! YourViewController

Swift 5 & 5.1 & 5.2

let viewController = UIApplication.shared.windows.first!.rootViewController as! YourViewController

What is root view controller in Swift?

The root view controller provides the content view of the window. Assigning a view controller to this property (either programmatically or using Interface Builder) installs the view controller’s view as the content view of the window.

How do I hide the Navigation bar in HTML?

CSS – Hide Nav Bar & Footer

1. add id = ‘nav-bar’ inside nav tag and in your css – #nav-bar{display:none;} – user4520208 Jul 2 ’16 at 4:07.
2. Have you tried applying the CSS styling using Chrome DevTools (or your browser’s equivalent live CSS editor)? Does it work from there? –

What happens when you push a view controller?

Pushing a view controller causes its view to be embedded in the navigation interface. If the animated parameter is true, the view is animated into position; otherwise, the view is simply displayed in its final location.

What does pushviewcontroller do on an iPhone?

pushViewController(_:animated:) Pushes a view controller onto the receiver’s stack and updates the display.

Is the navigation controller automatically presented in UIViewController?

UINavigationController is not automatically presented in UIViewController. This is what you should see in Interface Builder. Files owner has view outlet to Navigation controller and from navigation controller is outlet to actual view;