appdelete make tab bar vc root window swift 4

#APPDELETE MAKE TAB BAR VC ROOT WINDOW SWIFT 4 HOW TO#
#APPDELETE MAKE TAB BAR VC ROOT WINDOW SWIFT 4 FOR MAC#
#APPDELETE MAKE TAB BAR VC ROOT WINDOW SWIFT 4 CODE#

Lastly, it calls (_:willConnectTo:options:) in the SceneDelegate class. UIApplicationMain goes on to create a UISceneSession, UIWindowScene and an instance of the window scene’s delegate.Īfter that it checks if your app uses a storyboard and initializes the usual launching process (creating the window, assigning the first view controller’s view as its root view etc.)

#APPDELETE MAKE TAB BAR VC ROOT WINDOW SWIFT 4 CODE#

This is problematic for your code because, at this point, not even a window exists yet and thus your force unwrap crashes the app. However, in iOS 13 the order changes to the following:Īfter creating the application instance and assigning the app delegate class to its delegate property (I omitted that very first step above), UIApplicationMain immediately calls (_:didFinishLaunchingWithOptions:). This would be all well and good for your code, as the root view controller already exists when (_:didFinishLaunchingWithOptions:) is called. It calls (_:didFinishLaunchingWithOptions:) It then goes on to assign the view controller instantiated in step 1 as the window’s root view controller (that is the one your problematic line of code refers to), which retains it in memory. UIApplicationMain assigns the window (of type UIWindow) to the app delegate’s window property. UIApplicationMain looks to see whether your app uses a main storyboard if so, it instantiates the storyboard’s first view controller (that would be your UITabBarController I presume). New in iOS 13, your app can use scenes and scene-related classes and protocols (UISceneSession, UIScene, UIWindowScene, UIWindowSceneDelegate).”Īs far as I understand the author and the steps he outlines in the launching process, in iOS 12 and older launching used to proceed as follows: “Exactly how UIApplicationMain proceeds depends on what it discovers as it gets going. He writes that as of iOS 13 the app is launched with window scene support, which alters the order of assignments and, most importantly, the call to (_:didFinishLaunchingWithOptions:). I might have found a solution in Matt Neuburg’s book “Programming iOS 13” and on Andre Bancroft’s page.

Add the UIViewController instances to an array assigned to the ViewControllers property of the TabController.

Create UIViewController instances to add to the TabController.

Set the base class of TabController to UITabBarController.

To implement the UITabBarController we need to do the When the user selects a tab, the UITabBarController will take care of presenting the view for the The TabController class will contain the implementation of the UITabBarController that will manage an array of UIViewControllers. Name the file TabController as shown below: Next, add an empty class by selecting File > Newįile and choosing the General : Empty Class template.

#APPDELETE MAKE TAB BAR VC ROOT WINDOW SWIFT 4 FOR MAC#

Visual Studio for Mac and select a iOS > App > Empty Project template, Name the project TabbedApplication, as shown below: Select the File > New > Solution menu item in Gain a better understanding of how the application is constructed. Visual Studio for Mac, for this example, these instructions work from an empty project to Tabbed application walkthroughįor this walkthrough we’re going to create the following application:Īlthough there is already a tabbed application template available in

#APPDELETE MAKE TAB BAR VC ROOT WINDOW SWIFT 4 HOW TO#

To get an understanding of how to work with the UITabBarController, let’s walk through building a simpleĪpplication that uses one. Instance is accessible through the TabBarItem property of the The tabs are instances of the UITabBarItem class, which areĬontained in a UITabBar instance. The UITabBarController itself handles loading the properĬontroller and presenting its view based upon the selected tab.

Providing a tabbed user interface, via the UITabBar class, to allow a user to switch between controllers and their views.Ĭontrollers are added to the UITabBarController via its ViewControllers property, which is a UIViewControllerĪrray.Allowing multiple controllers to be added to it.The UITabBarController supports tabbed application development This page discusses both scenarios: when the tabs are at the root of the application view hierarchyĪnd also in the non- RootViewController scenario. Where an application first presents a login screen, followed by the tabbed However, with a bit of additional code, tabbed applications canĪlso be used in succession to some other initial screen, such as the scenario Usually, tabbed applications are built with the UITabBarController being the RootViewController of the The multi-screen management, allowing the application developer to focus on the Through the UITabBarController class, applications can easily include supportįor such multi-screen scenarios.

Screens can be accessed in no particular order. Tabbed applications are used in iOS to support user interfaces where multiple

Appdelete make tab bar vc root window swift 4