UISplitViewController within UITabbarController Swift - ios

Okay i have a Universal single view application with a UITabbarController as the initial ViewController. i have a UISplitViewController as an item in one of the tabs. the SplitViewController has a navigationController as its master segue, which has a viewController with a uitableView in it and if you click a cell it "shows" the detail view (I've tried the show detail segue also). the splitViewControllers detail view controller segue goes to the detail view controller.
my problem is when i go to the tab with the splitViewController in it it shows the detail first and not the master(same for both ipad and iphone). i have spent hours reading and watching different tutorials and looking at questions on here and cant find a solution.
code i have tried(in a custom split viewcontroller class and viewcontroller with the tableView class):
func splitViewController(splitViewController: UISplitViewController, collapseSecondaryViewController secondaryViewController: UIViewController, ontoPrimaryViewController primaryViewController: UIViewController) -> Bool {
return true
}
override func viewWillAppear(animated: Bool) {
splitViewController?.delegate = self
self.splitViewController!.delegate = self;
self.splitViewController!.preferredDisplayMode = UISplitViewControllerDisplayMode.AllVisible
if UIDevice.currentDevice().userInterfaceIdiom == .Phone {
if let con = self.splitViewController {
con.preferredDisplayMode = .PrimaryOverlay
print("phone")
//^this code doesnt run when i run it on my iphone
}
} else if UIDevice.currentDevice().userInterfaceIdiom == .Pad {
if let spec = self.splitViewController {
spec.preferredDisplayMode = .AllVisible
}
} else {
if let tit = self.splitViewController {
tit.preferredDisplayMode = .Automatic
}
}
}
//controller with tableView class declaration
class OutfitTable : UIViewController, UITableViewDelegate, UITableViewDataSource, UISplitViewControllerDelegate {
//custom splitViewController class declaration
class SplitViewController: UISplitViewController, UISplitViewControllerDelegate
screenshot of main storyboard:
im sorry if this is unnecessarily descriptive i just want to make sure i get all the information out there.
Anything helps. Thank You in advance

Related

getting current active viewController in UITabBarControllerDelegate

I want to implement a scrollToTop method on all of my viewControllers in my UITabBarController. The following is a method in the UITabBarControllerDelegate and triggers, when I select a tab.
The problem is, that I only want to scroll to the top of the viewController, when the viewController is active. So that the user can switch tabs without losing the scroll position, but when he touches the tab in the tabBar of the currently active tab, it should scroll to the top.
func tabBarController(_ tabBarController: UITabBarController, didSelect viewController: UIViewController) {
if viewControllerThatIsCurrentlyActiveInTabBar == viewController {
scrollToTop()
}
}
Basically, I need that condition of the if statement above.
I tried: viewController.isViewLoaded, tabBarController.selectedViewController == viewController, viewController.isBeingPresented. None of those conditions worked. It would either not trigger scrollToTop() or it would trigger always so that you lose the scroll position when you change tabs because it would immediately scroll to the top.
You need to make a code in should select instead of didselect. As it is unable to find the previous controller after selection. below is the example code for it.
func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
if tabBarController.selectedViewController == viewController {
print("Same viewcontroller")
}
return true
}
Can you use below extension for getting top viewcontroller of tabbarcontroller.
extension UIViewController {
var top: UIViewController? {
if let controller = self as? UINavigationController {
return controller.topViewController?.top
}
if let controller = self as? UISplitViewController {
return controller.viewControllers.last?.top
}
if let controller = self as? UITabBarController {
return controller.selectedViewController?.top
}
if let controller = presentedViewController {
return controller.top
}
return self
}
}
You can use above extension below
if let rootViewController = UIApplication.top() {
//do with Active view controller
}

UISplitViewController will not correctly collapse at launch on iPad iOS 13

I am transitioning my app to iOS 13, and the UISplitViewController collapses onto the detail view, rather than the master at launch — only on iPad. Also, the back button is not shown - as if it is the root view controller.
My app consists of a UISplitViewController which has been subclassed, conforming to UISplitViewControllerDelegate. The split view contains two children — both UINavigationControllers, and is embedded in a UITabBarController (subclassed TabViewController)
In the split view viewDidLoad, the delegate is set to self and preferredDisplayMode is set to .allVisible.
For some reason, the method splitViewController(_:collapseSecondary:onto:) not being called.
In iOS 12 on iPhone and iPad, the method splitViewController(_:collapseSecondary:onto:) is correctly called at launch, in between application(didFinishLaunchingWithOptions) and applicationDidBecomeActive.
In iOS 13 on iPhone, the method splitViewController(_:collapseSecondary:onto:) is correctly called at launch, in between scene(willConnectTo session:) and sceneWillEnterForeground.
In iOS 13 on iPad, however, if the window has compact width at launch e.g. new scene created as a split view, the splitViewController(_:collapseSecondary:onto:) method is not called at all. Only when expanding the window to regular width, and then shrinking is the method called.
class SplitViewController: UISplitViewController, UISplitViewControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
self.delegate = self
preferredDisplayMode = .allVisible
}
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool {
print("Split view controller function")
guard let secondaryAsNavController = secondaryViewController as? UINavigationController else { return false }
guard let topAsDetailController = secondaryAsNavController.topViewController as? DetailViewController else { return false }
if topAsDetailController.passedEntry == nil {
return true
}
return false
}
}
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
// Setup split controller
let tabViewController = self.window!.rootViewController as! TabViewController
let splitViewController = tabViewController.viewControllers![0] as! SplitViewController
let navigationController = splitViewController.viewControllers[splitViewController.viewControllers.count-1] as! UINavigationController
navigationController.topViewController!.navigationItem.leftBarButtonItem = splitViewController.displayModeButtonItem
navigationController.topViewController!.navigationItem.leftBarButtonItem?.tintColor = UIColor(named: "Theme Colour")
splitViewController.preferredDisplayMode = .allVisible
}
class AppDelegate: UIResponder, UIApplicationDelegate {
var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
if #available(iOS 13.0, *) {
} else {
let tabViewController = self.window!.rootViewController as! TabViewController
let splitViewController = tabViewController.viewControllers![0] as! SplitViewController
let navigationController = splitViewController.viewControllers[splitViewController.viewControllers.count-1] as! UINavigationController
navigationController.topViewController!.navigationItem.leftBarButtonItem = splitViewController.displayModeButtonItem
navigationController.topViewController!.navigationItem.leftBarButtonItem?.tintColor = UIColor(named: "Theme Colour")
splitViewController.preferredDisplayMode = .allVisible
}
return true
}
It stumps me why the method is being called in iPhone, but not in iPad! I am a new developer and this is my first post, so apologies if my code doesn't give enough detail or is not correctly formatted!
For some reason on iOS 13 specifically on the iPad in compact traitCollections the call to the delegate to see if it should collapse is happening BEFORE viewDidLoad is called on the UISplitViewController and so when it makes that call, your delegate is not set, and the method never gets called.
If you're creating your splitViewController programmatically this is an easy fix, but if you're using Storyboards not so much. You can work around this by setting your delegate in awakeFromNib() instead of viewDidLoad()
Using your example from the original post, a sample of code would be as follows
class SplitViewController: UISplitViewController, UISplitViewControllerDelegate {
override func awakeFromNib() {
super.awakeFromNib()
delegate = self
preferredDisplayMode = .allVisible
}
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool {
return true
}
}
You'll also want to make sure whatever logic you're using in the collapseSecondary function isn't referencing variables that aren't yet populated since viewDidLoad hasn't been called yet.
I have an Xcode project - now for iOS 13 - that uses a tab bar controller with relationships to five split view controllers, each with their own master detail (table) views and controllers.
Previously - iOS 12.x and earlier, in fact back when I was writing Objective-C - my split view controller delegate was set in code of the master view controller of each (parent) split view controller - I set the delegate in the subclassed UITableViewController's viewDidLoad method. This worked successfully for years on both iPhone and iPad.
e.g.
class MasterViewController: UITableViewController, UISplitViewControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
splitViewController?.preferredDisplayMode = UISplitViewController.DisplayMode.allVisible
splitViewController?.delegate = self
...
}
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool {
...
}
}
To be clear, I have not subclassed the tab bar controller or the split view controllers.
With the release of Xcode 11 and iOS 13, the split view controller delegate methods in the master view controllers were no longer called.
To be clear, for iOS 13, regardless of device or simulator, splitViewController(_:collapseSecondary:onto:) is not called (tested using breakpoints), with the resulting behaviour:
iPhone - detail view controller is presented when app is run on device or simulator.
iPad - detail view controller is presented when app is run on device or simulator, without a back button, so there is no obvious mechanism to "escape" the detail view. The only user workaround I found that resolves this problem, is to change device orientation. Following that, the split view controller behaves as expected.
I thought this may have something to do with the new class SceneDelegate.
So I retrofitted a custom SceneDelegate class into my test projects and then my primary project.
I have the custom SceneDelegate class working perfectly. I know this because I successfully set a window?.tintColor in the scene(_:willConnectTo:options:) method.
However the problems with split view controller delegates continued.
I logged feedback to Apple and this is their edited response...
...the problem is that you are setting the UISplitViewController’s delegate
in an override of viewDidLoad. It’s possible that the
UISplitViewController is deciding to collapse before anything causes
its view to be loaded. When it does that, it checks its delegate, but
since the delegate is still nil since you haven’t set it yet, your
code wouldn’t be called.
Since views are loaded on demand, the timing of viewDidLoad can be
unpredictable. In general it’s better to set up things like view
controller delegates earlier. Doing it in scene(willConnectTo:
session) is likely to work better.
This advice helped me a lot.
In my custom SceneDelegate class I added the following code into the scene(_:willConnectTo:options:) method...
class SceneDelegate: UIResponder, UIWindowSceneDelegate, UISplitViewControllerDelegate {
var window: UIWindow?
func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
guard let window = window else { return }
guard let tabBarController = window.rootViewController as? UITabBarController else { return }
guard let splitViewController = tabBarController.viewControllers?.first as? UISplitViewController else { return }
splitViewController.delegate = self
splitViewController.preferredDisplayMode = UISplitViewController.DisplayMode.allVisible
}
...
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool {
...
}
}
This code worked for both iPhone and iPad, but perhaps obviously for only the first split master detail view controller combination.
I changed the code to attempt to achieve this success for all five split view controllers...
guard let window = window else { return }
guard let tabBarController = window.rootViewController as? UITabBarController else { return }
guard let splitViewControllers = tabBarController.viewControllers else { return }
for controller in splitViewControllers {
guard let splitViewController = controller as? UISplitViewController else { return }
splitViewController.delegate = self
splitViewController.preferredDisplayMode = UISplitViewController.DisplayMode.allVisible
}
This code works too... almost...
My check for whether to return true for collapseSecondary is based on a unique value - a computed property - from each of the five detail view controllers. Because of this unique check, it seemed difficult to determine this in my custom SceneDelegate class, so in my custom SceneDelegate class, I wrote the following code instead...
guard let window = window else { return }
guard let tabBarController = window.rootViewController as? UITabBarController else { return }
guard let splitViewControllers = tabBarController.viewControllers else { return }
for controller in splitViewControllers {
guard let splitViewController = controller as? UISplitViewController else { return }
guard let navigationController = splitViewController.viewControllers.first else { return }
guard let masterViewController = navigationController.children.first else { return }
splitViewController.delegate = masterViewController as? UISplitViewControllerDelegate
splitViewController.preferredDisplayMode = UISplitViewController.DisplayMode.allVisible
}
...and then made each detail view controller conform to UISplitViewControllerDelegate.
e.g.
class MasterViewController: UITableViewController, UISplitViewControllerDelegate {
override func viewDidLoad() {
super.viewDidLoad()
// the following two calls now in the scene(_:willConnectTo:options:) method...
// splitViewController?.preferredDisplayMode = UISplitViewController.DisplayMode.allVisible
// splitViewController?.delegate = self
...
}
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool {
...
}
}
So far so good, each of the five split view controllers collapses the detail view at app startup, for both iPhone and iPad.
Well, I think the answer should cover the iOS14 now.
If you find the delegate method is not be called.
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool {
...
}
maybe you should consider to use iOS14's one.
#available(iOS 14.0, *)
func splitViewController(_ svc: UISplitViewController, topColumnForCollapsingToProposedTopColumn proposedTopColumn: UISplitViewController.Column) -> UISplitViewController.Column {
return .primary
}
You need to add this in the function "scene" in the class "SceneDelegate":
splitViewController.delegate = self
for example:
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
// Setup split controller
let tabViewController = self.window!.rootViewController as! TabViewController
let splitViewController = tabViewController.viewControllers![0] as! SplitViewController
let navigationController = splitViewController.viewControllers[splitViewController.viewControllers.count-1] as! UINavigationController
navigationController.topViewController!.navigationItem.leftBarButtonItem = splitViewController.displayModeButtonItem
navigationController.topViewController!.navigationItem.leftBarButtonItem?.tintColor = UIColor(named: "Theme Colour")
splitViewController.preferredDisplayMode = .allVisible
splitViewController.delegate = self//<<<<<<<<add this
}
override func awakeFromNib() {
super.awakeFromNib()
splitViewController?.delegate = self
splitViewController?.preferredDisplayMode = .allVisible
}
//MARK: Split View Controller Delegate
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController: UIViewController, onto primaryViewController: UIViewController) -> Bool {
print("splitview collapse method")
return false
}
Method is called at launch in Xcode 12.4 on Simulator iPhone, if you set: Storyboard -> Split View Controller -> Style -> Unspecified (Discouraged) not Double Column

UINavigationController inside UITabBarController inside UISplitViewController (still) shows detail controller modally instead of pushing

I have what seems to be a very common setup in my universal application, with a root UISplitViewController, using a UITabBarController as a masterViewController, and then I want to:
either push the detail view controller onto the stack if I'm on a vertical iPhone
show the detail controller in the detailViewController of the UISplitViewController on lanscape iPhone 6+ and other larger screens like iPads and such
To that effect, I have exactly the same setup as the ones described in all those discussions that mention a similar issue:
UINavigationController inside a UITabBarController inside a UISplitViewController presented modally on iPhone
iOS8 TabbarController inside a UISplitviewController Master
Adaptive show detail segue transformed to modal instead of push on iPhone when master view controller is a UITabBarController
But none of the solutions mentioned in those questions works. Some of them create an infinite recursive loop and an EXC_BAD_ACCESS. And the latest one I tried simply keeps presenting the detail view controller modally instead of pushing it onto the stack on iPhones. What I did is create a custom UISplitViewController subclass as such:
class RootSplitViewController: UISplitViewController {
override func viewDidLoad() {
super.viewDidLoad()
self.delegate = self
}
}
extension RootSplitViewController: UISplitViewControllerDelegate {
func splitViewController(_ splitViewController: UISplitViewController, showDetail vc: UIViewController, sender: Any?) -> Bool {
if let tabController = splitViewController.viewControllers[0] as? UITabBarController {
if(splitViewController.traitCollection.horizontalSizeClass == .compact) {
tabController.selectedViewController?.show(vc, sender: sender)
} else {
splitViewController.viewControllers = [tabController, vc]
}
}
return true
}
func splitViewController(_ splitViewController: UISplitViewController, separateSecondaryFrom primaryViewController: UIViewController) -> UIViewController? {
if let tabController = splitViewController.viewControllers[0] as? UITabBarController {
if let navController = tabController.selectedViewController as? UINavigationController {
return navController.popViewController(animated: false)
} else {
return nil
}
} else {
return nil
}
}
}
And here is the code in the master view controller to show the detail view controller:
self.performSegue(withIdentifier: "showReference", sender: ["tags": tags, "reference": reference])
Where tags and reference where loaded from Firebase. And of course the "showReference" segue is of the "Show Detail (e.g. Replace)" kind.
The first delegate method is called correctly, as evidenced by the breakpoint that gets hit there when I click an item in the list inside the UITabBarController. And yet the detail view controller still presents modally on iPhone. No problem on iPad though: the detail view controller appears on the right, as expected.
Most of the answers mentioned above are pretty old and some of the solutions are implemented in Objective-C so maybe I did something wrong in the conversion, or something changed in the UISplitViewController implementation since then.
Does anyone have any suggestion?
I figured it out. In fact, it was related to the target view controller I was trying to show. Of the 2 methods I was overriding in UISplitViewControllerDelegate, only the first one was called:
func splitViewController(_ splitViewController: UISplitViewController, showDetail vc: UIViewController, sender: Any?) -> Bool {
if let tabController = splitViewController.viewControllers[0] as? UITabBarController {
if(splitViewController.traitCollection.horizontalSizeClass == .compact) {
tabController.selectedViewController?.show(vc, sender: sender)
} else {
splitViewController.viewControllers = [tabController, vc]
}
}
return true
}
But the view controller I was showing in the first branch of the test was already embedded into a UINavigationController, so I was essentially showing a UINavigationController into another one, and in that case the modal made more sense. So in that case I needed to show the top view controller of the UINavigationController, which I assume was the purpose of the second method I'm overriding in the delegate, but it was never called. So I did it right there with the following implementation:
extension RootSplitViewController: UISplitViewControllerDelegate {
func splitViewController(_ splitViewController: UISplitViewController, showDetail vc: UIViewController, sender: Any?) -> Bool {
if let tabController = splitViewController.viewControllers[0] as? UITabBarController {
if(splitViewController.traitCollection.horizontalSizeClass == .compact) {
if let navController = vc as? UINavigationController, let actualVc = navController.topViewController {
tabController.selectedViewController?.show(actualVc, sender: sender)
navController.popViewController(animated: false)
} else {
tabController.selectedViewController?.show(vc, sender: sender)
}
} else {
splitViewController.viewControllers = [tabController, vc]
}
}
return true
}
}
And that seems to work perfectly, both on iPhones and iPads
Having you tried ShowDetailViewController Method to change the detail view controller in split view controller.
splitViewController.showDetailViewController(vc, sender: self)
If in case your view controller does not contain navigation controller you can also embed it in a navigation controller.
let nav = UINavigationController.init(rootViewController: vc)
splitViewController.showDetailViewController(nav, sender: self)

UISplitViewController show detail view on iPhone devices not master

I have implemented a UISplitViewController and all works fine. What I want to do is on iPhone devices only show the detailView not the masterView as the first view controller. I realise I can create a segue from the master view to the detail view in the masters viewDidLoad method however this feels a bit hacky to me. Maybe this is the only way to achieve what I want?
I have looked at the documentation for the UISplitViewControllerDelegate particularly this function however I don't feel I grasped what this actually is doing. I have also set the UISplitViewController as the delegate and set allVisible and tried all the other options in the viewDidLoad of my SplitViewController sub class
self.delegate = self
self.preferredDisplayMode = .allVisible
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController: UIViewController, onto primaryViewController: UIViewController) -> Bool {
return true
}
If it helps the detailViewController heirachy in the storyboard is SplitViewController > UINavigationController > myDetailViewController
What you need to do is to use the splitviewcontroller delegate function
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool
In there you can push your second controller into your first navigation controller and return true. Returning true means that you're gonna handle the transition. e.g.
func splitViewController(_ splitViewController: UISplitViewController, collapseSecondary secondaryViewController:UIViewController, onto primaryViewController:UIViewController) -> Bool {
if let detailViewController = secondaryViewController as? YourSecondViewController, let primaryNV = primaryViewController as? UINavigationController {
primaryNV.pushViewController(detailViewController, animated: false)
returns true // I handle it myself.
}
return false // let the iOS handles it.
}
If you need more clarification, please let me know. I'll try to explain it better. cheers!.

Adaptive show detail segue transformed to modal instead of push on iPhone when master view controller is a UITabBarController

In XCode 6, if you create a new project based on the Master-Detail Application template, you get a universal storyboard that is supposed to be good for all devices.
When selecting a cell in the master view, the detail view is updated via an adaptive "show detail" segue. On an iPhone 4, 5, 6 or 6+ in portrait, this segue will take the form of a push as expected. On an iPad or an iPhone 6+ in landscape, it will cause the detail view to be updated as expected.
Now, if you insert a UITabBarController as the master view controller which has a tab to the original master view controller, the adaptive segue that occurs when selecting a cell in the master view does not behave as expected on iPhones. Instead of getting a push transition, you now get a modal transition. How can I fix that? Seems odd that this is not supported by default.
I found the following post useful: iOS8 TabbarController inside a UISplitviewController Master
But when using the suggested method, I don't get the right behaviour on an iPhone 6 Plus when I rotate to landscape after a push in portrait. The content of the detail view appears in the master view which is not surprising since that's what the suggested solution does.
Thanks!
Re-watching videos from WWDC14 I think I've found a better answer.
Use a custom UISplitViewController (subclass)
Override the showDetailViewController operation
Use the traitCollection to determine the class of the UISplitViewController
If the horizontal class is Compact, get the navigationController to call showViewController
Here is the the code of the custom UISplitViewController :
import UIKit
class CustomSplitViewController: UISplitViewController {
override func showDetailViewController(vc: UIViewController!, sender: AnyObject!) {
if (self.traitCollection.horizontalSizeClass == UIUserInterfaceSizeClass.Compact) {
if let tabBarController = self.viewControllers[0] as? UITabBarController {
if let navigationController = tabBarController.selectedViewController as? UINavigationController {
navigationController.showViewController(vc, sender: sender)
return
}
}
}
super.showDetailViewController(vc, sender: sender)
}
}
Do not forget to the set the custom class in the storyboard.
Tested in the simulator of iPhone 6, iPhone 6+ and iPad Air and worked as expected.
Unfortunately, the selected answer didn't work for me. However, I did eventually manage to solve the problem:
Subclass UISplitViewController and set the new class in Interface Builder.
Make the new class conform to UISplitViewControllerDelegate:
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
self.delegate = self
}
Implement these two methods:
func splitViewController(_ splitViewController: UISplitViewController,
collapseSecondary secondaryViewController:UIViewController,
onto primaryViewController:UIViewController) -> Bool {
return true
}
func splitViewController(_ splitViewController: UISplitViewController,
showDetail vc: UIViewController,
sender: Any?) -> Bool {
if splitViewController.isCollapsed {
guard let tabBarController = splitViewController.viewControllers.first as? UITabBarController else { return false }
guard let selectedNavigationViewController = tabBarController.selectedViewController as? UINavigationController else { return false }
// Push view controller
var detailViewController = vc
if let navController = vc as? UINavigationController, let topViewController = navController.topViewController {
detailViewController = topViewController
}
selectedNavigationViewController.pushViewController(detailViewController, animated: true)
return true
}
return false
}
The docs state when the split controller is collapsed, it handles showDetail by calling show on the master view controller, which in your case is a tab controller. You need to forward that on to the child nav controller as follows:
Make a tab controller subclass.
In the storyboard set the tab controller to use the new subclass.
Add this method to the subclass:
- (void)showViewController:(UIViewController *)vc sender:(id)sender{
[self.viewControllers.firstObject showViewController:vc sender:sender];
}
This forwards it on to the nav controller in the first tab.

Resources