WOOMOB-1009

Description

When the Woo app is initially launched and user logs in, Orders and Products tab are not displayed in a split view. The app needs to be killed and relaunched for a split view to appeared.

The iPadOS 18 + Xcode 16 hack was not working properly on first launch after login because it requires view.window to be available to access the window's trait collection. It turns all the views into .compact, not just the tab bar itself.

During initial login flow:

1. viewDidLoad() is called before tab controller is added to window hierarchy
2. AppCoordinator.displayLoggedInUI() sets tab controller as window root
3. view.window becomes available, but fixTabBarTraitCollectionOnIpadForiOS18 was already called when window was nil

Wrong solution

Calling fixTabBarTraitCollectionOnIpadForiOS18 on viewDidAppear was a bad choice (implemented in #15985 and reverted in #15988). The fix worked with the first login, but would make tabs appear correctly after a delay during the subsequent launch, also sometimes causing crashes when opening Order and Product tabs.

Better solution

There are two issues that need to be fixed with the original fixTabBarTraitCollectionOnIpadForiOS18 solution:

• window is not yet accessible to get an overall traitCollection collection if the viewController is not added in the view hierarchy
• tabs are not yet loaded

To solve those issues we can do two things:

• window is not yet accessible on a view but can be accessed through AppDelegate.shared.window, since the window it self is loaded.
• Call fixTabBarTraitCollectionOnIpadForiOS18 after tabs are loaded (fixTabBarTraitCollectionOnIpadForiOS18)

Steps to reproduce

First Launch

1. Remove the app
2. Install the app on the iPad
3. Login
4. Open Orders or Products tab
5. Confirm they appear in the split view

Subsequent Launches

1. Kill and relaunch the app
2. Open Orders or Products tab
3. Confirm they appear in the split view

Testing information

On iPad Air 18.5 simulator and iPad Air M2 26. device:

• Tested first and subsequent launches
• Tested logging out and logging in
• Tested self-hosted and Dotcom login paths
• Tested system split views, tested changing window sizes with iPadOS 26, tested changing orientations

• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.