[iOS] TabView does not switch tabs / snaps back even though index updates

[hcrnln]

Environment

• react-native: 0.77
• react-native-tab-view: 4.0.5
• react-native-pager-view: 7.0.2 (also tried 6.9.1)
• Platform: iOS
• New Architecture: Enabled

Description

On iOS, tabs do not switch correctly when using react-native-tab-view with react-native-pager-view.

onIndexChange is triggered and the state index updates correctly, but the UI does not stay on the selected tab.

Observed behavior:

• pressing a tab does not visibly switch to that tab
• swiping sometimes looks like it changes page briefly, then snaps back to the first tab
• Android works as expected with the same code

Expected behavior

When a tab is pressed or swiped to, the selected tab should stay active and the scene should update correctly.

Actual behavior

On iOS:

• tab press triggers onIndexChange
• state updates
• but the visible page does not remain on the selected tab
• sometimes it briefly changes and returns back to the first tab

Notes

• Android works correctly
• issue reproduced on iOS
• New Architecture is enabled
• upgrading/downgrading app-side code paths did not resolve it
• side effects inside onIndexChange were removed for testing, but the issue still persisted

Additional notes

• I also tested the latest react-native-pager-view version.
• On iOS, that version threw: Unimplemented component <RNCViewPager>.
• Because of that, I downgraded back to 7.0.2 for testing.
• The tab switching issue still persists on 7.0.2.

Question

Is this a known iOS/New Architecture regression with react-native-pager-view 7.0.2?

[MrRefactor]

please try with 8.0.0

[hcrnln]

@MrRefactor Thank you for your feedback. I had previously tried version 8.0.0, but I'm getting the following error for iOS:

I also tried it with version 7.x here: #1065 and got the same error. I didn't get the "Unimplemented component: " error in version 6.9.1, but tab transitions don't work in that version either.