[TabLayout] TabLayout Scroll Bug: Left Tab Misalignment After Fast Scroll

Description:

When performing a fast horizontal scroll that moves the entire TabLayout to the right, we expect the leftmost tab to return to an x = 0 position.

However, it appears that the leftmost tab occasionally snaps back to a negative x-position instead.

When this happens, tapping on any tab has no immediate effect. Instead, multiple taps are required before the leftmost tab returns to a non-negative x-position.

Until it returns to the correct position, all tab taps become unresponsive, except that they seem to gradually nudge the layout back toward alignment.

In the video, you can observe a small gap between the leftmost tab and the screen’s edge immediately after a fast scroll - this gap indicates the misalignment.

https://youtu.be/tl8PDvkRHYo

Expected behavior: Left most tab will never reach negative x position

Source code:

private void initTabs() {
    if (noteFragmentStateAdapter == null) {
        noteFragmentStateAdapter = new NoteFragmentStateAdapter(this, tabInfos);
        viewPager.setAdapter(noteFragmentStateAdapter);

        new TabLayoutMediator(tabLayout, viewPager,
                (tab, position) -> tab.setText(noteFragmentStateAdapter.getPageTitle(position))
        ).attach();

        viewPager.unregisterOnPageChangeCallback(onPageChangeListener);
        viewPager.registerOnPageChangeCallback(onPageChangeListener);

        // http://stackoverflow.com/questions/9857420/viewpager-fragments-getting-destroyed-over-time
        viewPager.setOffscreenPageLimit(1);
    } else {
        noteFragmentStateAdapter.notifyDataSetChanged();
    }

    int selectedNoteTabIndex = WeNoteOptions.getSelectedNoteTabIndex();

    setSelectedNoteTab(selectedNoteTabIndex);
}

Minimal sample app repro: (Sorry. I will provide a sample in next few days)

Android API version: Android API 35

Material Library version: Material Android Library version you are using here (e.g., 1.1.0-alpha07)

Device: Emulator Pixel 8 Pro API 35 arm64-v8a

https://github.com/user-attachments/assets/dfc811b2-35a6-4a52-925b-78d1d94390fa

To help us triage faster, please check to make sure you are using the latest version of the library.

We also happily accept pull requests.

Parti dal punto di ingresso initTabs() mostrato nel report e riproduci lo scorrimento orizzontale rapido sull’emulatore Pixel 8 Pro API 35 con Material 1.12.0. Verifica che la scheda più a sinistra non raggiunga una posizione x negativa e che i tocchi sulle schede rispondano immediatamente dopo lo scorrimento.