TabLayout不会滚动到选定的选项卡

如何解决TabLayout不会滚动到选定的选项卡

我在MainActivity的AppBarLayout中有一个TabLayout，在TransactionsFragment中有aViewPager2。 我在使用TabLayout时遇到问题，如下所示：

当我从上一个活动返回MainActivity时， viewPager2设置为正确的页面，但是TabLayout不会滚动到选定的选项卡。

我尝试过

viewPager2.currentItem = xxx or
tabLayout.selectTab(tabLayout.getTabAt(xxx))

在TransactionsFragment中，但我没有滚动到突出显示的选项卡。您能告诉我代码有什么问题吗？谢谢。

TransactionFragment.kt

class TransactionsFragment : Fragment() {
    
    lateinit var viewPagerAdapter: TabFragmentStateAdapter
    private lateinit var tabLayout: TabLayout
    private var pagerPos = -1

    override fun onViewCreated(view: View,savedInstanceState: Bundle?) {
        super.onViewCreated(view,savedInstanceState)
        setUpViewPager()
        setupObservers()
    }

    override fun onStop() {
        super.onStop()
        viewModel.tabLayoutPos = binding.mainViewPager.currentItem
    }

    private fun setupObservers() {
        viewModel.tabInfoList.observe(viewLifecycleOwner)
        {
            if (it != null) {
                viewPagerAdapter.tabInfoList = it

                //set the viewPager to the page user last seen
                pagerPos = it.size - 2
                if (viewModel.tabLayoutPos != -1)
                    pagerPos = viewModel.tabLayoutPos

                if (it.size > 2)
                    binding.mainViewPager.currentItem = pagerPos
                    //tabLayout.selectTab(tabLayout.getTabAt(pagerPos))
                else
                    binding.mainViewPager.currentItem = 0
                    //tabLayout.selectTab(tabLayout.getTabAt(0))
            }
        }

        viewModel.timeRange.observe(viewLifecycleOwner) {
            viewPagerAdapter.timeRange = it
        }
    }

    private fun setUpViewPager() {
        tabLayout = (requireActivity() as MainActivity).getTabLayout()
        viewPagerAdapter =
            TabFragmentStateAdapter(this)

        binding.apply {
            mainViewPager.adapter = viewPagerAdapter
            mainViewPager.offscreenPageLimit = 2

            TabLayoutMediator(tabLayout,binding.mainViewPager,true) { tab,position ->
                tab.text = viewPagerAdapter.tabInfoList[position].tabTitle
            }.attach()

            //fix the weird error of viewpager2,where switch to another time range and back to month
            //caused it to shrink,no idea why lol
            mainViewPager.updateLayoutParams {
                this.height = ViewGroup.LayoutParams.MATCH_PARENT
            }

            tabLayout.tabMode = TabLayout.MODE_AUTO
        }
    }

}

TabFragmentStateAdapter.kt

class TabFragmentStateAdapter(fragment : Fragment) :
    FragmentStateAdapter(fragment) {

    var tabInfoList: List<TabInfo> = listOf()
        set(value) {
            field = value
            notifyDataSetChanged()
        }

   ......
}