android - "restore scroll position in android Paging adapter when user go to another fragment or activity from adapter"问题

Question

当我移动到另一个 fragment 时，我如何恢复分页适配器项状态？我试过下面的文章，但没有用。 https://medium.com/@florina.muntenescu

private fun loadData() {
        viewModel.apply {
            lifecycleScope.launch{
                viewModel.getMorePopularMovies().collectLatest { pagingData ->
                    dataAdapter.submitData(viewLifecycleOwner.lifecycle, pagingData)

                }
            }
        }

    }

fun getMorePopularMovies() = Pager(
        PagingConfig(pageSize = 3)
) {
    VerticalMoviePagingSource(api, "Popular")
}.flow

Answer 1

尝试在您的 viewModel 代码中添加 .cachedIn(viewModelScope)。对于您的案例，您将获得:

  fun getMorePopularMovies() = Pager(
        PagingConfig(pageSize = 3)
) {
    VerticalMoviePagingSource(api, "Popular")
}.flow.cachedIn(viewModelScope)

并尝试在您的 fragment 中添加:

adapter.stateRestorationPolicy =
        RecyclerView.Adapter.StateRestorationPolicy.PREVENT_WHEN_EMPTY

如果它不起作用，那么我猜你的代码中还有另一个问题。