RecyclerView在螢屏旋轉時重新創建

`

class MoviesFragment : Fragment() {

    private var viewModel: MoviesViewModel? = null
    private var adapter = MoviesAdapter()
    private lateinit var binding : FragmentMoviesBinding

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View {
        binding = FragmentMoviesBinding.inflate(inflater, container, false)
        return binding.root
    }

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

    private fun recyclerViewInit() {
        val recyclerView = binding.recyclerView
        recyclerView.adapter = adapter
        recycler_view.layoutManager = LinearLayoutManager(requireContext())
    }

    private fun viewModelInit() {
        viewModel = ViewModelProvider(this)[MoviesViewModel::class.java]
        viewModel!!.getPageOfMovies()
        viewModel!!.myResponse.observe(viewLifecycleOwner) { response ->
            if (response.isSuccessful) {
                response.body()?.let { movies ->
                    adapter.setData(movies) }
            } else {
                Toast.makeText(requireContext(), response.code(), Toast.LENGTH_SHORT).show()
            }

        }
    }
}

`

`

class MoviesViewModel(application: Application) : AndroidViewModel(application) {

    private val repository = MoviesRepository()
    val myResponse: MutableLiveData<Response<MovieResponse>> = MutableLiveData()

    fun getPageOfMovies() {
        viewModelScope.launch {
            val response = repository.getPageOfMovies()
            myResponse.value = response
        }
    }
}

`

`

class MoviesAdapter : RecyclerView.Adapter<MoviesAdapter.ViewHolder>() {
    private var moviesList = MovieResponse(0, emptyList(), 0, 0)

    inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView)

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        return ViewHolder(
            LayoutInflater.from(parent.context).inflate(
                R.layout.movies_recyclerview_item, parent, false
            )
        )
    }

    override fun getItemCount(): Int = moviesList.results.size

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        Glide.with(holder.itemView.context)
            .load(Uri.parse("$BASE_URI_FOR_IMAGES${moviesList.results[position].posterPath}"))
            .centerCrop()
            .into(holder.itemView.poster_imageview)
        holder.itemView.title.text = moviesList.results[position].title
        holder.itemView.overview.text = moviesList.results[position].overview
        holder.itemView.release_date.text = moviesList.results[position].releaseDate
    }

    @SuppressLint("NotifyDataSetChanged")
    fun setData(movies: MovieResponse) {
        moviesList = movies
        notifyDataSetChanged()
    }

    companion object{
        const val BASE_URI_FOR_IMAGES = "https://www.themoviedb.org/t/p/w220_and_h330_face/"
    }
}

`

`

class MoviesRepository {
    suspend fun getPageOfMovies(): Response<MovieResponse> {
        return MoviesClient.api.getFirstPageOfPopularMovies()
    }
}

`

當螢屏在 RecyclerView 中旋轉時，資料再次加載到新的頂部，即串列在串列的頂部。可能是什么問題呢？也就是說，我可以滾動并查看我的資料，但在后臺我會看到我的舊串列。

我試圖找到我重新創建 RecyclerView 的位置，但顯然一切都應該作業。

uj5u.com熱心網友回復：

默認情況下，螢屏旋轉和其他配置更改會重新創建您的活動。重新創建的活動將恢復其片段。您應該只在活動重新開始且未重新創建時重新添加片段，即savedInstanceState捆綁包為空。否則，您將在已恢復的片段之上添加一個新片段。

標籤：爪哇安卓科特林android-recyclerview

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