问题描述
我有一个用 ArrayList 填充的 ListView,它工作正常,但是当我用新项目清除并重新填充 ArrayList 并调用 notifyDataSetChanged() 时,永远不会调用适配器的 getView(),而不会调用 ListView反映新数据。不知道我哪里出错了,但任何帮助表示赞赏!谢谢
初始化视图和适配器
Arraylist<Movie> moviesArray = new Arraylist<>();
movieListView = view.findViewById(R.id.movie_list_view);
movielistadapter = new MovieListArrayAdapter(this,requireContext(),R.layout.list_item,moviesArray);
movieListView.setAdapter(movielistadapter);
调用新数据
moviesArray.clear()
moviesviewmodel.GetMovies();
观察结果(我的BottomSheet得到更新,所以我知道我正在接收数据)
moviesviewmodel.getMoviesResult().observe(getViewLifecycleOwner(),new Observer<MovieList>() {
@Override
public void onChanged(MovieList movieList) {
if (movieList!=null) {
moviesArray.addAll(movieList.getResults());
movielistadapter.notifyDataSetChanged();
}
UpdateBottomSheet(view,0);
}
});
适配器(更新列表数据时不调用getView)
public class MovieListArrayAdapter extends ArrayAdapter<Movie> {
Fragment fragment;
List<Movie> movies;
public MovieListArrayAdapter(Fragment fragment,@NonNull Context context,int resource,@NonNull List<Movie> movies) {
super(context,resource,movies);
this.fragment = fragment;
this.movies = movies;
}
@NonNull
@Override
public View getView(int position,@Nullable View convertView,@NonNull ViewGroup parent) {
Movie movie = movies.get(position);
Movie top_movie = movies.get(0);
if (convertView == null) {
convertView = LayoutInflater.from(getContext()).inflate(R.layout.list_item,parent,false);
}
ImageView movie_imageview = convertView.findViewById(R.id.list_item_image);
if (movie==top_movie) {
convertView.setVisibility(View.VISIBLE);
Glide.with(fragment.requireContext()).load(movie.getimage()).into(movie_imageview);
} else {
convertView.setVisibility(View.GONE);
}
return convertView;
}
解决方法
您需要更新适配器中的列表。
movieListAdapter.addAll(movieList.getResults());
movieListAdapter.notifyDataSetChanged();