android - 如何用 RecyclerView 实现无限滚动？

Question

我有一个回收器，里面有卡片 View ，我从 REST 服务中获取信息，我正在尝试实现无限滚动，假设用户每次向下滚动时都会看到 10 个卡片 View ，直到没有要显示更多的卡片 View ，我该如何实现？

我看过几个例子，但没有一个能真正帮助我了解如何去做。我什至不知道我需要在 adapter.class 或 Fragment.class 中放入什么，因为我不知道如何实现它，如果有人能告诉我实现无限滚动的正确方法，那就太好了我的代码...

提前致谢。

MainAdapter.class

public class MainAdapter extends RecyclerView.Adapter<MainAdapter.ViewHolder> implements View.OnClickListener
{
    private ArrayList<Business> businessList;
    private Activity activity;
    private int layoutMolde,idb;

    public MainAdapter(Activity activity, ArrayList<Business> list, int layout) 
    {
        this.activity = activity;
        this.businessList = list;
        layoutMolde = layout;
    }

    @Override
    public MainAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) 
    {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.main_row, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) 
    {
        holder.mTitle.setText(businessList.get(position).getBusiness_name());
        holder.number_rating.setText(businessList.get(position).getRating().toString());
        Glide.with(activity).load(businessList.get(position).getLogo_url_string()).into(holder.mImg);
    }

    @Override
    public int getItemCount() {
        return businessList.size();
    }

    @Override
    public void onClick(View v) 
    {

    }

    public class ViewHolder extends RecyclerView.ViewHolder {

        public TextView mTitle;
        public ImageView mImg;
        public ImageView logo;
        public RatingBar main_rating;
        public TextView number_rating;

        public ViewHolder( View itemView) 
        {
            super(itemView);
            mTitle = (TextView) itemView.findViewById(R.id.nom_business_main);
            number_rating = (TextView) itemView.findViewById(R.id.number_rating);
            mImg = (ImageView) itemView.findViewById(R.id.img_main);
            main_rating=(RatingBar) itemView.findViewById(R.id.rating_main);
            main_rating.setRating((float)1);
            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v)
                {

                    Intent in = new Intent(v.getContext(), BusinessPremium.class);
                    int position = getAdapterPosition();
                    idb = businessList.get(position).getId();
                    in.putExtra("no", idb);
                    v.getContext().startActivity(in);
                }
            });
        }
    }
}

FeedsFragment.class

    public class FeedsFragment extends Fragment
    {

        private ArrayList<Business> arrayBusiness,arrayBasics;
        private Gson gson;

        private static final Type BUSINESS_TYPE = new TypeToken<ArrayList<Business>>() {}.getType();
        private RecyclerView.LayoutManager mLayoutManager;

        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) 
        {
            View android = inflater.inflate(R.layout.fragment_feeds, container, false);

            if (!internetConnectionCheck(FeedsFragment.this.getActivity())) 
            {
                Toast.makeText(getApplicationContext(), "Error de Conexión", Toast.LENGTH_LONG).show();
            }

            new RequestBase(getActivity()) {

                @Override
                public JsonObject onHttpOk(JsonObject response) throws JSONException {

                    JsonObject objeto, pagination_details = null, details, premium_img;
                    JsonArray data;

                    if (getActivity() == null)
                        return response;

                    if (response.get("pagination") == null) 
                    {
                        objeto = response;

                    } else {
                        objeto = response;
                        pagination_details = response.get("pagination").getAsJsonObject();
                        data = objeto.get("data").getAsJsonArray();
                        gson = new Gson();
                        arrayBusiness = gson.fromJson(data, BUSINESS_TYPE);
                        Log.d("size", String.valueOf(arrayBusiness.size()));
                        FeedsFragment.this.getActivity().runOnUiThread(new Runnable()
                        {
                            @Override
                            public void run() 
                            {

                                RecyclerView recycler = (RecyclerView) FeedsFragment.this.getActivity().findViewById(R.id.recycler_main);
                                MainAdapter adapter = new MainAdapter(getActivity(), arrayBusiness, R.layout.main_row);

                                recycler.setNestedScrollingEnabled(false);
                                mLayoutManager = new GridLayoutManager(FeedsFragment.this.getActivity(), 2);
                                recycler.setLayoutManager(mLayoutManager);
                                recycler.setAdapter(adapter);

                                GifTextView loading = (GifTextView)FeedsFragment.this.getActivity().findViewById(R.id.loading);
                                TextView loadingText = (TextView)FeedsFragment.this.getActivity().findViewById(R.id.loadingText);
                                loading.setVisibility(View.GONE);
                                loadingText.setVisibility(View.GONE);

                            }
                        });
                    }
                    if (pagination_details.isJsonNull()) {
                        Log.d("Paginacion", pagination_details.toString());
                    }
                    return objeto;
                }

                @Override
                public void onHttpCreate(JsonObject response) throws JSONException 
                {

                }

                @Override
                public void onHttpUnprocessableEntity(JsonObject response) throws JSONException 
                {
                    this.cancel(true);
                    final String error = response.get("errors").toString();
                    getActivity().runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            Toast.makeText(getActivity().getApplicationContext(), error, Toast.LENGTH_LONG).show();
                        }
                    });
                }
            }.execute("businesses/premiums", "GET");

            return android;
        }
}

Answer 1

您可以在 android 中使用 SwipeRefreshLayout 刷新并在刷新覆盖方法中调用您的 api

注意:将您的 API 调用请求放在一个方法中，然后在您的 SwipeRefreshLayout 的 onRefresh 方法中调用该方法