Wie zeige ich den Fortschrittsbalken unten an, wenn der Benutzer auf Elemente zugreift, die in einer Liste angezeigt werden?

Ich habe einen Code geschrieben, in dem ich Daten über den Webdienst erhalte. Jetzt möchte ich Teilaufzeichnungen auffüllen, da ich ungefähr @ hab 630 Datensätze in meinem JSON.

Hier ist mein gesamter Code, den ich verwende, um Daten aus JSON abzurufen und in RecyclerView einzufügen.

Hier sieht mein JSON aus, aber echtes JSON enthält über 600 Datensätze:

 http://walldroidhd.com/api.php

Kann mich jemand anleiten, wo ich Änderungen an meinem Code vornehmen muss?

Ich möchte mehr Datensätze auffüllen, wenn Benutzer mithilfe der Fortschrittsleiste nach unten scrollen. Trotzdem zeige ich alle Datensätze an.

RecyclerViewFragment.java:

public class RecyclerViewFragment extends Fragment {

    RecyclerView mRecyclerView;
    LinearLayoutManager mLayoutManager;
    RecyclerView.Adapter mAdapter;
    ArrayList<NatureItem> actorsList;

    private int previousTotal = 0;
    private boolean loading = true;
    private int visibleThreshold = 5;
    int firstVisibleItem, visibleItemCount, totalItemCount;

    public static RecyclerViewFragment newInstance() {
        return new RecyclerViewFragment();
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_recyclerview_advance, container, false);
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        actorsList = new ArrayList<NatureItem>();

        new JSONAsyncTask().execute("my JSON url");

        mRecyclerView = (RecyclerView) view.findViewById(R.id.recycler_view);
        mRecyclerView.setHasFixedSize(true);

        mLayoutManager = new GridLayoutManager(getActivity(), 2);
        mRecyclerView.setLayoutManager(mLayoutManager);

        mRecyclerView.setOnScrollListener(new RecyclerView.OnScrollListener() {

            @Override
            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
                super.onScrolled(recyclerView, dx, dy);

                visibleItemCount = mRecyclerView.getChildCount();
                totalItemCount = mLayoutManager.getItemCount();
                firstVisibleItem = mLayoutManager.findFirstVisibleItemPosition();

                if (loading) {
                    if (totalItemCount > previousTotal) {
                        loading = false;
                        previousTotal = totalItemCount;
                    }
                }
                if (!loading && (totalItemCount - visibleItemCount)
                        <= (firstVisibleItem + visibleThreshold)) {
                    // End has been reached

                    Log.i("...", "end called");

                    // Do something

                    loading = true;
                }
            }
        });

        // mAdapter = new CardAdapter();
        mAdapter = new RecyclerViewMaterialAdapter(new CardAdapter(getActivity(), actorsList), 2);
        mRecyclerView.setAdapter(mAdapter);

        MaterialViewPagerHelper.registerRecyclerView(getActivity(), mRecyclerView, null);

        mRecyclerView.addOnItemTouchListener(
                new RecyclerItemClickListener(getActivity(), new RecyclerItemClickListener.OnItemClickListener() {
                    @Override
                    public void onItemClick(View view, int position) {

                        Toast.makeText(getActivity(), String.valueOf(position), Toast.LENGTH_LONG).show();

                    }
                })
        );

    }

    class JSONAsyncTask extends AsyncTask<String, Void, Boolean> {

        ProgressDialog dialog;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            dialog = new ProgressDialog(getActivity());
            dialog.setMessage("Loading, please wait");
            dialog.setTitle("Connecting server");
            dialog.show();
            dialog.setCancelable(false);
        }

        @Override
        protected Boolean doInBackground(String... urls) {
            try {

                //------------------>>
                HttpGet httppost = new HttpGet(urls[0]);
                HttpClient httpclient = new DefaultHttpClient();
                HttpResponse response = httpclient.execute(httppost);

                // StatusLine stat = response.getStatusLine();
                int status = response.getStatusLine().getStatusCode();

                if (status == 200) {
                    HttpEntity entity = response.getEntity();
                    String data = null;
                    try {
                        data = EntityUtils.toString(entity);
                    } catch (IOException e) {
                        e.printStackTrace();
                    }


                    JSONObject jsono = null;
                    try {
                        jsono = new JSONObject(data);
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                    JSONArray jarray = jsono.getJSONArray("wallpapers");


                    for (int i = 0; i < jarray.length(); i++) {
                        JSONObject object = jarray.getJSONObject(i);

                        NatureItem actor = new NatureItem();

                        actor.setName(object.getString("id"));
                        actor.setThumbnail(object.getString("thumb_url"));

                        actorsList.add(actor);
                    }
                    return true;
                }

                //------------------>>

            } catch (ParseException e1) {
                e1.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } catch (JSONException e) {
                e.printStackTrace();
            }
            return false;
        }

        protected void onPostExecute(Boolean result) {
            dialog.cancel();
            mAdapter.notifyDataSetChanged();
            if (result == false) {
                Toast.makeText(getActivity(), "Unable to fetch data from server", Toast.LENGTH_LONG).show();
            }
            else {

            }

        }
    }
}

CardAdapter.java:

public class CardAdapter extends RecyclerView.Adapter<CardAdapter.ViewHolder> {

    private ArrayList<NatureItem> mItems;
    private Context mContext;

    public CardAdapter(Context context, ArrayList<NatureItem> feedItemList) {
        this.mItems = feedItemList;
        this.mContext = context;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
        View v = LayoutInflater.from(viewGroup.getContext())
                .inflate(R.layout.recycler_view_card_item, viewGroup, false);

        ViewHolder viewHolder = new ViewHolder(v);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(ViewHolder viewHolder, int i) {
        NatureItem nature = mItems.get(i);
        viewHolder.tvNature.setText(nature.getName());

        Picasso.with(mContext).load(nature.getThumbnail())
                .error(R.mipmap.ic_launcher)
                .placeholder(R.mipmap.ic_launcher)
                .into(viewHolder.imgThumbnail);

    }

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

    class ViewHolder extends RecyclerView.ViewHolder{

        public ImageView imgThumbnail;
        public TextView tvNature;

        public ViewHolder(View itemView) {
            super(itemView);
            imgThumbnail = (ImageView)itemView.findViewById(R.id.img_thumbnail);
            tvNature = (TextView)itemView.findViewById(R.id.tv_nature);
        }
    }
}

Hier ist, wie ich Endless auch implementiert habe, mitDie:,

mRecyclerView.setOnScrollListener(new EndlessRecyclerOnScrollListener(linearLayoutManager) {
            @Override
            public void onLoadMore(int current_page) {
                // do something...
            }
        });

Hinweis Ich persönlich würde die RecyclerView onScroll-Funktionalität vorziehen, um meine Arbeit zu erledigen.