Creating an infinite ListView?

1

I'm trying to create an infinite ListView to go looking for information in my webservice every 10 minutes.

For this I'm trying to use this example: link

But I do not know how I can return from this example the offset and the limit to go sending to the webservice and it returns the amount of records I need.

EndlessScrollListener

public abstract class EndlessScrollListener implements AbsListView.OnScrollListener {
    // The minimum amount of items to have below your current scroll position
    // before loading more.
    private int visibleThreshold = 5;
    // The current offset index of data you have loaded
    private int currentPage = 0;
    // The total number of items in the dataset after the last load
    private int previousTotalItemCount = 0;
    // True if we are still waiting for the last set of data to load.
    private boolean loading = true;
    // Sets the starting page index
    private int startingPageIndex = 0;

    public EndlessScrollListener() {
    }

    public EndlessScrollListener(int visibleThreshold) {
        this.visibleThreshold = visibleThreshold;
    }

    public EndlessScrollListener(int visibleThreshold, int startPage) {
        this.visibleThreshold = visibleThreshold;
        this.startingPageIndex = startPage;
        this.currentPage = startPage;
    }

    // This happens many times a second during a scroll, so be wary of the code you place here.
    // We are given a few useful parameters to help us work out if we need to load some more data,
    // but first we check if we are waiting for the previous load to finish.
    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount)
    {
        // If the total item count is zero and the previous isn't, assume the
        // list is invalidated and should be reset back to initial state
        if (totalItemCount < previousTotalItemCount) {
            this.currentPage = this.startingPageIndex;
            this.previousTotalItemCount = totalItemCount;
            if (totalItemCount == 0) { this.loading = true; }
        }
        // If it’s still loading, we check to see if the dataset count has
        // changed, if so we conclude it has finished loading and update the current page
        // number and total item count.
        if (loading && (totalItemCount > previousTotalItemCount)) {
            loading = false;
            previousTotalItemCount = totalItemCount;
            currentPage++;
        }

        // If it isn’t currently loading, we check to see if we have breached
        // the visibleThreshold and need to reload more data.
        // If we do need to reload some more data, we execute onLoadMore to fetch the data.
        if (!loading && (totalItemCount - visibleItemCount)<=(firstVisibleItem + visibleThreshold)) {
            onLoadMore(currentPage + 1, totalItemCount);
            loading = true;
        }
    }

    // Defines the process for actually loading more data based on page
    public abstract void onLoadMore(int page, int totalItemsCount);

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        // Don't take any action on changed
    }
}

Fragment

public class NoticiaFrag extends Fragment {
    private ListView lvNoticias;
    private List<Noticia> listaNoticias = new ArrayList<Noticia>();
    private NoticiaListAdapter noticiaLA;
    private static final String TAG = "NoticiaFrag";
    protected ProgressDialog progressDialog;

    private static Integer OFFSET = 0, LIMIT = 10;

    //singleton
    private static NoticiaFrag mFrag;

    public static NoticiaFrag newInstance() {
        if(mFrag == null){
            mFrag = new NoticiaFrag();
        }
        return mFrag;
    }

    public NoticiaFrag() {
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view =  inflater.inflate(R.layout.noticia_frag, container, false);

        lvNoticias = (ListView)view.findViewById(R.id.lvNoticias);
        lvNoticias.setOnScrollListener(new EndlessScrollListener() {
            @Override
            public void onLoadMore(int page, int totalItemsCount) {
                customLoadMoreDataFromApi(page);
            }
        });

        return view;
    }



    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        customLoadMoreDataFromApi(OFFSET);

    }


    // Append more data into the adapter
    public void customLoadMoreDataFromApi(int offset) {
        OFFSET = (offset - 1) * LIMIT;
        LIMIT = (2 * OFFSET);
        Log.i("OFFSET", OFFSET + "");
        Log.i("LIMIT", LIMIT + "");

        progressDialog = new CustomProgressDialog().getCustomProgress(null, getView().getContext());
        progressDialog.show();
        try {
            JsonObjectRequest app = new NoticiaDAO().getAllNoticias(LIMIT, OFFSET, new NoticiasAdapter() {
                @Override
                public void getAllNoticias(List<Noticia> lista) {
                    Log.w("SIZELIST->", lista.size()+ "") ;
                    if(!lista.isEmpty()){
                        listaNoticias = lista;
                        noticiaLA.changeLista(listaNoticias);
                    }else{
                        Toast.makeText(getView().getContext(), "Nenhuma noticia encontrada", Toast.LENGTH_SHORT).show();
                    }
                    progressDialog.dismiss();
                }
            });
            CustomVolleySingleton.getInstance().addToRequestQueue(app);
        }catch (Exception e ){
            Log.e("ERROR: " + TAG, "Method: " + "getAllNoticias: " + e);
        }

    }


    @Override
    public void onResume() {
        super.onResume();
        ChangeActionBar.changeActionBar(getActivity(), "Notícias", false, "");
    }


    @Override
    public void onPause() {
        super.onPause();
        CustomVolleySingleton.getInstance().cancelPendingRequests(CustomVolleySingleton.TAG);
        ChangeActionBar.changeActionBar(getActivity(), null, false, "");
    }



}

NewsListAdapter

public class NoticiaListAdapter extends BaseAdapter {
    private Context context;
    private List<Noticia> lista;


    public NoticiaListAdapter(Context context, List<Noticia> lista) {
        this.context = context;
        this.lista = lista;
    }


    public void changeLista(List<Noticia> lista){
        for(Noticia n : lista){
            this.lista.add(n);
        }
        notifyDataSetChanged();
    }

    @Override
    public int getCount() {
        return lista.size();
    }

    @Override
    public Object getItem(int position) {
        return lista.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        final ViewHolder holder;
        Noticia noticia = lista.get(position);
        if (convertView == null) {
            holder = new ViewHolder();
            LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.noticia_listadapter, parent, false);

            holder.llNoticiaListAdapter = (LinearLayout) convertView.findViewById(R.id.llNoticiaListAdapter);
            holder.sivNoticia = (SmartImageView)convertView.findViewById(R.id.sivNoticia);
            holder.tvTitulo = (TextView) convertView.findViewById(R.id.tvTitulo);
            holder.wvDescricao = (WebView) convertView.findViewById(R.id.wvDescricao);
            holder.tvData = (TextView) convertView.findViewById(R.id.tvData);
            holder.tvAutor = (TextView) convertView.findViewById(R.id.tvAutor);

            convertView.setTag(holder);
        }else{
            holder = (ViewHolder)convertView.getTag();
        }


        if(noticia.getImage() == null){
            holder.sivNoticia.setImageDrawable(context.getResources().getDrawable(R.drawable.no_image_news));
        }else{
            holder.sivNoticia.setImageUrl(WebServiceURL.getBaseWebServiceURL() + "app/webroot/img/noticias/" + noticia.getImage());
        }

        holder.tvTitulo.setText(noticia.getTitulo());
        holder.wvDescricao.loadData(formatDescricao(noticia.getDescricao()), "text/html; charset=utf-8", null);
        holder.tvData.setText(new DateControl().getDataHoraFormat(noticia.getCreated()));
        holder.tvAutor.setText("Por: " + noticia.getUsuario());

        return convertView;
    }

    private String formatDescricao(String descricao){
        StringBuilder html = new StringBuilder();
        html.append("<html>");
        html.append("<body>");
        html.append("<small>");
        html.append("<p align=\"justify\" style=\"color:gray\">");
        html.append(descricao);
        html.append("</p");
        html.append("</small>");
        html.append("</body>");
        html.append("</html>");

        return html.toString();

    }

    private static class ViewHolder{
        LinearLayout llNoticiaListAdapter;
        SmartImageView sivNoticia;
        TextView tvTitulo;
        WebView wvDescricao;
        TextView tvData;
        TextView tvAutor;

    }
}
    
asked by anonymous 15.09.2015 / 15:49

0 answers