Android，用Retrofit填充Endless List View数据的最佳方法？

Question

I've success to populate data into listview, but my way seems very bad because when i scroll the list view, the retrofit always get All the Repository. So, what is the best way to populate Endless List view's data with retrofit ? Thanks ...

MainActivity.java

    public class MainActivity extends Activity {

        public static final String ENDPOINT = "http://rfhan.com";
        private List<Tempat> tempatList;
        private TempatAdapter tadapter;
        private EndlessListView lv;
        private int start=0;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            tempatList = new ArrayList<Tempat>();
            tadapter = new TempatAdapter(this, R.layout.item_tempat, tempatList);
            lv = (EndlessListView) findViewById(R.id.el);
            lv.setLoadingView(R.layout.loading_layout);
            lv.setAdapter(tadapter);

            //init data to my list
            requestData();

            //scroll listener
            lv.setListener(new EndlessListener() {

                @Override
                public void loadData() {
                    requestData();
                }
            });
        }

        private void requestData(){

            RestAdapter adapter = new RestAdapter.Builder()
                .setEndpoint(ENDPOINT)
                .build();

            TempatAPI api = adapter.create(TempatAPI.class);
            api.getAllData(new Callback<List<Tempat>>() {


                //here the problem 
                @Override
                public void success(List<Tempat> data, Response arg1) {
                    updateData(data);
                }

                @Override
                public void failure(RetrofitError arg0) {

                    Toast.makeText(MainActivity.this, "Retrofit Error!", Toast.LENGTH_LONG).show();
                    Toast.makeText(MainActivity.this, arg0+"", Toast.LENGTH_LONG).show();   
                }
            });
        }

        //the tmpt list is contain all Tempat's data
        //code below is to get some tmpt's data into new Arraylist
        //and update the adapter's data
        //it's work but seems bad way

        private void updateData(List<Tempat> tmpt){
            tempatList = new ArrayList<Tempat>(); 
            start+=10;
            for(int i=start-10;(i<start&&start<tmpt.size());i++)
            tempatList.add(tmpt.get(i));
            lv.addNewData(tempatList);
        }

        protected boolean isOnline() {
            ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
            NetworkInfo netInfo = cm.getActiveNetworkInfo();
            if (netInfo != null && netInfo.isConnectedOrConnecting()) {
                return true;
            } else {
                return false;
            }
        }
   }

Model Tempat.java

import java.math.BigInteger;
import android.graphics.Bitmap;

public class Tempat {

    BigInteger idkoleksi;
    String nama;
    String kategori;
    String alamat;
    String notelp;
    String jambuka;
    String jamtutup;
    String harga;
    String imageHeaderURL;
    double latitude;
    double longitude;
    int jumlahview;
    int jumlatrate;
    double rating;
    String tanggal;
    Bitmap bitmap;

    public BigInteger getIdkoleksi() {
        return idkoleksi;
    }
    public String getNama() {
        return nama;
    }
    public String getKategori() {
        return kategori;
    }
    public String getAlamat() {
        return alamat;
    }
    public String getNotelp() {
        return notelp;
    }
    public String getJambuka() {
        return jambuka;
    }
    public String getJamtutup() {
        return jamtutup;
    }
    public String getHarga() {
        return harga;
    }
    public String getImageHeaderURL() {
        return imageHeaderURL;
    }
    public double getLatitude() {
        return latitude;
    }
    public double getLongitude() {
        return longitude;
    }
    public int getJumlahview() {
        return jumlahview;
    }
    public int getJumlatrate() {
        return jumlatrate;
    }
    public double getRating() {
        return rating;
    }
    public String getTanggal() {
        return tanggal;
    }
    public void setIdkoleksi(BigInteger idkoleksi) {
        this.idkoleksi = idkoleksi;
    }
    public void setNama(String nama) {
        this.nama = nama;
    }
    public void setKategori(String kategori) {
        this.kategori = kategori;
    }
    public void setAlamat(String alamat) {
        this.alamat = alamat;
    }
    public void setNotelp(String notelp) {
        this.notelp = notelp;
    }
    public void setJambuka(String jambuka) {
        this.jambuka = jambuka;
    }
    public void setJamtutup(String jamtutup) {
        this.jamtutup = jamtutup;
    }
    public void setHarga(String harga) {
        this.harga = harga;
    }
    public void setImageHeaderURL(String imageHeaderURL) {
        this.imageHeaderURL = imageHeaderURL;
    }
    public void setLatitude(double latitude) {
        this.latitude = latitude;
    }
    public void setLongitude(double longitude) {
        this.longitude = longitude;
    }
    public void setJumlahview(int jumlahview) {
        this.jumlahview = jumlahview;
    }
    public void setJumlatrate(int jumlatrate) {
        this.jumlatrate = jumlatrate;
    }
    public void setRating(double rating) {
        this.rating = rating;
    }
    public void setTanggal(String tanggal) {
        this.tanggal = tanggal;
    }
    public Bitmap getBitmap() {
        return bitmap;
    }
    public void setBitmap(Bitmap bitmap) {
        this.bitmap = bitmap;
    }





}

Repository TempatAPI.java

import java.util.List;

import retrofit.Callback;
import retrofit.http.GET;

public interface TempatAPI {
    @GET("api/tempat/get_all_data.php")
    public void getAllData(Callback<List<Tempat>> response);
}

Webservice API get_all_data.php

<?php

$response = array();
require_once __DIR__ . '/db_connect.php';

$db = new DB_CONNECT();
$nama=$_GET["nama"];

$query = "SELECT DataKoleksi.* , DataStatistikKoleksi.* FROM DataKoleksi, DataStatistikKoleksi WHERE DataKoleksi.idkoleksi = DataStatistikKoleksi.idkoleksi";
$result = mysql_query($query) or die(mysql_error());
$response = array();

if (mysql_num_rows($result) > 0) {



    while ($row = mysql_fetch_array($result)) {

        $koleksi = array();
        $koleksi["idkoleksi"] = $row["idkoleksi"];
        $koleksi["nama"] = $row["nama"];
        $koleksi["kategori"] = $row["kategori"];
        $koleksi["alamat"] = $row["alamat"];
        $koleksi["notelp"] = $row["notelp"];
        $koleksi["jambuka"] = $row["jambuka"];
        $koleksi["jamtutup"] = $row["jamtutup"];
        $koleksi["harga"] = $row["harga"];
        $koleksi["imageHeaderURL"] = $row["imageHeaderURL"];
        $koleksi["latitude"] = $row["latitude"];
        $koleksi["longitude"] = $row["longitude"];

        $koleksi["jumlahview"] = $row["jumlahview"];
        $koleksi["jumlahrate"] = $row["jumlahrate"];
        $koleksi["rating"] = $row["rating"];
        $koleksi["tanggal"] = $row["tanggal"];

        array_push($response, $koleksi);
    }
    echo json_encode($response);
} else {
    // no found
    echo json_encode($response);
}
?>

Answer 1

You need to add a listener to your listview to see if you have scrolled to the end of the list. In my example below, we check if we have reached the end of the list and if we have, we try to load 10 more items. The listview is then updated.

lvEvents.setOnScrollListener(new AbsListView.OnScrollListener() {
    @Override
    public void onScrollStateChanged(AbsListView absListView, int scrollState) {}

    @Override
    public void onScroll(AbsListView absListView, int firstVisible, int visibleCount, int totalCount) {
        boolean loadMore = firstVisible + visibleCount >= totalCount;

        if (loadMore && !isLoadingEvents && futureEvents.size() >= 10 && !noMoreEvents) {
            Log.d(TAG, "LOADING MORE EVENTS");
            isLoadingEvents = true;
            networkManager.getTenMoreEvents(getActivity(), new NetworkManager.Request() {
                @Override
                public void finished() {
                    updateEventsFeed();
                    isLoadingEvents = false;
                }
            });
        }
    }

});