JSON Android ListView

I build this webservice on netbeans, package in.figures.on.mobile; import db.koneksi.dbKoneksi; import java.sql.Statement; import java.sql.ResultSet; import java.util.ArrayList; i

Solution 1:

Ok. Try this bellow code. It is full functional to me. You should implement the HttpRequest in the commented line. Pay atention to that the JSON array is hard-coded.

// the Adapter
public class ListViewAdapter extends BaseAdapter {

    private Context context = null;
    private List<String> fields = null;

    public ListViewAdapter(Context context, JSONArray arr) {
        this.context = context;
        this.fields = new ArrayList<String>();
        for (int i=0; i<arr.length(); ++i) {
            try {
                fields.add(arr.getJSONObject(i).toString());
            } catch (JSONException e) {
                e.printStackTrace();
            }
        }
    }

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

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

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

    @Override
    public View getView(int position, View convertView, ViewGroup viewGroup) {
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(R.layout.itemlist, null);
        TextView txt = (TextView) convertView.findViewById(R.id.ItemList_txt);
        txt.setText(fields.get(position));
        return convertView;
    }

}

// the activity
public class ListViewActivity extends Activity {

    public final String result = "[{\"idPrimary_key\":\"21ye21\",\"kategori\":\"FirstCategory\"},{\"idPrimary_key\":\"89oy89\",\"kategori\":\"SecondCategory\"},{\"idPrimary_key\":\"34ew34\",\"kategori\":\"ThirdCategory\"}]";
    public final String obj = "{\"kat\":"+result+"}";

    private ListViewAdapter adapter = null;
    private ListView myList = null;
    private JSONArray items = new JSONArray();

    final Handler handler = new Handler() {
        @Override
        public void handleMessage(android.os.Message msg) {
            if (msg.what == 0) { // server returned null, try again
                loadFields();
            } else if(msg.what == 1) { // error in json
                // do something to treat it
            } else if (msg.what == 2) { // ready to roll the list
                adapter = new ListViewAdapter(ListViewActivity.this, items);
                myList.setAdapter(adapter);
                adapter.notifyDataSetChanged();
            }
        }
    };

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    myList = (ListView) findViewById(R.id.Lists_notificationsListview);
    loadFields();
}

private void loadFields() {
    new Thread() {
        @Override
        public void run() {
            Looper.prepare();
            StringBuilder builder = new StringBuilder(obj);
            if (builder != null) {
                try {
                    // HERE, you should implement the HTTP request...
                    items = new JSONObject(obj).getJSONArray("kat");
                    handler.sendEmptyMessage(2);
                } catch (JSONException e) {
                    handler.sendEmptyMessage(1);
                }
            } else {
                handler.sendEmptyMessage(0);
            }
            Looper.loop();
        }
    }.start();
}

And the xml files:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent" android:layout_height="fill_parent">
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent" android:layout_height="wrap_content"
        android:orientation="vertical"
        android:isScrollContainer="true">
        <ListView
            android:id="@+id/Lists_notificationsListview"
            android:layout_width="fill_parent" android:layout_height="match_parent">
        </ListView>
    </RelativeLayout>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent" android:layout_height="fill_parent">
    <TextView
        android:id="@+id/ItemList_txt"
        android:layout_width="fill_parent" android:layout_height="wrap_content"/>
</LinearLayout>

As result, it generates the following view:

Of course, you can customize it to create lists that you want, just parsing the jsons! Hope that I've helped in some way...