Java 正在创建搜索应用程序，但listview为空

我正在为每个屏幕构建一个使用片段的搜索应用程序。我让搜索工作并将JSON结果存储在主活动中的ArrayListin中，以便其他片段可以访问它。当前的问题是我的resultsFragment，我在主ListFragment中嵌入了一个Google MapFragment，下面是一个listView。映射已成功填充，但列表为空。我花了好几个小时试图弄明白这一点。下面是resultsFragment的代码

package com.wny.wecare.fragment;

import java.util.ArrayList;
import java.util.Map;

import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.MapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.wny.wecare.MainActivity;
import com.wny.wecare.R;

import android.app.ListFragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;

public class ResultsFragment extends ListFragment {

    ArrayList<Map<String, String>> resultsList = new ArrayList<Map<String, String>>();

    private GoogleMap map;

    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.fragment_results, container, false);

        //Get search results from stored ArrayList
        resultsList = MainActivity.getResultsList();

        //Build listView from results
        ListView lv =(ListView) getActivity().findViewById(android.R.id.list);

        ListAdapter adapter = new SimpleAdapter(getActivity(), resultsList,
                R.layout.custom_row_view, new String[] { "AgencyID", "AgencyName",
        "Address1" }, new int[] { R.id.text1, R.id.text2,
            R.id.text3 });

        // updating listview
        setListAdapter(adapter);

        //Setup embedded Google Map fragment
        map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map))
                .getMap();
        map.setMapType(GoogleMap.MAP_TYPE_HYBRID);

        //Add markers to the map from resultsList
        for (int i = 0; i < resultsList.size(); i++)    {
            Double latitude = Double.valueOf(resultsList.get(i).get("Lat"));
            Double longitude = Double.valueOf(resultsList.get(i).get("Lng"));
            String mname = resultsList.get(i).get("AgencyName");
            LatLng posit = new LatLng(latitude, longitude);
            map.addMarker(new MarkerOptions()
            .position(posit)
            .title(mname));
        }

        return rootView;
    }

}

如果有帮助的话，这里的代码来自MyHomeFragment，搜索结果存储在ArrayList中

package com.wny.wecare.fragment;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnKeyListener;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.TextView;
import android.widget.Toast;

import com.wny.wecare.MainActivity;
import com.wny.wecare.R;
import com.wny.wecare.handler.JSONParser;

public class HomeFragment extends Fragment implements OnItemSelectedListener, OnClickListener{

    private OnFragmentInteractionListener mListener;

    private Spinner spinner;
    private Button btnSubmit;

    private static final String[] list={"Alden", "Amherst", "Angola",
        "Blasdell", "Boston", "Bowmansville", "Buffalo", "Cheektowaga", "Clarence",
        "Depew", "Derby", "East Aurora", "Eden", "Elma", "Getzville", "Gowanda",
        "Grand Island", "Holland", "Irving", "Kenmore", "Lackawanna", "Lake View",
        "Lancaster", "Lawtons", "North Collins", "Orchard Park", "Snyder", "Springville",
        "Tonawanda", "West Seneca", "Williamsville"};

    // Setup ArrayList from main activity to store results
    ArrayList<Map<String, String>> resultsList = new ArrayList<Map<String,  String>>();

    // Creating JSON Parser object
    JSONParser jParser = new JSONParser();

    // products JSONArray
    JSONArray agency = null;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.fragment_home, container, false);

        btnSubmit = (Button) rootView.findViewById(R.id.town_search);
        btnSubmit.setOnClickListener(this);
        spinner =(Spinner)rootView.findViewById(R.id.spinner);
        spinner.setOnItemSelectedListener(this);

        ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_spinner_item,list);
        dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(dataAdapter);

        return rootView;

    }

    // Check if parent activity implements the interface
    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);
        try {
            mListener =
                    (OnFragmentInteractionListener)  activity;
        } catch (ClassCastException e) {
            throw new ClassCastException(activity.toString()
                    + " must implement OnFragmentInteractionListener");
        }
    }

    //add items into spinner dynamically
    /*public void addItemsOnSpinner2(View v) {
        addItemsOnSpinner2(v);
        final List<String> list = new ArrayList<String>();
        list.add("list 1");
        list.add("list 2");
        list.add("list 3");
        ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_spinner_item,list);

        dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

    }*/

    @Override
    public void onClick(View v) {
        switch (v.getId()){
        case R.id.town_search:
            String town = (String) spinner.getSelectedItem().toString();
            agencySearch(town);
            mListener.onFragmentButton();
            break;
        case R.id.zip_search:
            String strZip  = ((EditText) v.findViewById(R.id.txt_zip)).getText().toString().trim();
            int zip = Integer.parseInt(strZip);
            agencySearch(zip);
            mListener.onFragmentButton();
            break;
            /*case R.id.btn_location:
            String strZip = v.findViewById(R.id.txt_zip).toString();
            int zip = Integer.parseInt(strZip);
            agencySearch(zip);
            mListener.onFragmentButton();
            break;*/
        }
    }

    @Override
    public void onItemSelected(AdapterView<?> parent,
            View v, int position, long id) {

    }

    @Override
    public void onNothingSelected(AdapterView<?> parent) {
        // TODO Auto-generated method stub

    }

    public void agencySearch(String tsearch)    {
        // Setting the URL for the Search by Town
        String url_search_agency = "http://www.infinitycodeservices.com/get_agency_by_city.php";
        // Building parameters for the search
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("City", tsearch));

        // Getting JSON string from URL
        JSONArray json = jParser.getJSONFromUrl(url_search_agency, params);

        for (int i = 0; i < json.length(); i++) {
            HashMap<String, String> map = new HashMap<String, String>();

            try {
                JSONObject c = (JSONObject) json.get(i);
                //Fill map
                Iterator iter = c.keys();
                while(iter.hasNext())   {
                    String currentKey = (String) iter.next();
                    map.put(currentKey, c.getString(currentKey));
                }
                resultsList.add(map);

            }
            catch (JSONException e) {
                e.printStackTrace();

            }

        };

        MainActivity.setResultsList(resultsList);

    }

    public void agencySearch(int zsearch)   {
        // Setting the URL for the Search by Zip
        String url_search_agency = "http://www.infinitycodeservices.com/get_agency_by_zip.php";
        // Building parameters for the search
        List<NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("zip", Integer.toString(zsearch)));

        // Getting JSON string from URL
        JSONArray json = jParser.getJSONFromUrl(url_search_agency, params);

        for (int i = 0; i < json.length(); i++) {
            HashMap<String, String> map = new HashMap<String, String>();

            try {
                JSONObject c = (JSONObject) json.get(i);
                //Fill map
                Iterator iter = c.keys();
                while(iter.hasNext())   {
                    String currentKey = (String) iter.next();
                    map.put(currentKey, c.getString(currentKey));
                }
                resultsList.add(map);

            }
            catch (JSONException e) {
                e.printStackTrace();

            }

        };

        MainActivity.setResultsList(resultsList);

    }


}

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若地图并没有显示意味着你们的谷歌地图键有问题……好的，我会检查一下。listView怎么样？这也显示为空白。更正了应用程序的Maps API键，我在片段中得到了一张地图。但是，我仍然没有在地图上得到任何标记，也没有在listView中得到结果。我想这一定是我从ArrayList中读取数据的方式有问题，但我似乎看不出问题所在。