java标记未使用JSON显示在google地图中
我试图从JSON解析中添加标记。但是地图上没有这些标记。有人能帮我吗?这是我的密码:
主要活动。爪哇
package com.hasibhasan.sampletask;
import java.util.ArrayList;
import org.json.JSONArray;
import org.json.JSONObject;
import 安卓.os.AsyncTask;
import 安卓.os.Bundle;
import 安卓.support.v7.app.ActionBarActivity;
import com.google.安卓.gms.maps.GoogleMap;
import com.google.安卓.gms.maps.MapFragment;
import com.google.安卓.gms.maps.model.LatLng;
import com.google.安卓.gms.maps.model.MarkerOptions;
public class MainActivity extends ActionBarActivity {
private GoogleMap googlemap;
private static String TAG_POSTS = "posts";
private static String TAG_DRIVER = "driver";
private static String TAG_ID = "id";
private static String TAG_LATITUDE = "lat";
private static String TAG_LONGITUDE = "lon";
private static String TAG_DATETIME = "recorded_datetime";
private static String TAG_USERID = "user_id";
private static String TAG_STATE = "cabby_state";
private static String TAG_VTYPE = "vehicleType";
private static String TAG_DRIVERNAME = "driver_name";
private static String TAG_PICNAME = "pic_name";
private static String TAG_RATING = "rating";
private static String TAG_CARMODEL = "car_model";
private static String TAG_NUMBERSIT = "number_sit";
private static String TAG_DISTANCE = "distance";
private static String TAG_OPERATOR = "operator";
private static String TAG_NEARESTDISTANCE = "nearest_distance";
private static String TAG_NDISTANCE = "distance";
private static String TAG_TIME = "time";
private static String TAG_CARMODELS = "car_models";
ArrayList<Taxi> taxi;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
taxi = new ArrayList<Taxi>();
new ParseJSONTask().execute();
googlemap = ((MapFragment) getFragmentManager().findFragmentById(
R.id.map)).getMap();
}
private class ParseJSONTask extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... params) {
WebServiceHandler webServiceHandler = new WebServiceHandler();
String jsonstr = webServiceHandler
.getJSONData("http://54.186.247.213/unicabi/mobileservice/CurrentLocationService.php");
try {
JSONObject jsonObject = new JSONObject(jsonstr);
JSONArray postJson = jsonObject.getJSONArray(TAG_POSTS);
for (int i = 0; i < postJson.length(); i++) {
Taxi aTaxi = new Taxi();
JSONObject postObject = postJson.getJSONObject(i);
aTaxi.lat = postObject.getString(TAG_LATITUDE);
aTaxi.lon = postObject.getString(TAG_LONGITUDE);
aTaxi.driver_name = postObject.getString(TAG_DRIVERNAME);
taxi.add(aTaxi);
double lati = Double.parseDouble(aTaxi.lat);
double lon = Double.parseDouble(aTaxi.lon);
googlemap.addMarker(new MarkerOptions().title(
aTaxi.driver_name).position(new LatLng(lati, lon)));
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
}
}
}
出租车。java(模型类)
package com.hasibhasan.sampletask;
public class Taxi {
public String posts = "";
public String success = "";
public String driver = "";
public String id = "";
public String lat = "";
public String lon = "";
public String recorded_datetime = "";
public String vehicleType = "";
public String driver_name = "";
public String pic_name = "";
public String rating = "";
public String car_model = "";
public String number_sit = "";
public String distance = "";
public String operator = "";
public String nearest_distance = "";
public String car_models = "";
}
Webservicehandler。爪哇
package com.hasibhasan.sampletask;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
public class WebServiceHandler {
public WebServiceHandler() {
}
public String getJSONData(String url) {
String response = null;
DefaultHttpClient httpclient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
HttpEntity httpEntity = null;
HttpResponse httpResponse = null;
try {
httpResponse = httpclient.execute(httpGet);
httpEntity = httpResponse.getEntity();
response = EntityUtils.toString(httpEntity);
} catch (Exception e) {
e.printStackTrace();
}
return response;
}
}
# 1 楼答案
您正在尝试从非UI线程更新UI。这是不允许的,通常应引发异常。最好使用自定义侦听器从
onPostExecute
方法将滑行列表传递到UI线程。 创建自定义侦听器:向asyncTask添加构造函数,如下所示:
并在onPostExecute中返回列表:
并重写onCreate方法:
# 2 楼答案
将
array of MarkerOptions
传递给在UI线程上运行的onPostExecute
方法。您可以将标记添加到地图中。例如: