我正在开发一个包含谷歌地图的应用程序。我想在地图上添加标记/指针。指针将从接收到的数据中添加。因此，如果数据库中有 3 行，那么它应该向地图添加 3 个标记，其中 LatLng 和行的名称。
我可以手动添加标记，但我希望它循环执行。因此，对于每一行 -> 在地图上添加一个标记。
如何才能做到这一点？
我的活动如下。
public class MapsActivity extends Activity {
private MainMapFragement mapFragment;
private HashMap<Marker, EventInfo> eventMarkerMap;
private LatLng mPosition;
Geocoder geocoder;
String bestProvider;
List<Address> user = null;
double lat, lng;
private ProgressDialog pDialog;
JSONParser jParser = new JSONParser();
ArrayList<HashMap<String, String>> productsList;
private static String url_all_products = "http://000100023.host56.com/db_all.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
private static final String TAG_PRODUCTS = "locations";
private static final String TAG_PID = "id";
private static final String TAG_NAME = "name";
// products JSONArray
JSONArray products = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
ActionBar abs = getActionBar();
abs.setTitle(R.string.activity_title_map);
abs.setDisplayHomeAsUpEnabled(true);
mapFragment = new MainMapFragement();
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.add(R.id.map, mapFragment);
ft.commit();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
protected void onStart() {
super.onStart();
new LoadAllLocations().execute();
setCurrentLocationSpot();
}
private void setCurrentLocationSpot() {
LocationManager lm = (LocationManager) MapsActivity.this.getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
bestProvider = lm.getBestProvider(criteria, false);
Location location = lm.getLastKnownLocation(bestProvider);
if (location == null){
Toast.makeText(MapsActivity.this,"Location Not found",Toast.LENGTH_LONG).show();
}else{
geocoder = new Geocoder(MapsActivity.this);
try {
user = geocoder.getFromLocation(location.getLatitude(), location.getLongitude(), 1);
lat=(double)user.get(0).getLatitude();
lng=(double)user.get(0).getLongitude();
mPosition = new LatLng(lat, lng);
GoogleMap mGap = ((MapFragment) getFragmentManager()
.findFragmentById(R.id.map)).getMap();
mGap.setMyLocationEnabled(true);
mGap.animateCamera(CameraUpdateFactory.newLatLngZoom(mPosition, 13));
}catch (Exception e) {
e.printStackTrace();
}
}
}
private void setUpEventSpots() {
EventInfo firstEventInfo = new EventInfo(new LatLng(60.39341189999999, 5.322973699999999), "Right now - event", new Date(), null);
EventInfo secondEventInfo = new EventInfo(new LatLng(51.25, 4.15), "Future Event", new Date(1032, 5, 25), null);
Marker firstMarker = mapFragment.placeMarker(firstEventInfo);
Marker secondMarker = mapFragment.placeMarker(secondEventInfo);
eventMarkerMap = new HashMap<Marker, EventInfo>();
eventMarkerMap.put(firstMarker, firstEventInfo);
eventMarkerMap.put(secondMarker, secondEventInfo);
mapFragment.getMap().setOnInfoWindowClickListener(new OnInfoWindowClickListener() {
@Override
public void onInfoWindowClick(Marker marker) {
EventInfo eventInfo = eventMarkerMap.get(marker);
Toast.makeText(getBaseContext(),
"The date of " + eventInfo.getName() + " is " + eventInfo.getSomeDate().toLocaleString(),
Toast.LENGTH_LONG).show();
}
});
}
class LoadAllLocations extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
@Override
protected void onPreExecute() {
super.onPreExecute();
//pDialog = new ProgressDialog(MapsActivity.this);
//pDialog.setMessage("Loading locations. Please wait...");
//pDialog.setIndeterminate(false);
//pDialog.setCancelable(false);
//pDialog.show();
}
/**
* getting All products from url
* */
protected String doInBackground(String... args) {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
// getting JSON string from URL
JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);
// Check your log cat for JSON reponse
Log.d("All Products: ", json.toString());
try {
// Checking for SUCCESS TAG
int success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// products found
// Getting Array of Products
products = json.getJSONArray(TAG_PRODUCTS);
// looping through All Products
for (int i = 0; i < products.length(); i++) {
JSONObject c = products.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_PID);
String name = c.getString(TAG_NAME);
setUpEventSpots();
// creating new HashMap
//HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
//map.put(TAG_PID, id);
//map.put(TAG_NAME, name);
// adding HashList to ArrayList
//productsList.add(map);
}
} else {
// no products found
// Launch Add New product Activity
//Intent i = new Intent(getApplicationContext(),
// NewProductActivity.class);
// Closing all previous activities
//i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
//startActivity(i);
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
}
}
日志猫：
11-14 21:52:30.391: E/AndroidRuntime(30921): FATAL EXCEPTION: AsyncTask #1
11-14 21:52:30.391: E/AndroidRuntime(30921): Process: com.spxc.nightclubratings, PID: 30921
11-14 21:52:30.391: E/AndroidRuntime(30921): java.lang.RuntimeException: An error occured while executing doInBackground()
11-14 21:52:30.391: E/AndroidRuntime(30921): at android.os.AsyncTask$3.done(AsyncTask.java:300)
11-14 21:52:30.391: E/AndroidRuntime(30921): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
11-14 21:52:30.391: E/AndroidRuntime(30921): at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
11-14 21:52:30.391: E/AndroidRuntime(30921): at java.util.concurrent.FutureTask.run(FutureTask.java:242)
11-14 21:52:30.391: E/AndroidRuntime(30921): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
11-14 21:52:30.391: E/AndroidRuntime(30921): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
11-14 21:52:30.391: E/AndroidRuntime(30921): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
11-14 21:52:30.391: E/AndroidRuntime(30921): at java.lang.Thread.run(Thread.java:841)
11-14 21:52:30.391: E/AndroidRuntime(30921): Caused by: java.lang.IllegalStateException: Not on the main thread
11-14 21:52:30.391: E/AndroidRuntime(30921): at maps.aq.o.b(Unknown Source)
11-14 21:52:30.391: E/AndroidRuntime(30921): at maps.ak.g.b(Unknown Source)
11-14 21:52:30.391: E/AndroidRuntime(30921): at maps.af.al.a(Unknown Source)
11-14 21:52:30.391: E/AndroidRuntime(30921): at clz.onTransact(SourceFile:167)
11-14 21:52:30.391: E/AndroidRuntime(30921): at android.os.Binder.transact(Binder.java:361)
11-14 21:52:30.391: E/AndroidRuntime(30921): at com.google.android.gms.maps.internal.IGoogleMapDelegate$a$a.addMarker(Unknown Source)
11-14 21:52:30.391: E/AndroidRuntime(30921): at com.google.android.gms.maps.GoogleMap.addMarker(Unknown Source)
11-14 21:52:30.391: E/AndroidRuntime(30921): at com.spxc.nightclubratings.adapter.MainMapFragement.placeMarker(MainMapFragement.java:10)
11-14 21:52:30.391: E/AndroidRuntime(30921): at com.spxc.nightclubratings.MapsActivity.setUpEventSpots(MapsActivity.java:126)
11-14 21:52:30.391: E/AndroidRuntime(30921): at com.spxc.nightclubratings.MapsActivity.access$1(MapsActivity.java:122)
11-14 21:52:30.391: E/AndroidRuntime(30921): at com.spxc.nightclubratings.MapsActivity$LoadAllLocations.doInBackground(MapsActivity.java:189)
11-14 21:52:30.391: E/AndroidRuntime(30921): at com.spxc.nightclubratings.MapsActivity$LoadAllLocations.doInBackground(MapsActivity.java:1)
11-14 21:52:30.391: E/AndroidRuntime(30921): at android.os.AsyncTask$2.call(AsyncTask.java:288)
11-14 21:52:30.391: E/AndroidRuntime(30921): at java.util.concurrent.FutureTask.run(FutureTask.java:237)
11-14 21:52:30.391: E/AndroidRuntime(30921): ... 4 more
任何帮助深表感谢！