Question

我想使用存储在数据库中的值显示多个标记。但我只能在地图中看到当前位置。我可以知道我犯了什么错误。

公共类MainActivity extends FragmentActivity实现了LocationListener {

GoogleMap googleMap;
JSONObject jsonobject;
JSONArray jsonarray;
Float Lati,Longi;
ProgressDialog mProgressDialog;
ArrayList<User> emp;
ArrayList<String> Latitude;
ArrayList<String> Longitude;
ArrayList<HashMap<String, Float>> oslist = new ArrayList<HashMap<String, Float>>();
HashMap<String, Float> map = new HashMap<String, Float>();

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Getting Google Play availability status
    int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getBaseContext());

    // Showing status
    if(status!=ConnectionResult.SUCCESS){ 

        int requestCode = 10;
        Dialog dialog = GooglePlayServicesUtil.getErrorDialog(status, this, requestCode);
        dialog.show();

    }else { // Google Play Services are available   

        // Getting reference to the SupportMapFragment of activity_main.xml
        SupportMapFragment fm = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);

        // Getting GoogleMap object from the fragment
        googleMap = fm.getMap();

        // Enabling MyLocation Layer of Google Map
        googleMap.setMyLocationEnabled(true);               


         // Getting LocationManager object from System Service LOCATION_SERVICE
        LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);

        // Creating a criteria object to retrieve provider
        Criteria criteria = new Criteria();

        // Getting the name of the best provider
        String provider = locationManager.getBestProvider(criteria, true);

        // Getting Current Location
        Location location = locationManager.getLastKnownLocation(provider);
        new DownJSON().execute();
        if(location!=null){
                onLocationChanged(location);

        }

        locationManager.requestLocationUpdates(provider, 20000, 0, this);
    }
}

@Override
public void onLocationChanged(Location location) {

    TextView tvLocation = (TextView) findViewById(R.id.tv_location);

    // Getting latitude of the current location
    double latitude = location.getLatitude();

    // Getting longitude of the current location
    double longitude = location.getLongitude();     

    // Creating a LatLng object for the current location
    LatLng latLng = new LatLng(latitude, longitude);

    // Showing the current location in Google Map
    googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));

    // Zoom in the Google Map
    googleMap.animateCamera(CameraUpdateFactory.zoomTo(15));        


    // Setting latitude and longitude in the TextView tv_location
    tvLocation.setText("Latitude:" +  latitude  + ", Longitude:"+ longitude );      

}

@Override
public void onProviderDisabled(String provider) {
    // TODO Auto-generated method stub      
}

@Override
public void onProviderEnabled(String provider) {
    // TODO Auto-generated method stub      
}

@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
    // TODO Auto-generated method stub      
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}
private class DownJSON extends AsyncTask<Void, Void, Void> {

    protected Void doInBackground(Void... arg0) {
        // TODO Auto-generated method stub

float zoom=0;
emp = new ArrayList<User>();    
Log.d("Inside DownJson","DownJson");

jsonobject = JSONParser.getJSONfromURLL("JSON URL");

try {
    jsonarray = jsonobject.getJSONArray("User");
    Log.d("Latitude",jsonarray.toString());

    for (int i = 0; i <  jsonarray.length(); i++) {
        jsonobject = jsonarray.getJSONObject(i);

        User e = new User();
        Float Lati =Float.valueOf(jsonobject.optString("Latitude"));
        Log.d("Latitude",jsonobject.optString("Latitude"));
        Float Longi =Float.valueOf(jsonobject.optString("Longitude"));
        Log.d("Latitude",jsonobject.optString("Longitude"));

        map.put("lati", Lati);
        map.put("longi", Longi);

    }
}catch (JSONException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}
return null;

}

    protected void onPostExecute(Void args)
    {   
        for (String key : map.keySet()) {
             Log.d("LatituInFor",String.valueOf(map.get("lati")));
             Log.d("LongInFor",String.valueOf(map.get("longi")));
             LatLng pinLocation = new LatLng(Float.valueOf(map.get("longi")),Float.valueOf(map.get("longi")));
                Marker storeMarker = googleMap.addMarker(new MarkerOptions()
                    .position(pinLocation)
                        );
        }
    }

private void drawMarker(LatLng point){
    // Creating an instance of MarkerOptions
    MarkerOptions markerOptions = new MarkerOptions();                  

    // Setting latitude and longitude for the marker
    markerOptions.position(point);

    // Adding marker on the Google Map
    googleMap.addMarker(markerOptions);         
}
        }

}

Answer 1

可能在这里是问题

LatLng pinLocation = new LatLng(Float.valueOf(map.get("longi")),Float.valueOf(map.get("longi")));"

你在（map.get（“longi”）中使用了“longi” for Latitute和Longitude

Android谷歌地图不会显示多个标记

1 个答案: