Question

我想从服务器检索所有纬度和经度位置，该位置已经存储并显示在谷歌地图标记中

我的服务器文件：http://plantnow.net16.net/googlemaplocations.php

但是我只能在google地图中获得一个标记，即treeid = 2，其余位置在地图中没有显示任何标记。

我在下面的代码中出错了，请帮助我！

   btMap.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            String search = String.valueOf(inputSearch.getSelectedItem()).toString();

            mMap = mMapView.getMap();

            mMap.clear();

            //getSelectedLocations(search);

            Toast.makeText(getActivity().getApplicationContext(), "Locations of " + search + " trees", Toast.LENGTH_LONG).show();


            if (search.equals("All Locations")) {
                double latitude = 0;
                double longitude = 0;
                String mark;

                getLocations();

                Toast.makeText(getActivity().getApplicationContext(), "All trees locations ", Toast.LENGTH_LONG).show();



            } else {

                Toast.makeText(getActivity().getApplicationContext(), "Location are not available ", Toast.LENGTH_LONG).show();
            }

        }
    });

    return v;
}

我正在使用排球库从服务器上搜索位置。

 private void getLocations() {
    // Tag used to cancel the request
    String tag_string_req = "req_location";

   // pDialog.setMessage("Logging in ...");
   // showDialog();

    StringRequest strReq = new StringRequest(Request.Method.POST,
            AppConfig.URL_MAPLOCATION, new Response.Listener<String>() {

        @Override
        public void onResponse(String response) {
            Log.d(TAG, "Location Response: " + response.toString());
            hideDialog();

            try {
                JSONObject jObj = new JSONObject(response);
                boolean error = jObj.getBoolean("error");
                List<Marker> markers = new ArrayList<Marker>();

                // Check for error node in json
                if (!error) {

                    JSONObject location = jObj.getJSONObject("tree");

                    for (int i = 0; i < location.length(); i++) {

                        String treeid = location.getString("treeid");
                        String treespecies = location.getString("treespecies");
                        Double treelatitude = location.getDouble("treelatitude");
                        Double treelongitude = location.getDouble("treelongitude");

                        LatLng latlng = new LatLng(treelatitude, treelongitude);

                        Marker marker =  mMap.addMarker(new MarkerOptions().title(treeid)
                                        .position(new LatLng(treelatitude, treelongitude))
                        );
                           markers.add(marker);
                        // Moving CameraPosition to last clicked position
                        mMap.moveCamera(CameraUpdateFactory.newLatLng(latlng));

                        // Setting the zoom level in the map on last position is clicked
                        mMap.animateCamera(CameraUpdateFactory.newLatLng(latlng));

                        mMap.animateCamera(CameraUpdateFactory.zoomTo(2));

                    }

                    // Launch main activity

                } else {
                    // Error in login. Get the error message
                    String errorMsg = jObj.getString("error_msg");
                    Toast.makeText(getActivity().getApplicationContext(),
                            errorMsg, Toast.LENGTH_LONG).show();
                }
            } catch (JSONException e) {
                // JSON error
                e.printStackTrace();
                Toast.makeText(getActivity().getApplicationContext(), "Json error: " + e.getMessage(), Toast.LENGTH_LONG).show();
            }

        }
    }, new Response.ErrorListener() {

        @Override
        public void onErrorResponse(VolleyError error) {
            Log.e(TAG, "Login Error: " + error.getMessage());
            Toast.makeText(getActivity().getApplicationContext(),
                    error.getMessage(), Toast.LENGTH_LONG).show();
            hideDialog();
        }
    }) {



    };

    // Adding request to request queue
    AppController.getInstance().addToRequestQueue(strReq, tag_string_req);
}

我的PHP代码：

<?php
define('__ROOT__', dirname(dirname(__FILE__))); 
require_once(__ROOT__.'/public_html/Config.php');




 // Connecting to mysql database
    $mysqli = new mysqli(DB_HOST, DB_USER, DB_PASSWORD, DB_DATABASE);

   // json response array
       $response = array("error" => FALSE);




// get the tree details for google map marker
if($stmt = $mysqli->query("SELECT * FROM tree where `treecondition` IN ( 'Balanced', 'Healthy', 'Imbalance', 'Dangerous', 'Transplanted', 'Dieseased')")){



 if ($stmt->num_rows) {


       while($tree = $stmt->fetch_assoc()) {

        $response["error"] = FALSE;

        $response ["tree"] ["treeid"] = $tree['treeid'];
        $response ["tree"] ["treespecies"] = $tree['treespecies'];
        $response ["tree"] ["treelatitude"] = $tree['treelatitude'];
        $response ["tree"] ["treelongitude"] = $tree['treelongitude'];
        echo json_encode($response),'<br>';
          } 
           }else {
     // user is not found with the credentials
         $response["error"] = TRUE;
       $response["error_msg"] = "Tree list view credentials are wrong. Please try again!";
        echo json_encode($response);
       }
         $mysqli->close();
            }

Answer 1

将所有对象添加到列表中，只调用json_encode()一次。

$response = array();
while($tree = $stmt->fetch_assoc()) {
    $treeItem = array();
    $treeItem["treeid"] = $tree['treeid'];
    $treeItem["treespecies"] = $tree['treespecies'];
    $treeItem["treelatitude"] = $tree['treelatitude'];
    $treeItem["treelongitude"] = $tree['treelongitude'];
    $response[] = $treeItem;
    // Might just be easier to do this instead
    // $response[] = $tree;
}

echo json_encode($response);

然后在你的android代码中，迭代列表。

JSONArray jTreeList = new JSONArray(response);
for (int i = 0; i < jTreeList.length(); i++) {
    JSONObject jTreeObj = jTreeList.getJSONObject(i);
    String treeid = jTreeObj.getString("treeid");
    // read rest of fields
    // create marker, etc
}

从服务器检索位置并使用排球库在Google地图标记中显示？

1 个答案: