Google 地图地点标记未显示

Google Maps Place marker not displaying

我正在尝试显示我使用 google 地图地点 api 获得的地点的位置。但是我的搜索结果的标记没有显示在地图上。而且我似乎找不到问题所在。下面是我的源代码副本和我的 logcat 日志。任何帮助将不胜感激。提前谢谢你:) .

我的主要活动

public class MainActivity extends FragmentActivity implements LocationListener, GoogleMap.OnMapClickListener {

        GoogleMap mGoogleMap;
        Spinner mSprPlaceType;

        String[] mPlaceType=null;
        String[] mPlaceTypeName=null;

        double mLatitude=0;
        double mLongitude=0;
        LatLng center;

        @Override
        protected void onCreate(Bundle savedInstanceState) {


            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);

            // Array of place types
            mPlaceType = getResources().getStringArray(R.array.place_type);

            // Array of place type names
            mPlaceTypeName = getResources().getStringArray(R.array.place_type_name);

            // Creating an array adapter with an array of Place types
            // to populate the spinner
            ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, mPlaceTypeName);

            // Getting reference to the Spinner
            mSprPlaceType = (Spinner) findViewById(R.id.spr_place_type);

            // Setting adapter on Spinner to set place types
            mSprPlaceType.setAdapter(adapter);

            Button btnFind;

            // Getting reference to Find Button
            btnFind = ( Button ) findViewById(R.id.btn_find);


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


            if(status!=ConnectionResult.SUCCESS){ // Google Play Services are not available

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

            }else { // Google Play Services are available

                // Getting reference to the SupportMapFragment
                SupportMapFragment fragment = ( SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.map);


                // Getting Google Map

                mGoogleMap = fragment.getMap();
                mGoogleMap.setOnMapClickListener(this);
                mGoogleMap.getUiSettings().isCompassEnabled();
                mGoogleMap.getUiSettings().setZoomControlsEnabled(true);
                mGoogleMap.getUiSettings().setScrollGesturesEnabled(true);
                mGoogleMap.getUiSettings().setMapToolbarEnabled(true);
                mGoogleMap.setMyLocationEnabled(true);

                // Enabling MyLocation in Google Map
                mGoogleMap.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 From GPS
                Location location = locationManager.getLastKnownLocation(provider);

                if(location!=null){

                    onLocationChanged(location);

                }




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

                // Setting click event lister for the find button
                btnFind.setOnClickListener(new OnClickListener() {

                    @Override
                    public void onClick(View v) {


                        int selectedPosition = mSprPlaceType.getSelectedItemPosition();
                        String type = mPlaceType[selectedPosition];


                        StringBuilder sb = new StringBuilder("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
                        sb.append("location="+mLatitude+","+mLongitude);
                        sb.append("&radius=5000");
                        sb.append("&types="+type);
                        sb.append("&sensor=true");
                        sb.append("&key=MY_API_KEY");


                        // Creating a new non-ui thread task to download Google place json data
                        PlacesTask placesTask = new PlacesTask();

                        // Invokes the "doInBackground()" method of the class PlaceTask
                        Log.d("url",sb.toString());
                        placesTask.execute(sb.toString());


                    }
                });

            }

        }

        /** A method to download json data from url */
        private String downloadUrl(String strUrl) throws IOException{
            String data = "";
            InputStream iStream = null;
            HttpURLConnection urlConnection = null;
            try{
                URL url = new URL(strUrl);


                // Creating an http connection to communicate with url
                urlConnection = (HttpURLConnection) url.openConnection();

                // Connecting to url
                urlConnection.connect();

                // Reading data from url
                iStream = urlConnection.getInputStream();

                BufferedReader br = new BufferedReader(new InputStreamReader(iStream));

                StringBuffer sb  = new StringBuffer();

                String line = "";
                while( ( line = br.readLine())  != null){
                    sb.append(line);
                }

                data = sb.toString();

                br.close();

            }catch(Exception e){
                Log.d("Exception while downloading url", e.toString());
            }finally{
                iStream.close();
                urlConnection.disconnect();
            }

            return data;
        }

        @Override
        public void onMapClick(LatLng latLng) {
            center = mGoogleMap.getCameraPosition().target;
            //  Toast.makeText(MainActivity.this, center.toString(), Toast.LENGTH_LONG).show();
            mLatitude= center.latitude;
            mLongitude=center.longitude;

        }


        /** A class, to download Google Places */
        private class PlacesTask extends AsyncTask<String, Integer, String>{

            String data = null;

            // Invoked by execute() method of this object
            @Override
            protected String doInBackground(String... url) {
                try{
                    data = downloadUrl(url[0]);
                }catch(Exception e){
                    Log.d("Background Task",e.toString());
                }
                return data;
            }

            // Executed after the complete execution of doInBackground() method
            @Override
            protected void onPostExecute(String result){
                ParserTask parserTask = new ParserTask();

                // Start parsing the Google places in JSON format
                // Invokes the "doInBackground()" method of the class ParseTask
                parserTask.execute(result);
            }

        }

        /** A class to parse the Google Places in JSON format */
        private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String,String>>>{

            JSONObject jObject;

            // Invoked by execute() method of this object
            @Override
            protected List<HashMap<String,String>> doInBackground(String... jsonData) {

                List<HashMap<String, String>> places = null;
                PlaceJSONParser placeJsonParser = new PlaceJSONParser();

                try{
                    jObject = new JSONObject(jsonData[0]);

                    /** Getting the parsed data as a List construct */
                    places = placeJsonParser.parse(jObject);

                }catch(Exception e){
                    Log.d("Exception",e.toString());
                }
                return places;
            }

            // Executed after the complete execution of doInBackground() method
            @Override
            protected void onPostExecute(List<HashMap<String,String>> list){

                // Clears all the existing markers
                mGoogleMap.clear();

                for(int i=0;i<list.size();i++){

                    // Creating a marker
                    MarkerOptions markerOptions = new MarkerOptions();

                    // Getting a place from the places list
                    HashMap<String, String> hmPlace = list.get(i);

                    // Getting latitude of the place
                    double lat = Double.parseDouble(hmPlace.get("lat"));

                    // Getting longitude of the place
                    double lng = Double.parseDouble(hmPlace.get("lng"));

                    // Getting name
                    String name = hmPlace.get("place_name");

                    // Getting vicinity
                    String vicinity = hmPlace.get("vicinity");

                    LatLng latLng = new LatLng(lat, lng);

                    // Setting the position for the marker
                    markerOptions.position(latLng);

                    // Setting the title for the marker.
                    //This will be displayed on taping the marker
                    markerOptions.title(name + " : " + vicinity);

                    // Placing a marker on the touched position
                    mGoogleMap.addMarker(markerOptions);

                }

            }

        }



        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu_main; this adds items to the action bar if it is present.
            getMenuInflater().inflate(R.menu.menu_main, menu);
            return true;
        }

        @Override
        public void onLocationChanged(Location location) {
            mLatitude = location.getLatitude();
            mLongitude = location.getLongitude();
            LatLng latLng = new LatLng(mLatitude, mLongitude);

            mGoogleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
            mGoogleMap.animateCamera(CameraUpdateFactory.zoomTo(12));

        }

        @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

        }
    }

我的 JSONParser :

public class JSONParser {

    /** Receives a JSONObject and returns a list */
    public List<HashMap<String,String>> parse(JSONObject jObject){

        JSONArray jPlaces = null;
        try {
            /** Retrieves all the elements in the 'places' array */
            jPlaces = jObject.getJSONArray("results");
        } catch (JSONException e) {
            e.printStackTrace();
        }
        /** Invoking getPlaces with the array of json object
         * where each json object represent a place
         */
        return getPlaces(jPlaces);
    }


    private List<HashMap<String, String>> getPlaces(JSONArray jPlaces){
        int placesCount = jPlaces.length();
        List<HashMap<String, String>> placesList = new ArrayList<HashMap<String,String>>();
        HashMap<String, String> place = null;

        /** Taking each place, parses and adds to list object */
        for(int i=0; i<placesCount;i++){
            try {
                /** Call getPlace with place JSON object to parse the place */
                place = getPlace((JSONObject)jPlaces.get(i));
                placesList.add(place);

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

        return placesList;
    }

    /** Parsing the Place JSON object */
    private HashMap<String, String> getPlace(JSONObject jPlace){

        HashMap<String, String> place = new HashMap<String, String>();
        String placeName = "-NA-";
        String vicinity="-NA-";
        String latitude="";
        String longitude="";


        try {
            // Extracting Place name, if available
            if(!jPlace.isNull("name")){
                placeName = jPlace.getString("name");
            }

            // Extracting Place Vicinity, if available
            if(!jPlace.isNull("vicinity")){
                vicinity = jPlace.getString("vicinity");
            }

            latitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lat");
            longitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lng");


            place.put("place_name", placeName);
            place.put("vicinity", vicinity);
            place.put("lat", latitude);
            place.put("lng", longitude);


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

我的activity_main:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <Spinner
        android:id="@+id/spr_place_type"
        android:layout_width="200dp"
        android:layout_height="60dp"
        android:gravity="center"

         />

    <Button
        android:id="@+id/btn_find"
        android:layout_width="200dp"
        android:layout_height="60dp"
        android:layout_alignParentTop="true"
        android:layout_toRightOf="@id/spr_place_type"
        android:text="@string/str_btn_find" />

    <fragment xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/map"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/spr_place_type"
        class="com.google.android.gms.maps.SupportMapFragment" />

    <ImageView
        android:layout_width="30dp"
        android:layout_height="50dp"
        android:id="@+id/imageView"
        android:src="@drawable/location"
        android:layout_centerVertical="true"
        android:layout_centerHorizontal="true" />
</RelativeLayout>

还有我的 logcat:

private void getParticularTypeLocation(String selType){
    StringBuilder googlePlacesUrl = new StringBuilder("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
    googlePlacesUrl.append("location=" + latitude + "," + longitude);
    googlePlacesUrl.append("&radius=" + 5000);
    googlePlacesUrl.append("&types=" + selType);
    googlePlacesUrl.append("&sensor=true");
    googlePlacesUrl.append("&key=" + GOOGLE_API_KEY);

    GooglePlacesReadTask googlePlacesReadTask = new GooglePlacesReadTask();
    Object[] toPass = new Object[2];
    toPass[0] = googlePlacesUrl.toString();
    toPass[1] = BitmapDescriptorFactory.HUE_VIOLET;
    googlePlacesReadTask.execute(toPass);

    MarkerOptions marker = new MarkerOptions().position(
            new LatLng(randomLocation[0], randomLocation[1]))
            .title("Current Location");

    marker.icon(BitmapDescriptorFactory
            .defaultMarker(BitmapDescriptorFactory.HUE_GREEN));

    googleMap.addMarker(marker);

    CameraPosition cameraPosition = new CameraPosition.Builder()
    .target(new LatLng(randomLocation[0],
            randomLocation[1])).zoom(13).build();
    googleMap.animateCamera(CameraUpdateFactory
            .newCameraPosition(cameraPosition));
}

您可以参考此代码,这将在 google 地图中获取相关位置。

将字符串输入作为医院、酒店、警察局、公园等类型,

希望对你有所帮助