Android Google Maps: не удалось запустить Activity ComponentInfo MainActivity}: java.lang.NullPointerException

Question

Я делал приложение в android, чтобы получить мои соседние места, и когда я попытался запустить, я сделал все, но получил это исключение, и я не знаю, что является причиной, обуславливающей это исключение

MainActivity

package com.gas; 

public class MainActivity extends Activity implements LocationListener{ 

    GoogleMap mGoogleMap; 
    GoogleMap map; 
    Spinner mSprPlaceType; 

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

    double mLatitude=0; 
    double mLongitude=0; 

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

     mPlaceType = getResources().getStringArray(R.array.place_type); 
     mPlaceTypeName = getResources().getStringArray(R.array.place_type_name); 
     ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, mPlaceTypeName); 
     mSprPlaceType = (Spinner) findViewById(R.id.spr_place_type); 
     mSprPlaceType.setAdapter(adapter); 

     Button btnFind; 
     btnFind = (Button) findViewById(R.id.btn_find); 
     MapFragment fm=(MapFragment) getFragmentManager().findFragmentById(R.id.map); 
     map=fm.getMap(); 
     map.setMyLocationEnabled(true); 
      LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE); 
      Criteria criteria = new Criteria(); 
      String provider = locationManager.getBestProvider(criteria, true); 
      Location location = locationManager.getLastKnownLocation(provider); 
      if(location!=null) 
       onLocationChanged(location); 
      locationManager.requestLocationUpdates(provider, 20000, 0, this); 
      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=YOUR_API_KEY"); 
        PlacesTask placesTask = new PlacesTask(); 
        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); 
      urlConnection = (HttpURLConnection) url.openConnection(); 
      urlConnection.connect(); 
      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; 
    } 
    private class PlacesTask extends AsyncTask<String, Integer, String>{ 
     String data = null; 
     @Override 
     protected String doInBackground(String... url) { 
      try{ 
       data = downloadUrl(url[0]); 
      }catch(Exception e){ 
       Log.d("Background Task",e.toString()); 
      } 
      return data; 
     } 
     @Override 
     protected void onPostExecute(String result){ 
      ParserTask parserTask = new ParserTask(); 
      parserTask.execute(result); 
     } 
    } 

    private class ParserTask extends AsyncTask<String, Integer, List<HashMap<String,String>>>{ 
     JSONObject jObject; 
     @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]); 
       places = placeJsonParser.parse(jObject); 
      }catch(Exception e){ 
       Log.d("Exception",e.toString()); 
      } 
      return places; 
     } 
     @Override 
     protected void onPostExecute(List<HashMap<String,String>> list){ 
      mGoogleMap.clear(); 

      for(int i=0;i<list.size();i++){ 
       MarkerOptions markerOptions = new MarkerOptions(); 
       HashMap<String, String> hmPlace = list.get(i); 
       double lat = Double.parseDouble(hmPlace.get("lat")); 
       double lng = Double.parseDouble(hmPlace.get("lng")); 
       String name = hmPlace.get("place_name"); 
       String vicinity = hmPlace.get("vicinity"); 
       LatLng latLng = new LatLng(lat, lng); 
       markerOptions.position(latLng); 
       markerOptions.title(name + " : " + vicinity); 
       mGoogleMap.addMarker(markerOptions); 
      } 
     } 
    } 

    @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)); 
    } 
} 

Manifest

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package="com.gas" 
    android:versionCode="1" 
    android:versionName="1.0" > 

    <uses-sdk 
     android:minSdkVersion="15" 
     android:targetSdkVersion="15" /> 

    <permission 
     android:name="com.gas.permission.MAPS_RECEIVE" 
     android:protectionLevel="signature" /> 

    <uses-feature 
     android:glEsVersion="0x00020000" 
     android:required="true" /> 
    <uses-permission android:name="com.gas.permission.MAPS_RECEIVE" /> 
    <uses-permission android:name="android.permission.INTERNET" /> 
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> 
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/> 
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> 
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" /> 
    <uses-permission android:name="android.permission.com.google.android.providers.gsf.permission.READ_GSERVICES" /> 
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /> 
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 

    <uses-feature 
     android:name="android.hardware.location" 
     android:required="false" /> 
    <uses-feature 
     android:name="android.hardware.location.network" 
     android:required="false" /> 
    <uses-feature android:name="android.hardware.location.gps" /> 
    <uses-feature 
     android:name="android.hardware.wifi" 
     android:required="false" /> 

    <application 
     android:allowBackup="true" 
     android:icon="@drawable/ic_launcher" 
     android:label="@string/app_name" 
     android:theme="@style/AppTheme" > 
     <activity 
      android:name="com.gas.MainActivity" 
      android:label="@string/app_name" > 
      <intent-filter> 
       <action android:name="android.intent.action.MAIN" /> 

       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity> 

     <meta-data 
      android:name="com.google.android.maps.v2.API_KEY" 
      android:value="AIzaSyAtg_enu6Ox2l-WMyT-rpk_dUytQvSZaEw" /> 


    </application> 
</manifest> 

PlaceJasonParser

package com.gas; 

import java.util.ArrayList; 
import java.util.HashMap; 
import java.util.List; 

import org.json.JSONArray; 
import org.json.JSONException; 
import org.json.JSONObject; 

public class PlaceJSONParser { 

    /** 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; 
    } 
} 

Layout

<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="wrap_content" 
     android:layout_height="60dp" 
     android:layout_alignParentTop="true" /> 

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

    <fragment 
     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.MapFragment" /> 

    <TextView 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:text="@string/hello_world" /> 

</RelativeLayout> 

LogCat

05-23 04:19:27.233: D/AbsListView(4213): Get MotionRecognitionManager 
05-23 04:19:27.573: D/AndroidRuntime(4213): Shutting down VM 
05-23 04:19:27.573: W/dalvikvm(4213): threadid=1: thread exiting with uncaught    exception (group=0x40c18a68) 
05-23 04:19:27.573: E/AndroidRuntime(4213): FATAL EXCEPTION: main 
05-23 04:19:27.573: E/AndroidRuntime(4213): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.gas/com.gas.MainActivity}: java.lang.NullPointerException 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1970) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1995) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.app.ActivityThread.access$600(ActivityThread.java:128) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1161) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.os.Handler.dispatchMessage(Handler.java:99) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.os.Looper.loop(Looper.java:137) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.app.ActivityThread.main(ActivityThread.java:4517) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at java.lang.reflect.Method.invokeNative(Native Method) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at java.lang.reflect.Method.invoke(Method.java:511) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:760) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at dalvik.system.NativeStart.main(Native Method) 
05-23 04:19:27.573: E/AndroidRuntime(4213): Caused by: java.lang.NullPointerException 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at com.gas.MainActivity.onLocationChanged(MainActivity.java:375) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at com.gas.MainActivity.onCreate(MainActivity.java:194) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.app.Activity.performCreate(Activity.java:4470) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1053) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1934) 
05-23 04:19:27.573: E/AndroidRuntime(4213):  ... 11 more 
05-23 04:21:46.973: D/AbsListView(4760): Get MotionRecognitionManager 
05-23 04:21:47.253: D/AndroidRuntime(4760): Shutting down VM 
05-23 04:21:47.253: W/dalvikvm(4760): threadid=1: thread exiting with uncaught exception (group=0x40c18a68) 
05-23 04:21:47.253: E/AndroidRuntime(4760): FATAL EXCEPTION: main 
05-23 04:21:47.253: E/AndroidRuntime(4760): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.gas/com.gas.MainActivity}: java.lang.NullPointerException 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1970) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1995) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.app.ActivityThread.access$600(ActivityThread.java:128) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1161) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.os.Handler.dispatchMessage(Handler.java:99) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.os.Looper.loop(Looper.java:137) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.app.ActivityThread.main(ActivityThread.java:4517) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at java.lang.reflect.Method.invokeNative(Native Method) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at java.lang.reflect.Method.invoke(Method.java:511) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:760) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at dalvik.system.NativeStart.main(Native Method) 
05-23 04:21:47.253: E/AndroidRuntime(4760): Caused by: java.lang.NullPointerException 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at com.gas.MainActivity.onLocationChanged(MainActivity.java:375) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at com.gas.MainActivity.onCreate(MainActivity.java:194) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.app.Activity.performCreate(Activity.java:4470) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1053) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1934) 
05-23 04:21:47.253: E/AndroidRuntime(4760):  ... 11 more 

Answer 1

Вы прокомментировали

mGoogleMap = fragment.getMap(); 

Ваш mGoogleMap является недействительным в методе onLocationChanged при попытке перемещения камеры -> Линия 375 в MainActivity:

mGoogleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 

Answer 2

Вы используете GoogleMap map вместо GoogleMap mGoogleMap, так что вы должны использовать это:

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

вместо

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

потому что mGoogleMap является null ..