AndroidでGoogleマップのcom.google.android.gms.maps.model.Marker com.google.android.gms.maps.GoogleMap.addMarkerを修正するには

Question

私のアプリケーションでGoogleMapを使用します。 for create GoogleMap私はこのパッチを使用します：New - > Google - > Google Map Activity、以下のコードを書いていますが、show me Force強制終了エラーを実行しています。
MapActivityコード：

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback { 

    private GoogleMap mMap; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_maps); 
     // Obtain the SupportMapFragment and get notified when the map is ready to be used. 
     SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager() 
       .findFragmentById(R.id.map); 
     mapFragment.getMapAsync(this); 

     setUpMap(); 
    } 


    /** 
    * Manipulates the map once available. 
    * This callback is triggered when the map is ready to be used. 
    * This is where we can add markers or lines, add listeners or move the camera. In this case, 
    * we just add a marker near Sydney, Australia. 
    * If Google Play services is not installed on the device, the user will be prompted to install 
    * it inside the SupportMapFragment. This method will only be triggered once the user has 
    * installed Google Play services and returned to the app. 
    */ 
    @Override 
    public void onMapReady(GoogleMap googleMap) { 
     mMap = googleMap; 

     // Add a marker in Sydney and move the camera 
     LatLng sydney = new LatLng(-34, 151); 
     mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney")); 
     mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney)); 
    } 

    private void setUpMap() { 
     mMap.addMarker(new MarkerOptions().position(new LatLng(0, 0)).title("Marker").snippet("Snippet")); 

     // Enable MyLocation Layer of Google Map 
     if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { 
      // TODO: Consider calling 
      // ActivityCompat#requestPermissions 
      // here to request the missing permissions, and then overriding 
      // public void onRequestPermissionsResult(int requestCode, String[] permissions, 
      //           int[] grantResults) 
      // to handle the case where the user grants the permission. See the documentation 
      // for ActivityCompat#requestPermissions for more details. 
      return; 
     } 
     mMap.setMyLocationEnabled(true); 

     // Get LocationManager object from System Service LOCATION_SERVICE 
     LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 

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

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

     // Get Current Location 
     Location myLocation = locationManager.getLastKnownLocation(provider); 

     // set map type 
     mMap.setMapType(GoogleMap.MAP_TYPE_NORMAL); 

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

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

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

     // Show the current location in Google Map 
     mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 

     // Zoom in the Google Map 
     mMap.animateCamera(CameraUpdateFactory.zoomTo(14)); 
     mMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("You are here!").snippet("Consider yourself located")); 
    } 
} 

XMLコード：

<fragment xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:map="http://schemas.android.com/apk/res-auto" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:id="@+id/map" 
    android:name="com.google.android.gms.maps.SupportMapFragment" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    tools:context="com.tellfa.googlepluslogin.map.MapsActivity" /> 

LogCatエラー：

05-21 17:34:45.173 31057-31057/com.tellfa.googlepluslogin E/AndroidRuntime: FATAL EXCEPTION: main 
                      Process: com.tellfa.googlepluslogin, PID: 31057 
                      java.lang.RuntimeException: Unable to start activity ComponentInfo{com.tellfa.googlepluslogin/com.tellfa.googlepluslogin.map.MapsActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.android.gms.maps.model.Marker com.google.android.gms.maps.GoogleMap.addMarker(com.google.android.gms.maps.model.MarkerOptions)' on a null object reference 
                       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2331) 
                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2391) 
                       at android.app.ActivityThread.access$800(ActivityThread.java:151) 
                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1309) 
                       at android.os.Handler.dispatchMessage(Handler.java:102) 
                       at android.os.Looper.loop(Looper.java:135) 
                       at android.app.ActivityThread.main(ActivityThread.java:5349) 
                       at java.lang.reflect.Method.invoke(Native Method) 
                       at java.lang.reflect.Method.invoke(Method.java:372) 
                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908) 
                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703) 
                      Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.android.gms.maps.model.Marker com.google.android.gms.maps.GoogleMap.addMarker(com.google.android.gms.maps.model.MarkerOptions)' on a null object reference 
                       at com.tellfa.googlepluslogin.map.MapsActivity.setUpMap(MapsActivity.java:58) 
                       at com.tellfa.googlepluslogin.map.MapsActivity.onCreate(MapsActivity.java:34) 
                       at android.app.Activity.performCreate(Activity.java:6020) 
                       at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105) 
                       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2284) 
                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2391)  
                       at android.app.ActivityThread.access$800(ActivityThread.java:151)  
                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1309)  
                       at android.os.Handler.dispatchMessage(Handler.java:102)  
                       at android.os.Looper.loop(Looper.java:135)  
                       at android.app.ActivityThread.main(ActivityThread.java:5349)  
                       at java.lang.reflect.Method.invoke(Native Method)  
                       at java.lang.reflect.Method.invoke(Method.java:372)  
                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908)  
                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703)  
05-21 17:34:47.180 31057-31255/com.tellfa.googlepluslogin E/DynamiteModule: Failed to load module descriptor class: Didn't find class "com.google.android.gms.dynamite.descriptors.com.google.android.gms.googlecertificates.ModuleDescriptor" on path: DexPathList[[zip file "/data/app/com.tellfa.googlepluslogin-1/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]] 

どのように私はこの問題を解決することができますか？

Answer 1

私は現在使用しているスニペットに従ってください。

public class MyActivity extends FragmentActivity implements LocationListener { 

    GoogleMap googleMap; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     //show error dialog if GoolglePlayServices not available 
     if (!isGooglePlayServicesAvailable()) { 
      finish(); 
     } 
     setContentView(R.layout.activity_my); 
     SupportMapFragment supportMapFragment = 
       (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.googleMap); 
     googleMap = supportMapFragment.getMap(); 
     googleMap.setMyLocationEnabled(true); 
     LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE); 
     Criteria criteria = new Criteria(); 
     String bestProvider = locationManager.getBestProvider(criteria, true); 
     Location location = locationManager.getLastKnownLocation(bestProvider); 
     if (location != null) { 
      onLocationChanged(location); 
     } 
     locationManager.requestLocationUpdates(bestProvider, 20000, 0, this); 
    } 

    @Override 
    public void onLocationChanged(Location location) { 
     TextView locationTv = (TextView) findViewById(R.id.latlongLocation); 
     double latitude = location.getLatitude(); 
     double longitude = location.getLongitude(); 
     LatLng latLng = new LatLng(latitude, longitude); 
     googleMap.addMarker(new MarkerOptions().position(latLng)); 
     googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 
     googleMap.animateCamera(CameraUpdateFactory.zoomTo(15)); 
     locationTv.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 
    } 

    private boolean isGooglePlayServicesAvailable() { 
     int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this); 
     if (ConnectionResult.SUCCESS == status) { 
      return true; 
     } else { 
      GooglePlayServicesUtil.getErrorDialog(status, this, 0).show(); 
      return false; 
     } 
    } 
} 

XML

<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"> 

    <fragment 
     android:id="@+id/googleMap" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     class="com.google.android.gms.maps.SupportMapFragment" 
     android:layout_above="@+id/latlongLocation" /> 

    <TextView 
     android:id="@+id/latlongLocation" 
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content" 
     android:gravity="bottom" 
     android:layout_alignParentBottom="true" 
     android:background="#ff058fff" 
     android:paddingTop="5dp" 
     android:paddingBottom="5dp" 
     android:textColor="#ffffffff" 
     android:paddingLeft="5dp" 
     android:paddingRight="5dp" /> 
</RelativeLayout> 

必要Manifestでアクセス許可があります。

<uses-permission android:name="com.javapapers.currentlocationinmap.permission.MAPS_RECEIVE" /> 
    <uses-permission android:name="android.permission.INTERNET" /> 
    <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.ACCESS_COARSE_LOCATION" /> 
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> 

注：ランタイム許可だけでなく、あなたがOPで使用しているを適用します。

Answer 2

mMapはsetUpMap()をonCreate()から呼び出していますが、現時点ではまだマップが初期化されていないためnullです。 onMapReady()メソッドで初期化されます。

setUpMap()に電話をかけてonMapReady()に移動してください。

Answer 3

私はそれについて多くの知識を持っていないが、私はあなたのエラーは、この行であることを考える：

mMap.addMarker(new MarkerOptions().position(new LatLng(0,  0)).title("Marker").snippet("Snippet")); 

MMAPは、あなたがsetUpMapを（呼び出してみてください、それにマーカーを追加することができます最初に初期化する必要があります） onMapReady（）内にあります。