Google Maps zurückkehren Null-Zeiger Ausnahme

Question

wenn ich versuche, die Karten auf meinem Fragment zu zeigen, es Null-Zeiger Ausnahme zurückkehrt. Ich habe alles auf das Manifest hinzugefügt jede und jede Berechtigung. Ich füge das Fragment seine XML-Datei und das Protokoll Katze

Chatffragment.java

public class ChatFragment extends Fragment{ 
     // Google Map 
     private GoogleMap googleMap; 

     public ChatFragment() { 
      // Required empty public constructor 
     } 

     @Override 
     public void onCreate(Bundle savedInstanceState) { 

      super.onCreate(savedInstanceState); 
     } 

     @Override 
     public View onCreateView(LayoutInflater inflater, ViewGroup container, 
           Bundle savedInstanceState) 
     { 

      View chatfrag = inflater.inflate(R.layout.chatfragment, container, false); 


      try { 
       // Loading map 
       initilizeMap(); 

      } catch (Exception e) { 
       e.printStackTrace(); 
      } 
      return chatfrag; 
     } 
      /** 
      * function to load map. If map is not created it will create it for you 
      * */ 

     private void initilizeMap() 
     { 
      if (googleMap == null) { 
       SupportMapFragment mapFrag = (SupportMapFragment) getActivity().getSupportFragmentManager().findFragmentById(R.id.map); 

       googleMap = mapFrag.getMap(); 
       googleMap.setMyLocationEnabled(true); 

       // check if map is created successfully or not 
       if (googleMap == null) { 
        Toast.makeText(getActivity(), 
          "Sorry! unable to create maps", Toast.LENGTH_SHORT) 
          .show(); 
       } 
      } 
     } 

     @Override 
     public void onResume() { 
      super.onResume(); 
      initilizeMap(); 


     } 




    } 

Die XML-Datei

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

    <fragment 
     android:id="@+id/map" 
     android:name="com.google.android.gms.maps.SupportMapFragment" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent"/> 

</RelativeLayout> 

Logcat

04-05 09:12:22.075 26987-26987/com.example.vikrant.safeshelter E/AndroidRuntime: FATAL EXCEPTION: main 
                       Process: com.example.vikrant.safeshelter, PID: 26987 


java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.android.gms.maps.GoogleMap com.google.android.gms.maps.SupportMapFragment.getMap()' on a null object reference 
                       at com.example.vikrant.safeshelter.ChatFragment.initilizeMap(ChatFragment.java:55) 
                       at com.example.vikrant.safeshelter.ChatFragment.onResume(ChatFragment.java:70) 
                       at android.support.v4.app.Fragment.performResume(Fragment.java:2020) 
                       at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1107) 
                       at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1252) 
                       at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:738) 
                       at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1617) 
                       at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:570) 
                       at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:164) 
                       at android.support.v4.view.ViewPager.populate(ViewPager.java:1177) 
                       at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:608) 
                       at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:570) 
                       at android.support.v4.view.ViewPager.setCurrentItem(ViewPager.java:551) 
                       at android.support.design.widget.TabLayout$ViewPagerOnTabSelectedListener.onTabSelected(TabLayout.java:1627) 
                       at android.support.design.widget.TabLayout.selectTab(TabLayout.java:837) 
                       at android.support.design.widget.TabLayout.selectTab(TabLayout.java:809) 
                       at android.support.design.widget.TabLayout$Tab.select(TabLayout.java:1077) 
                       at android.support.design.widget.TabLayout$1.onClick(TabLayout.java:643) 
                       at android.view.View.performClick(View.java:4759) 
                       at android.view.View$PerformClick.run(View.java:19770) 
                       at android.os.Handler.handleCallback(Handler.java:739) 
                       at android.os.Handler.dispatchMessage(Handler.java:95) 
                       at android.os.Looper.loop(Looper.java:135) 
                       at android.app.ActivityThread.main(ActivityThread.java:5234) 
                       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:909) 
                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:704) 

Linie 55 und 70 googleMap = mapFrag.getMap(); initialisierenMap();

Answer 1

Sie müssen warten, bis Karte immer geladen ....

public class ChatFragment extends Fragment implements OnMapReadyCallback { 

    private void initilizeMap() { 
     //SupportMapFragment mapFragment = (SupportMapFragment) fragmentManager.findFragmentById(R.id.map); 

     SupportMapFragment mapFrag = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map); 
     mapFrag.getMapAsync(this); 
    } 

    @Override 
    public void onMapReady(final GoogleMap map) { 
     googleMap = map; 
     //Do other stuff.......... 
    } 

} 

bearbeiten

SupportMapFragment mapFrag = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map); 

den Bearbeitungscode prüfen, verwenden ChildFragmentManager.

Answer 2

Ersetzen Sie diesen Code

SupportMapFragment mapFrag = (SupportMapFragment) getActivity().getSupportFragmentManager().findFragmentById(R.id.map); 
googleMap = mapFrag.getMap(); 

mit

googleMap = ((SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map)).getMap(); 

Check it!

Answer 3

java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.android.gms.maps.GoogleMap com.google.android.gms.maps.SupportMapFragment.getMap()' on a null object reference 

1. können Sie getChildFragmentManager() anstelle von getActivity().getSupportFragmentManager()
2. entfernen initilizeMap(); von Ihrer onResume Methode.

Referenz

SupportMapFragment.getMap() on a null object reference