Android SupportMapFragment.getMap() 返回 null

Question

在我的以下代码中，getMap() 返回 null，这会停止应用程序。如果我不对 map 做任何事情(即删除最后两行)，它就会正确显示。知道为什么吗？谢谢。

public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        FragmentManager fragmentManager = getSupportFragmentManager();
        SupportMapFragment mapFragment = SupportMapFragment.newInstance();
        mapFragmentId = mapFragment.getId();
        FragmentTransaction transaction =  fragmentManager.beginTransaction();
        transaction.add(R.id.my_container, mapFragment);
        transaction.commit();

        mMap = mapFragment.getMap();
        mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
    }

Answer 1

副本:SupportMapFragment.getmap() returns null

Check your layout xml file. I noticed that I wasn't referencing: android:name="com.google.android.gms.maps.SupportMapFragment" but rather: android:name="com.google.android.gms.maps.MapFragment"

The name should be: android:name="com.google.android.gms.maps.SupportMapFragment"