android - 初始化谷歌地图时 mapFragment.getMapAsync(this) 出现空指针异常

Question

当我使用 v6.5.87 的 Google Play 服务时，调用 getMapAsync() 时出现空指针异常。我在我的 Fragment 的 xml 布局中使用了 SupportMapFragment。

我的代码:

SupportMapFragment mapFragment = (SupportMapFragment) getActivity()
        .getSupportFragmentManager().findFragmentById(R.id.mapFragment);

mapFragment.getMapAsync(this);

注意:在较旧的 Google Play 服务版本上调用 getMap() 没有问题，但 getMap() 现在已弃用 ( docs )。

这是 NPE 的堆栈跟踪:

java.lang.NullPointerException
            at com.decos.fixi.fragments.FragmentLocationMap.initializeMap(FragmentLocationMap.java:132)
            at com.decos.fixi.fragments.FragmentLocationMap.onCreateView(FragmentLocationMap.java:95)
            at android.support.v4.app.Fragment.performCreateView(Fragment.java:1786)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:947)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1126)
            at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:739)
            at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1489)
            at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:454)
            at android.os.Handler.handleCallback(Handler.java:615)
            at android.os.Handler.dispatchMessage(Handler.java:92)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:4921)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:511)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1027)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:794)
            at dalvik.system.NativeStart.main(Native Method)

Answer 1

终于找到答案了!

SupportMapFragment mapFragment = (SupportMapFragment) this.getChildFragmentManager()
                .findFragmentById(R.id.mapFragment);

代替

SupportMapFragment mapFragment = (SupportMapFragment) this.getSupportFragmentManager()
                .findFragmentById(R.id.mapFragment);

getChildFragmentManager() 成功了。