Android谷歌地图不在片段中工作

我正在使用带有viewpager的选项卡片段中的映射，但映射在我的应用程序中显示空指针异常

我添加了权限

和API密钥是否正确

<meta-data
            android:name="com.google.android.geo.API_KEY"
            android:value="@string/google_maps_key" />

我的日志：

1-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime: FATAL EXCEPTION: main
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime: Process: com.example.rubin, PID: 5673
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.maps.SupportMapFragment.getMapAsync(com.google.android.gms.maps.OnMapReadyCallback)' on a null object reference
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at com.example.rubin.HomeTabFragment2.onCreateView(HomeTabFragment2.java:34)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.app.Fragment.performCreateView(Fragment.java:1965)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1078)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1259)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:738)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1624)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:570)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:163)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.view.ViewPager.populate(ViewPager.java:1106)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.view.ViewPager.populate(ViewPager.java:952)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1474)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:727)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:463)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:727)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:463)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:727)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:463)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5535)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.design.widget.CoordinatorLayout.onMeasureChild(CoordinatorLayout.java:610)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.design.widget.CoordinatorLayout.onMeasure(CoordinatorLayout.java:677)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v4.widget.DrawerLayout.onMeasure(DrawerLayout.java:940)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5535)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.FrameLayout.onMeasure(FrameLayout.java:436)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.support.v7.internal.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:135)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5535)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5535)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.FrameLayout.onMeasure(FrameLayout.java:436)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5535)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1436)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.LinearLayout.measureVertical(LinearLayout.java:722)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.LinearLayout.onMeasure(LinearLayout.java:613)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5535)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.widget.FrameLayout.onMeasure(FrameLayout.java:436)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2615)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.View.measure(View.java:17547)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2015)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1173)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1379)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1061)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:     at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5885)
11-01 23:58:24.139 5673-5673/com.example.rubin E/AndroidRuntime:    at android.view.Choreogra

当我将片段更改为片段活动时，它工作得非常好。

---

但我无法弄清楚它将如何在片段中工作。请帮帮我

尝试更改以下行：

 SupportMapFragment mapFragment = (SupportMapFragment) getFragmentManager()
            .findFragmentById(R.id.map);

致：

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你的logcat投掷

AndroidRuntime:java.lang.NullPointerException:尝试调用 虚拟方法的无效性 com.google.android.gms.maps.SupportMapFragment.getMapAsync（com.google.android.gms.maps.OnMapReadyCallback）' 关于空对象引用

您可以尝试使用

getSupportFragmentManager

或

getChildFragmentManager

SupportMapFragment m = ((SupportMapFragment)
        .getSupportFragmentManager().findFragmentById(R.id.map));

或（完美解决方案）

公共最终碎片管理器getChildFragmentManager（）

在API级别17中添加了一个专用FragmentManager，用于放置和 管理此片段内部的片段

有关更多详细信息，请查看

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查看这些答案，它们与您的问题类似：您确定

R.layout.home\u tab\u fragment\u 1

此布局适用于您的

类hometab fragment2

？是的。我敢肯定。当我将片段更改为FragmentActivity时，它可以正常工作。不工作，无法解析方法getFragmentManager（），请尝试使用getSupportFragmentManager（）；非常感谢你。getChildFragmentManager（）为我工作。@Rubinellikunnathu很高兴听到这个消息。前进

SupportMapFragment mapFragment = (SupportMapFragment)v.getFragmentManager()
            .findFragmentById(R.id.map);

SupportMapFragment m = ((SupportMapFragment)
        .getSupportFragmentManager().findFragmentById(R.id.map));

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