Android 试图在片段活动中放置映射

在我的Android应用程序中，我在一个扩展片段的类中显示了一个Google地图

目前，仅显示地图，但我无法从SupportFragmentManager获取地图

我所做的是使Android Studio中的MapActivity适应我的应用程序

这是我的密码：

public class Tab2 extends Fragment {

    private GoogleMap mMap; // Might be null if Google Play services APK is not available.

    private double latitud_del_hotel, longitud_del_hotel;
    private String nombre_del_hotel;
    private GoogleMap map;

    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.tab_2, container, false);
        //setUpMapIfNeeded();
        return v;
    }

    @Override
    public void onActivityCreated(Bundle state) {
        super.onActivityCreated(state);
        setUpMapIfNeeded();


    }

    private void setUpMapIfNeeded() {
        // Do a null check to confirm that we have not already instantiated the map.
        if (mMap == null) {
            // Try to obtain the map from the SupportMapFragment.
            mMap = ((SupportMapFragment) getActivity().getSupportFragmentManager().findFragmentById(R.id.map))
                    .getMap();
            // Check if we were successful in obtaining the map.
            if (mMap != null) {
                setUpMap();
            }
        }
    }

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

}

我得到一个异常：java.lang.NullPointerException 请访问com.solinpromex.elpasojurezexperience.Tab2.setupmapifneed

我已尝试从两个方法调用方法

setupmapifneed（）

：onCreateView和onActivityCreated。这两种情况都会引发异常

如果删除

setupmapifneed（）

，则会显示贴图，但我想添加贴图对象

欢迎任何帮助

编辑

从logcat完成异常日志：

09-16 00:34:09.614  13999-13999/com.solinpromex.elpasojuarezexperience E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.solinpromex.elpasojuarezexperience, PID: 13999
    java.lang.NullPointerException
            at com.solinpromex.elpasojuarezexperience.Tab2.setUpMapIfNeeded(Tab2.java:66)
            at com.solinpromex.elpasojuarezexperience.Tab2.onActivityCreated(Tab2.java:57)
            at android.support.v4.app.Fragment.performActivityCreated(Fragment.java:1797)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:979)
            at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1138)
            at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:740)
            at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1501)
            at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:490)
            at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:163)
            at android.support.v4.view.ViewPager.populate(ViewPager.java:1105)
            at android.support.v4.view.ViewPager.populate(ViewPager.java:951)
            at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1473)
            at android.view.View.measure(View.java:16857)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5378)
            at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1621)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:742)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:607)
            at android.view.View.measure(View.java:16857)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5378)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:340)
            at android.support.v7.internal.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:124)
            at android.view.View.measure(View.java:16857)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5378)
            at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1621)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:742)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:607)
            at android.view.View.measure(View.java:16857)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5378)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:340)
            at android.view.View.measure(View.java:16857)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5378)
            at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1621)
            at android.widget.LinearLayout.measureVertical(LinearLayout.java:742)
            at android.widget.LinearLayout.onMeasure(LinearLayout.java:607)
            at android.view.View.measure(View.java:16857)
            at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5378)
            at android.widget.FrameLayout.onMeasure(FrameLayout.java:340)
            at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2332)
            at android.view.View.measure(View.java:16857)
            at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2271)
            at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1334)
            at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1532)
            at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1211)
            at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6282)
            at android.view.Choreographer$CallbackRecord.run(Choreographer.java:788)
            at android.view.Choreographer.doCallbacks(Choreographer.java:591)
            at android.view.Choreographer.doFrame(Choreographer.java:560)
            at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:774)
            at android.os.Handler.handleCallback(Handler.java:808)
            at android.os.Handler.dispatchMessage(Handler.java:103)
            at android.os.Looper.loop(Looper.java:193)
            at android.app.ActivityThread.main(ActivityThread.java:5299)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:515)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:825)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:641)
            at dalvik.system.NativeStart.main(Native Method)

编辑2

布局文件选项卡2

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

    <LinearLayout
        android:orientation="vertical"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent">

        <fragment xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:name="com.google.android.gms.maps.MapFragment"
            android:id="@+id/map"
            android:layout_alignParentTop="true"
            android:layout_alignParentBottom="true"
            android:layout_alignParentLeft="true"
            android:layout_alignParentRight="true" />
    </LinearLayout>
</RelativeLayout>

---

遵循此代码。希望这可能会有所帮助。根据您的要求进行必要的更改。我认为您正在将此地图视图作为一个片段添加到选项卡视图中

    public class DealsCloseBy extends Fragment {

    SupportMapFragment mMapView;
    private GoogleMap googleMap;


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // inflat and return the layout
        View v = inflater.inflate(R.layout.fragment_deals_close_by, container, false);
        mMapView = ((SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map));
        mMapView.onCreate(savedInstanceState);

        mMapView.onResume();// needed to get the map to display immediately

        try {
            MapsInitializer.initialize(getActivity().getApplicationContext());
        } catch (Exception e) {
            e.printStackTrace();
        }

        googleMap = mMapView.getMap();
        // latitude and longitude
        double latitude = 13.0294278;
        double longitude =80.24667829999999;

        // create marker
        MarkerOptions marker = new MarkerOptions().position(new LatLng(latitude, longitude)).title("Hello Maps").icon(BitmapDescriptorFactory.fromResource(R.mipmap.map_pin));

        // Changing marker icon
        // marker.icon(BitmapDescriptorFactory
        // .defaultMarker(BitmapDescriptorFactory.HUE_ROSE));

        // adding marker
        googleMap.addMarker(marker);
        CameraPosition cameraPosition = new CameraPosition.Builder()
                .target(new LatLng(13.0294278, 80.24667829999999)).zoom(12).build();
        googleMap.animateCamera(CameraUpdateFactory
                .newCameraPosition(cameraPosition));

        // Perform any camera updates here
        return v;
    }
}

在xml文件中，使用以下命令代替映射片段：-

    <fragment
    android:id="@+id/map"
    android:layout_width="fill_parent"
    android:layout_height="0dp"
    android:layout_weight="1"
    class="com.google.android.gms.maps.SupportMapFragment"/>

---

如果您使用最新的

GooglePlayServices

，您可以使用

getMapAsync

功能，该功能将自动初始化地图系统和视图

在布局中也使用

地图视图

这就是我在片段中添加地图的方式

public class MapFragment extends Fragment implements OnMapReadyCallback {

     @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
            view = inflater.inflate(R.layout.fragment_tab_fragment1, container, false);

            FragmentManager manager = getFragmentManager();
            FragmentTransaction transaction = manager.beginTransaction();
            SupportMapFragment fragment = new SupportMapFragment();
            transaction.add(R.id.mapView, fragment);
            transaction.commit();

            fragment.getMapAsync(this);

            return view;
        }

   @Override
   public void onMapReady(GoogleMap map) {
      //map is ready
      map.addMarker(...
 }
}

在xml中

---

你应该使用最新的谷歌地图API。在这里，他们已经提供了MapFragment类来显示地图@AkhileshKumar，谢谢你。我会看看你的建议。谢谢@Animesh，我在MapsInitializer收到一个警告…，无法解决它。@mvasco-什么样的警告？@mvasco-我想这里是你面临问题的地方：-mMapView=（（SupportMapFragment）getChildFragmentManager（）.findFragmentById（R.id.map））；代替R.id.map，放置您自己的xml mapview id，希望它能工作。我已经在使用它了，R.id.map是布局文件中包含地图的片段。@mvasco请查看我在这里发布的片段标记。代替map片段，您需要使用SupportMapFragment。类似这样的东西。希望它对你有用。如果你仍然没有得到它，请查看我的最新答案。谢谢你，老板……你让我开心了，，，它很有魅力。@mvasco很高兴我能帮上忙：）

<com.google.android.gms.maps.MapView
    android:id="@+id/mapView"
    class="com.google.android.gms.maps.SupportMapFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

compile 'com.google.android.gms:play-services:8.3.0'