Java Fragment中的android MapView

android MapView in Fragment

提问by user3833308

I want to have MapViewinside my Fragment

我想MapView在我的里面Fragment

This is my FragmentLayoutxml file

这是我的FragmentLayoutxml 文件

<?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"
    android:background="#17df0d"
    android:orientation="vertical" >

<com.google.android.gms.maps.MapView
    android:id="@+id/mapview"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_above="@+id/textView1"
    android:layout_alignParentLeft="true"
    android:layout_alignParentRight="true"
    android:layout_marginBottom="70dp" >

</com.google.android.gms.maps.MapView>
</RelativeLayout>

My AndroidManifest.xmlfile

我的AndroidManifest.xml档案

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="a.b.c.d"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="11"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >

        <meta-data
            android:name="com.google.android.maps.v2.API_KEY"
            android:value="your_api_key" />
        <meta-data
            android:name="com.google.android.gms.version"
            android:value="@integer/google_play_services_version" />


    </application>

    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

    <permission
        android:name="a.b.c.d.permission.MAPS_RECEIVE"
        android:protectionLevel="signature" />

    <uses-permission android:name="a.b.c.d.permission.MAPS_RECEIVE" />

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

</manifest>

and my Fragment class

和我的片段类

public class ReportFragment extends Fragment implements LocationListener {
    MapView mapView = null; //eventually it is being read from view and assigned

when I launch the app, I do not see any map view in my Fragment

当我启动应用程序时，我在 Fragment 中看不到任何地图视图

采纳答案by M D

From Josh Holtz's example on GitHub:

来自GitHub 上 Josh Holtz 的示例：

You should add MapViewin your Layoutlike

你应该添加MapView你Layout喜欢的

 <com.google.android.gms.maps.MapView 
    android:id="@+id/mapview"
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" />

and implement your Fragmentlike

并实施你Fragment喜欢的

public class SomeFragment extends Fragment {

MapView mapView;
GoogleMap map;

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

    // Gets the MapView from the XML layout and creates it
    mapView = (MapView) v.findViewById(R.id.mapview);
    mapView.onCreate(savedInstanceState);

    // Gets to GoogleMap from the MapView and does initialization stuff
    map = mapView.getMap();
    map.getUiSettings().setMyLocationButtonEnabled(false);
    map.setMyLocationEnabled(true);

    // Needs to call MapsInitializer before doing any CameraUpdateFactory calls
    try {
        MapsInitializer.initialize(this.getActivity());
    } catch (GooglePlayServicesNotAvailableException e) {
        e.printStackTrace();
    }

    // Updates the location and zoom of the MapView
    CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(new LatLng(43.1, -87.9), 10);
    map.animateCamera(cameraUpdate);

    return v;
}

@Override
public void onResume() {
    mapView.onResume();
    super.onResume();
}

@Override
public void onDestroy() {
    super.onDestroy();
    mapView.onDestroy();
 }

 @Override
 public void onLowMemory() {
    super.onLowMemory();
    mapView.onLowMemory();
  }

}

回答by Florin

Adding to M D's answer:

添加到 MD 的答案：

From documentation:

从文档：

A GoogleMap must be acquired using getMapAsync(OnMapReadyCallback). The MapView automatically initializes the maps system and the view.

必须使用 getMapAsync(OnMapReadyCallback) 获取 GoogleMap。MapView 自动初始化地图系统和视图。

According to this, the more correct way to initialize GoogleMapis using getMapAsync.

据此，更正确的初始化方法GoogleMap是使用getMapAsync.

Note that your class has to implement OnMapReadyCallback

请注意，您的课程必须实现 OnMapReadyCallback

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

    mMapView = (MapView) v.findViewById(R.id.map_view);
    mMapView.onCreate(savedInstanceState);
    mMapView.getMapAsync(this); //this is important

    return v;
}

@Override
public void onMapReady(GoogleMap googleMap) {
    mGoogleMap = googleMap;
    mGoogleMap.getUiSettings().setZoomControlsEnabled(true);
    mGoogleMap.addMarker(new MarkerOptions().position(/*some location*/));
    mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(/*some location*/, 10));
}

@Override
public void onResume() {
    super.onResume();
    mMapView.onResume();
}

@Override
public void onPause() {
    super.onPause();
    mMapView.onPause();
}

@Override
public void onDestroy() {
    super.onDestroy();
    mMapView.onDestroy();
}

@Override
public void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    mMapView.onSaveInstanceState(outState);
}

@Override
public void onLowMemory() {
    super.onLowMemory();
    mMapView.onLowMemory();
}

回答by lomza

In case somebody is looking for a Kotlin version of MapView Fragment ;)

如果有人正在寻找 Kotlin 版本的 MapView Fragment ;)

class MapViewKotlinFragment : Fragment(), OnMapReadyCallback {

private var mMap: MapView? = null

override fun onSaveInstanceState(outState: Bundle?) {
    super.onSaveInstanceState(outState)

    mMap?.onSaveInstanceState(outState)
}

override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, savedInstanceState: Bundle?): View? {
    val view = inflater?.inflate(R.layout.fragment_map, container, false)

    mMap = view?.findViewById(R.id.mapViewPlaces) as MapView
    mMap?.onCreate(savedInstanceState)
    mMap?.getMapAsync(this)

    return view
}

override fun onResume() {
    super.onResume()
    mMap?.onResume()
}

override fun onPause() {
    super.onPause()
    mMap?.onPause()
}

override fun onStart() {
    super.onStart()
    mMap?.onStart()
}

override fun onStop() {
    super.onStop()
    mMap?.onStop()
}

override fun onDestroy() {
    super.onDestroy()
    mMap?.onDestroy()
}

override fun onLowMemory() {
    super.onLowMemory()
    mMap?.onLowMemory()
}

override fun onMapReady(googleMap: GoogleMap) {
    googleMap.addMarker(MarkerOptions().position(LatLng(0.0, 0.0)).title("Marker"))
}

回答by ComeIn

Makes sure you are overriding or calling OnDestroyViewas well as OnDestroy. Something like ...

确保您正在覆盖或调用 OnDestroy View以及 OnDestroy。就像是 ...

    public override void OnDestroy()
    {            
        base.OnDestroy();
        MapView.OnDestroy();
        OnDestroyView();            
    }

    public override void OnDestroyView()
    {            
        base.OnDestroyView();
        mapReadyCallbackList.Clear();            
}