Android Mapview标记延迟

Question

在我的带有导航抽屉的android应用中，我遇到了一个片段问题，其中使用了mapview：当我第一次启动该片段时，它仅显示我要标记的一个列表中的第一个画。我必须重新加载片段以查看地图上所有标记的绘制（例如，单击菜单上的另一个声音，然后再次单击地图片段）。我感觉该片段会在绘制所有标记之前启动地图。可能是问题吗？我该如何解决？这是我的代码：

public class MapFragment extends Fragment implements OnMapReadyCallback, GoogleMap.OnInfoWindowClickListener {

    private GoogleMap mGoogleMap;
    private MapView mMapView;
    private View mView;

    public MapFragment() {
        // Required empty public constructor
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setHasOptionsMenu(true);
        mView = inflater.inflate(R.layout.map_fragment, container, false);
        return mView;

    }

    @Override
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        mMapView = mView.findViewById(R.id.map);
        if (mMapView != null) {
            mMapView.onCreate(null);
            mMapView.onResume();
            mMapView.getMapAsync(this);

        }
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {

        mGoogleMap = googleMap;
        drawMarkerOnTheMap(mGoogleMap);
        mGoogleMap.getUiSettings().setZoomControlsEnabled(true);
        mGoogleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
        LatLng city = new LatLng(40.679425, 14.755968);
        CameraPosition camera = CameraPosition.builder().target(city).zoom(15).build();
        mGoogleMap.moveCamera(CameraUpdateFactory.newCameraPosition(camera));
    }

    private void drawMarkerOnTheMap(GoogleMap googleMap) {
        try {
            InputStream is = getContext().getAssets().open("turisticpoint.xml");
            DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
            Document doc = dBuilder.parse(is);
            Element element=doc.getDocumentElement();
            element.normalize();
            NodeList nList = doc.getElementsByTagName("turisticpoint");
            for (int i=0; i<nList.getLength(); i++) {

                Node node = nList.item(i);
                if (node.getNodeType() == Node.ELEMENT_NODE) {

                    Element element2 = (Element) node;

                    String title = getValue("title", element2);
                    String tit = getContext().getResources().getString(getContext().getResources().getIdentifier(title, "string", getActivity().getPackageName()));

                    Double latitude = Double.valueOf(getValue("latitude", element2));
                    Double longitude= Double.valueOf(getValue("longitude", element2));
                    LatLng position = new LatLng(latitude, longitude);
                    MarkerOptions marker = new MarkerOptions().
                        position(position).
                        title(tit)
                        .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_ORANGE));
                    googleMap.addMarker(marker);

                }
            }
        } catch (Exception e) {e.printStackTrace();}
    }

    private static String getValue(String tag, Element element) {
            NodeList nodeList = element.getElementsByTagName(tag).item(0).getChildNodes();
            Node node = nodeList.item(0);
            return node.getNodeValue();
    }
}

在我的logcat中，我刚发现此错误：

E/libprocessgroup: failed to make and chown /acct/uid_10063: Read-only file system

这是我的清单文件：

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="package">

    <supports-screens
        android:anyDensity="true"
        android:largeScreens="true"
        android:normalScreens="true"
        android:smallScreens="true"
        android:xlargeScreens="true" />

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


    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity
            android:name=".HomeActivity"
            android:label="@string/app_name"
            android:theme="@style/AppTheme.NoActionBar">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

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

        <activity
            android:name=".MainActivity"
            android:label="MyApp"
            android:theme="@style/AppTheme.NoActionBar"></activity>

    </application>
</manifest>

和我的build.gradle：

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "myappId"
        minSdkVersion 15
        targetSdkVersion 28
        multiDexEnabled true
        versionCode 16
        versionName "1.5"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        missingDimensionStrategy 'minApi', 'minApi18', 'minApi23'
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support:support-v4:28.0.0'
    implementation 'com.android.support:design:28.0.0'
    implementation 'com.google.android.gms:play-services-maps:16.1.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
}

这是一个类似于我的xml文件：

<records>
    <turisticpoint>
        <titolo>Gardens</titolo>
        <latitudine>40.678480</latitudine>
        <longitudine>14.753152</longitudine>
    </turisticpoint>

    <turisticpoint>
        <titolo>Castle</titolo>
        <latitudine>40.6794731</latitudine>
        <longitudine>14.7544442</longitudine>
    </turisticpoint>

    <turisticpoint>
        <titolo>Beach</titolo>
        <latitudine>40.6965378</latitudine>
        <longitudine>14.7777038</longitudine>
    </turisticpoint>
</records>

我总共有13个旅游点。