Android-SupportMapFragment 显示空白地图

Question

我想显示 supportMapFragment 来填充我的主要活动，顺便说一下我在运行时请求位置权限并成功授予它。发生的情况是我得到一个空白的地图视图，没有别的。 我也给了 api 密钥，预计是正确的

这是我的主要活动代码：

    public class MainActivity extends AppCompatActivity {
    private static final int REQUEST_ID_MULTIPLE_PERMISSIONS = 1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        RequestPermissions requestPermissions = new RequestPermissions(this, this);
        requestPermissions.checkAndRequestPermissions();

        FragmentManager fmanager = getSupportFragmentManager();
        Fragment fragment = fmanager.findFragmentById(R.id.map);
        SupportMapFragment supportmapfragment = (SupportMapFragment)fragment;
        GoogleMap supportMap = supportmapfragment.getMap();
    }


    @Override
    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults) {
        switch (requestCode) {
            case REQUEST_ID_MULTIPLE_PERMISSIONS: {

                Map<String, Integer> perms = new HashMap<String, Integer>();
                // Initialize the map with both permissions
                perms.put(android.Manifest.permission.ACCESS_COARSE_LOCATION, PackageManager.PERMISSION_GRANTED);
                perms.put(android.Manifest.permission.ACCESS_FINE_LOCATION, PackageManager.PERMISSION_GRANTED);

                // Fill with actual results from user
                if (grantResults.length > 0) {
                    for (int i = 0; i < permissions.length; i++)
                        perms.put(permissions[i], grantResults[i]);
                }
            }
        }
    }
}

这是我的清单：

<?xml version="1.0" encoding="utf-8"?>

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="17" />
<uses-feature
    android:glEsVersion="0x00020000"
    android:required="true" />
<uses-feature android:name="android.hardware.location.gps"
    android:required="true"/>
<uses-feature android:name="android.hardware.location.network"
    android:required="true"/>
<uses-feature
    android:name="android.hardware.location"
    android:required="true" />

<permission
    android:name="com.truiton.supportmapfragment.permission.MAPS_RECEIVE"
    android:protectionLevel="signature" />
<uses-permission android:name="com.truiton.supportmapfragment.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" />

<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=".MainActivity">
        <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.maps.v2.API_KEY"
        android:value="@string/MapsKey" />
</application>

活动 xml：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.khairy.fm2apps.MainActivity" >

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

Answer 1

右键单击您的项目并浏览下面的图像；

Answer 2

在 onCreate() 方法中尝试以下代码

 @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    RequestPermissions requestPermissions = new RequestPermissions(this, this);
    requestPermissions.checkAndRequestPermissions();

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

Answer 3

确保您通过 API 和服务部分在 Google Cloud Platform 中为您的项目启用 Maps SDK for Android