Google Maps Android API v2显示空白地图

我正在尝试实现一个简单的地图，并且已经在清单文件中添加了所有用户权限并启用了Google API V2，但仍仅显示空白地图。

list_doctor.xml

<?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:orientation="vertical"
    android:padding="10dp" >



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

list_doctor.java

public class listDoctor extends Activity implements OnMapReadyCallback{
    private MapFragment fragment;
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.listdoctor);
        try {
            // Loading map
            initilizeMap();

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

    }

    /**
     * function to load map. If map is not created it will create it for you
     */
    private void initilizeMap() {
        if (fragment == null) {
            fragment = ((MapFragment) getFragmentManager().findFragmentById(R.id.map));
            fragment.getMapAsync(this);
            // check if map is created successfully or not
            if (fragment == null) {
                Toast.makeText(getApplicationContext(),
                        "Sorry! unable to create maps", Toast.LENGTH_SHORT)
                        .show();
            }
        }
    }

    @Override
    protected void onResume() {
        super.onResume();
        initilizeMap();
    }

    @Override
       public void onMapReady(GoogleMap map) {
        LatLng sydney = new LatLng(-33.867, 151.206);

        map.setMyLocationEnabled(true);
        map.moveCamera(CameraUpdateFactory.newLatLngZoom(sydney, 13));

        map.addMarker(new MarkerOptions()
                .title("Sydney")
                .snippet("The most populous city in Australia.")
                .position(sydney));
    }

}

Manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.winthrop"
    android:versionCode="1"
    android:versionName="1.0" >
    <permission
        android:name="com.winthrop.permission.MAPS_RECEIVE"
        android:protectionLevel="signature" />

    <uses-permission android:name="com.winthrop.permission.MAPS_RECEIVE" />

    <uses-sdk
        android:minSdkVersion="12"
        android:targetSdkVersion="17" />

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <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.WRITE_EXTERNAL_STORAGE" />

    <!-- Required to show current location -->
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

    <!-- Required OpenGL ES 2.0. for Maps V2 -->
    <uses-feature
        android:glEsVersion="0x00020000"
        android:required="true" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name">
        <activity
            android:name="com.winthrop.MainActivity"
            android:label="@string/app_name"
            android:theme="@style/AppBaseTheme">
        </activity>

              <!-- Goolge API Key -->
        <meta-data
            android:name="com.google.android.gms.version"
            android:value="@integer/google_play_services_version" />
        <meta-data
            android:name="com.google.android.maps.v2.API_KEY"
            android:value="692634518367-dgd8tgncr13tcvhpj5uuj9bmm66d52pq" />

    </application>

</manifest>

logcat错误

03-23 11:06:31.054: E/Google Maps Android API(15456): Authorization failure.  Please see https://developers.google.com/maps/documentation/android/start for how to correctly set up the map.