title: Google Map view shows only grey screen with zoom button
body: <p>I am Using android Google map API-2 for my application. When clicking map view it shows only a screen with zoom button.</p>
  
  <p>my AndroidManifest.xml file</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.burusoth.advertise"
  android:versionCode="1"
  android:versionName="1.0" &gt;
  
  &lt;permission
      android:name="com.burusoth.advertise.permission.MAPS_RECEIVE"
      android:protectionLevel="signature" /&gt;
  
  &lt;uses-permission android:name="com.burusoth.advertise.permission.MAPS_RECEIVE" /&gt;
  
  &lt;uses-permission android:name="android.permission.CALL_PHONE" &gt;
  &lt;/uses-permission&gt;
  &lt;uses-permission android:name="android.permission.INTERNET" &gt;
  &lt;/uses-permission&gt;
  &lt;uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /&gt;
  &lt;uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /&gt;
  &lt;uses-permission android:name="android.permission.INTERNET" /&gt;
  &lt;uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" /&gt;
  &lt;!-- Required to show current location --&gt;
  &lt;uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" /&gt;
  &lt;uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /&gt;
  
  &lt;uses-sdk
      android:minSdkVersion="11"
      android:targetSdkVersion="17" /&gt;
  
  &lt;!-- Required OpenGL ES 2.0. for Maps V2 --&gt;
  &lt;uses-feature
      android:glEsVersion="0x00020000"
      android:required="true" /&gt;
  
  &lt;application
      android:allowBackup="true"
      android:icon="@drawable/ic_launcher"
      android:label="@string/app_name"
      android:theme="@style/AppTheme" &gt;
      &lt;activity
          android:name="com.burusoth.advertise.MainActivity"
          android:label="@string/app_name" &gt;
          &lt;intent-filter&gt;
              &lt;action android:name="android.intent.action.MAIN" /&gt;
  
              &lt;category android:name="android.intent.category.LAUNCHER" /&gt;
          &lt;/intent-filter&gt;
      &lt;/activity&gt;
      &lt;activity
          android:name="com.burusoth.advertise.View_Advertisements"
          android:label="@string/title_activity_view__advertisements" &gt;
      &lt;/activity&gt;
      &lt;activity
          android:name="com.burusoth.advertise.Gadget_view"
          android:label="@string/title_activity_gadget_view"
          android:windowSoftInputMode="stateHidden" &gt;
      &lt;/activity&gt;
      &lt;activity
          android:name="com.burusoth.advertise.Activity_post_advertisements"
          android:label="@string/title_activity_activity_post_advertisements" &gt;
      &lt;/activity&gt;
      &lt;activity
          android:name="com.burusoth.advertise.Post_Advertisement"
          android:label="@string/title_activity_post__advertisement" &gt;
      &lt;/activity&gt;
      &lt;activity
          android:name="com.burusoth.advertise.Popup"
          android:label="@string/title_activity_popup" &gt;
      &lt;/activity&gt;
  
      &lt;activity
          android:name="com.burusoth.advertise.Google_Map"
          android:label="@string/title_activity_google__map" &gt;
      &lt;/activity&gt;
  
      &lt;meta-data
          android:name="com.google.android.maps.v2.API_KEY"
          android:value="AIzaSyAKCvpyR3v4YStDJDoibNgoblkdch0F254" /&gt;
  
  
  &lt;/application&gt;
  </code></pre>
  
  <p></p>
  
  <pre><code>my activity xml file
  
  
   &lt;RelativeLayoutxmlns: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=".Google_Map" &gt;
  
     &lt;fragment
          android:id="@+id/map"
          android:name="com.google.android.gms.maps.MapFragment"
          android:layout_width="match_parent"
          android:layout_height="match_parent"/&gt;
  &lt;/RelativeLayout&gt;
  </code></pre>
  
  <p>my Activity .java Activity file for calling map
      public class Google_Map extends Activity {</p>
  
  <pre><code>private GoogleMap googleMap=null;
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_google__map);
  
       try {
              // Loading map
              initilizeMap();
  
          } catch (Exception e) {
              e.printStackTrace();
          }
  }
  
  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
      // Inflate the menu; this adds items to the action bar if it is present.
      getMenuInflater().inflate(R.menu.activity_google__map, menu);
      return true;
  }
  
  private void initilizeMap() {
      if (googleMap == null) {
          googleMap =((MapFragment)getFragmentManager().findFragmentById(R.id.map)).getMap();
  
          // check if map is created successfully or not
          if (googleMap == null) {
              Toast.makeText(getApplicationContext(),
                      "Sorry! unable to create maps", Toast.LENGTH_SHORT)
                      .show();
          }
      }
  }
  
  @Override
  protected void onResume() {
      super.onResume();
      initilizeMap();
  }
  </code></pre>
  
  <p>}</p>