title: No resource identifier found for attribute adSize in package
body: <p>I am trying to add AdMob ads in my application.</p>
  
  <p>In the manifest I have:</p>
  
  <pre><code>&lt;uses-permission android:name="android.permission.INTERNET"/&gt;
      &lt;uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/&gt;
  
  &lt;meta-data android:name="com.google.android.gms.version"
          android:value="@integer/google_play_services_version" /&gt;
  
  
  &lt;activity android:name="com.google.android.gms.ads.AdActivity"
              android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize"
              android:theme="@android:style/Theme.Translucent" /&gt;
  </code></pre>
  
  <p>In the xml activity's layout I use:</p>
  
  <pre><code>&lt;com.google.android.gms.ads.AdView
          xmlns:ads="http://schemas.android.com/apk/res-auto"
          android:id="@+id/adView"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:layout_centerHorizontal="true"
          android:layout_alignParentBottom="true"
          ads:adSize="BANNER"
          ads:adUnitId="@string/id"&gt;
      &lt;/com.google.android.gms.ads.AdView&gt;
  </code></pre>
  
  <p>My java code in the main activity:</p>
  
  <pre><code>@Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
  
         mAdView = (AdView) findViewById(R.id.adView);
          adRequest = new AdRequest.Builder().build();
          mAdView.loadAd(adRequest);
  </code></pre>
  
  <p>Unfortunately this doesn't work and I receive this error</p>
  
  <blockquote>
    <p>error: No resource identifier found for attribute 'adSize' in package</p>
  </blockquote>