title: Unable to cast Action Provider to Share Action Provider
body: <p>Below is the code for my Activity </p>
  
  <pre><code>    import android.app.Activity;
      import android.os.Bundle;
      import android.support.v7.widget.ShareActionProvider;
      import android.view.Menu;
      import android.view.MenuItem;
  
      public class MainActivity extends Activity {
      private ShareActionProvider shareAction;
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
      }
  
      @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_main, menu);
          MenuItem item = menu.getItem(R.id.menu_settings);
          shareAction = (ShareActionProvider) item.getActionProvider();
          return true;
      }
  }
  </code></pre>
  
  <p>The Problem is that there is a cast error from ActionProvider to ShareActionProvider.Why it is so 
  below is activity_menu.xml</p>
  
  <pre><code> &lt;menu xmlns:android="http://schemas.android.com/apk/res/android" &gt;
  
  &lt;item
      android:id="@+id/menu_settings"
      android:orderInCategory="100"
      android:showAsAction="always"
      android:title="@string/menu_settings"
      android:actionProviderClass="android.widget.ShareActionProvider"
      /&gt;
  
  &lt;/menu&gt;
  </code></pre>