title: Android studio library dependency not showing up
body: <p>I went  to <strong>file -->app--> dependencies --> green plus sign</strong> and press on <strong>library dependency</strong>. Nothing show up. I trying to add the support v4 dependency so I can extend <strong>Fragment Activity</strong>. Now I having error cannot resolve symbol support.  </p>
  
  <pre><code>import android.support.v4.app.FragmentActivity;
  
  public class MainActivity extends FragmentActivity {
      ViewPager viewpager;
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);
          viewpager = (ViewPager) findViewById(R.id.pager);
          PagerAdapter padapter = new PagerAdapter(getSupportFragmentManager());
          viewpager.setAdapter(padapter);
      }
  }
  </code></pre>