title: Cannot reslolve method onSectionAttached(int)
body: <p>I'm following along here: <a href="https://youtu.be/ZdBe_tPOY-A?t=4m53s" rel="nofollow">https://youtu.be/ZdBe_tPOY-A?t=4m53s</a> and can't figure out why Android Studio is giving me an error on line 47: <code>OnSectionAttached(1);</code>. It's saying 'Cannot resolve method <code>OnSectionAttached(int)</code>, while it worked perfectly fine in the video (<code>he didn't have to define the method</code>). </p>
  
  <p>Here's the file AboutFragment.java:</p>
  
  <pre><code>package trade.android.example.com.stitch;
  
  
  import android.app.Activity;
  import android.os.Bundle;
  import android.support.annotation.Nullable;
  import android.support.v4.app.Fragment;
  import android.view.LayoutInflater;
  import android.view.View;
  import android.view.ViewGroup;
  
  /**
   * Created by FiringBlanks on 7/12/2015.
   */
  
  public class AboutFragment extends Fragment {
  
  public static AboutFragment newInstance(){
  
      AboutFragment fragment = new AboutFragment();
      return fragment;
  }
  
  public AboutFragment(){
  
  }
  
  
  @Nullable
  @Override
  public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
      View rootView = inflater.inflate(R.layout.fragment_about, container, false);
      return rootView;
  }
  
  @Override
  public void onAttach(Activity activity) {
      super.onAttach(activity);
  
      ((MainActivity) activity).onSectionAttached(1);
  
  }
  }
  </code></pre>