title: Android : sample implementation of google's headergridview
body: <p>I searched the Web and couldn't find anything but the source code of the class. I am still a beginner and I don't exactly understand how this class should be implemented </p>
  
  <p><a href="https://android.googlesource.com/platform/packages/apps/Gallery2/+/idea133/src/com/android/photos/views/HeaderGridView.java">https://android.googlesource.com/platform/packages/apps/Gallery2/+/idea133/src/com/android/photos/views/HeaderGridView.java</a></p>
  
  <p>Can someone provide me a coded implementation of such a class, say two headers, 4 views by header, one top header (above the grid view) , one bottom footer (below the grid view), as well as a demonstration of how to implement the filterable? (say by text within the view) </p>
  
  <p>Thanks a lot </p>