android - Master/Detail Flow (Two Pane) Layout List Subitems -

i'm using this tutorial build android project. uses master-detail flow (two pane) layout tablets. provides list fragment items list. uses android.r.layout.simple_list_item_activated_1 layout show list of item on left, , uses webview on right show dummy content.

now want add description list items (i beleive called item/subitem listview) liko so:

http://i.stack.imgur.com/kb4ew.jpg

the problem is, can't achieve kind of list subitems using

public static map<string, dummyitem> item_map = new hashmap<string, dummyitem>(); 

array kind of structure:

additem(new dummyitem("1", "title", "file:///url.html")); 

the question is: how can add needed functionality project modifying basic master/flow layout webview dummycontent representing?