title: How to generate navigation tree in doxygen output?
body: <p>If you've used javadoc and then come to doxygen, you may know what I mean when I say I miss the hierarchical (frame-based) view that made jumping from class to class and method to method easy.  (For those who haven't seen it, imagine a tree-navigator in an IDE or over a filesystem). </p>
  
  <p>How can I get Doxygen to include a navigation tree, if it's even possible?</p>
  
  <p>A <a href="https://stackoverflow.com/questions/165451/suggest-a-good-doxygen-stylesheet">similar question was asked</a> in October, but that was just about stylesheet alternatives and only one turned up.  I think I'm looking for something more major.</p>