How do you define a main page hierarchy in Doxygen? - doxygen

Question

On this Doxygen generated help page http://api.fluffyunderware.com/curvy/index.html, there is a hierarchical documentation index for the main page and a table of contents. How do I replicate this capability in my own documentation?
Here is a screenshot of the mentioned page:

Answer 1

On the example web page in your link, there are two main panes: on the left is an automatically-generated hierarchical index (what Doxygen calls a "treeview"), and on the right is a manually-generated table of contents. These are produced using different methods.
Index
To create an automatically-generated hierarchical index, edit your Doxyfile, and make sure the following tag appears as shown:
GENERATE_TREEVIEW = YES
The default value for the GENERATE_TREEVIEW tag is NO.
This will cause the index to appear in the left pane.
Table of Contents
The Table of Contents in the right pane can be generated manually as follows.
Use nested indented bulleted lists in your markdown to manually create a multi-level hierarchy, and use #ref (or \ref) command tags to create hyperlinks.
Here is an excerpt from the doxygen documentation for my own project. I put this page in a document named "pages.dox", and added a reference to "pages.dox" to the INPUT tag in the Doxyfile.
/*! #page users_guide STFishFinder API User's Guide
#par Table of Contents
- #ref users_guide
- #ref black_box
- #ref api_overview
- #ref stfishfinder_api
- #ref wrappers
- #ref ios_fishfinder_api
- The Fish Finder API for Android <!-- #ref android_fishfinder_api -->
- The Fish Finder API for CLI <!-- #ref windows_fishfinder_api -->
- The Fish Finder API for Linux <!-- #ref linux_fishfinder_api -->
- #ref porting
- #ref how_to
- #ref how_to_connect
- Flow of Information Overview <!-- #ref flow_of_info -->
- Advanced Gain Settings <!-- #ref gain_how_to -->
- How To Use the Depth Alarms <!-- #ref depth_alarms_how_to -->
- #ref simulator_how_to
- Updating the Black Box Firmware <!-- #ref firmware_update -->
- #ref best_practices
*/
The page for the above excerpt is rendered by Doxygen as shown in the below screenshot:
Note that some of the entries in my table of contents are not links (e.g. "The Fish Finder API for Android"). This is because my API documentation is not finished yet, so I created "placeholders" for pages that haven't been written yet. I commented out the #ref links for these using HTML-style comment tags.
See also
Online documentation for Doxygen's #ref command is at this link.
Documentation for Doxygen's
markdown support is at this link.