The Fl_OpDesk project can either be added to FLTK, or installed as a subdirectory either inside your own project, or in a separate directory that all your projects can refer to.Just be sure to compile with the -I (include) flag pointing to where the Fl_OpDesk directory is, and link in "Fl_tree.a" left in the Fl_OpDesk main directory after doing a 'make'.
Installing Fl_OpDesk Into Your Project's Directory
Here's an example of how to install Fl_OpDesk into your project's own directory:*** TO BE DONE -- NOT YET WRITTEN ***