bll 2018-9-1: Just thought I would try and create a new theme. Loosely based on adwaita dark. I have learned more about ttk themeing, found issues in my application code related to colors and themes. Uses graphics for the checkbuttons, radiobuttons and the notebook tab top color. Everything else is based on the clam theme.
::ttk::theme::awdark::setMenuColors .menuwidget
Sets the menu colors and also changes any checkbutton and radiobutton types to use thematic images. Side effect: The menu will have -hidemargin set to true.
::ttk::theme::awdark::setTextColors .textwidget
Sets the text widget colors.
::ttk::theme::awdark::setListboxColors .listboxwidget
Sets the listbox widget colors.
For the moment, available at: https://gentoo.com/tcl/awdark.tcl
The demo code to display the widgets is: https://gentoo.com/tcl/demottk.tcl
Please post comments in the comp.lang.tcl thread (active 2018-9-1): https://groups.google.com/d/topic/comp.lang.tcl/fkwlov3x2cA/discussion