is tk backend special?

Hello’all -

I am trying to develop my own toolbar and thought the easiest way to do
this was to define a new backend and change it in that file.
Matplotlib includes the ‘template’ backend as a start.
To get going, I copied the entire TkAgg backend into the template
backend and set the backend to ‘Template’ in the matplotlibrc file.
But now when I run pylab, it doesn’t work interactivly anymore.
When I just give a plot([1,2,3]), it draws the figure window but not the figure.
draw_if_interactive() doesn’t work either, even though interactive is set to True.
draw() does work and creates the correct figure.
Is Tk special ? I thought this should work.

Any help appreciated.