How do you program a toolbar?

How do you program a toolbar ?
I mean how to access the code editor

Here is the User Guide topic for desktop toolbars:

There are also example projects in the Examples/Desktop folder.

Mr Lefebvre !! I cannot open any event like you teach in the tutorial !!!

Ok Mr Lefebvre I managed to find it while watching one of your videos on te same page.
Thank you Sir.