I have started developing on Odoo 13 just one week ago. and I am working on development of a module that is supposed to inherit timesheet_grid app and make some fundamental changes. now what I want to do is to develop a custom widget for list/tree view that takes a date, and display the elapsed time since the given date. for example if the given time is equal 18:20, and It's 19:30 It should display 01:10.

Actually I have tried to look for different solutions to make this work like QWeb, but apparently QWeb is not supported on on tree view. and I could not find any good documentation explaining how to make custom widgets, even the official documentation doesn't explain was not that deep.

That's why I am here hopping someone can provide me with a good example or documentation on how to make custom widgets for fields.

Thank you in advance and enjoy your evening!