How to add multiple UI skin/theme and switch between them from browser?

I want to add multiple themes for my project so that they can be switched by the user at runtime. I want to implement something like in this example where it provides multiple themes and we can switch themes from a dropdown.  Mendix Theme Viewer How to create and set these multiple themes in Mendix? How can I implement the theme switcher which allows user to switch between available themes? Mendix Modeler version is: 7.22.2 and it uses Atlas UI instead of Mendix UI framework.  In this version the “theme zip file” option to add multiple theme is deprecated.
1 answers

a lot like this question:

we discovered a way to change swap CSS files using a widget, I’ll ask the dev to post his answer :D 

we ended up using:

StyleSheet switcher Widget