For simple programs, tkinter is a lot more straightforward and easier to get started with . Plus its library is built into the standard python installation package. Kivy offers more flexibility and is more complicated, but it also has support for mobile (android + IOS).
Read moreCan I use Kivy and tkinter together?
It probably is possible to run Kivy in an opengl context within a tkinter window, but there’s no support for this and you’d have to write a fair amount of code to get it to work. Essentially you’d need to write a tkinter backend provider for the Kivy window.
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