I don’t see much point in making GUI apps for desktop nowadays, especially since desktop usage is in decline compared to smartphones. If you still want to, I’d go with iced, which is in rust, and well designed.

I’d recommend learning either android jetpack-compose, or iOS app dev.

If you are interested into dipping your toes into rust land there is a library called Iced that I have used before. I at least like it better tham pyqt

This might be of interest for you, and its free PDF. From 2019 but still actual.

An Introduction to C & GUI Programming – the new book from Raspberry Pi Press

If you prefer non-kde apps, then consider Vala. It’s a young-ish language and it’s well suited for Gtk apps.

I’m going to agree with a lot of the other posters and say QT with QT creator. It’s a tested and well though out implementation. It’s signals and slots event system is straight forward and easy to learn.

Whatever route you take learn Model View Controller (MVC). It gets in the mindset of keeping your data model seprate from things that use the data and things that change the data.

https://en.m.wikipedia.org/wiki/Model–view–controller

Beeware!

Toga is a blessing. You can make apps for Windows, MacOS, Android, iOS, Linux and Web - all with the same codebase!

I’ve worked with GUIs on python for a couple of years, we used PyQt, which is a python wrapper for Qt which is a C++ library for GUIs. It’s fairly straightforward and easy to get something up on the screen in no time.

However from parts of your comment it seems you want to implement your own graphics library, and that is a lot harder to do.

Also you mentioned legacy hardware, not sure how legacy it would be. Python should run on most things people would call legacy nowadays, but there’s definitely an overhead that could be felt if you’re trying to run this on an embebed system or a REALLY old (as in 90s/00s era) computer.

You also mentioned mobile, I don’t think PyQt can be compiled to mobile easily, nor do I think you should even if you manage to (been there, done that, not a happy time). Desktop and Mobile GUIs are very different, realistically if you want something that works well on both mobile and desktop with the same codebase the easiest approach is web UI.

Try egui.

I just know I’m gonna get raked, but try Lazarus. A Delphi clone using the FreePascal compiler. Has a framework similar to the VCL, but has pluggable backends. Qt, GTK, Windows, Cocoa, and a native one, though I’m not sure of its maturity. Component programming that is relatively easy to extend.

Bless you for doing god’s work. We need more GUI developers and a better ecosystem as a whole.

That said, it’s pretty shite right now. Your established options are GTK and Qt. Qt uses C++ and I believe GTK uses C. I’ve only really looked briefly into Qt development, and it looks like there are bindings to Rust.

That said, I’m a firm believer that doing GUIs through code is an inefficient, cumbersome, and antiquated process that should be replaced with more visual alternatives, like we see in Godot Engine.

If you are in sciences, and happy to learn a new PL, I think you ll enjoy functional programming, even if it is not the most popular way. https://ocaml.org/docs/is-ocaml-gui-yet

My goal is to code basic buttons and understand how operating systems implement the way they draw windows for applications.

So do you want to program a GUI yourself, and not using a library, correct ?

Unpopular opinion: Just make a web app.

I’ve been using Flutter, I like how it’s cross-platform, mostly. I’ve generally built things for Android, but the desktop (Linux and Windows) and web versions usually compile fine with no tweaking. Couldn’t speak to the iOS versions as I can’t be arsed to jump through Apple’s hoops. You can make a nice looking app with it for whichever platform you’re targeting.

It’s very well supported, lots of examples, well documented. Not as much out there as Python for examples and troubleshooting, but not bad.

Slint

I really like Slint.

It has Python bindings, tho you wouldn’t know it from the docs as it’s brand new bindings.

However, it does WORK, and it works well.

Just look for python files in the examples and reference the slint docs (it uses its own UI lang for that stuff anyway).

I’m currently making an application in Python using Slint, and I really like it.

It also supports embedded systems, the web, and multiple languages, AND since it has its own UI lang, you can reuse parts of your UI code across different codebases

It seems to suit your use case.

Godot

Other than that, I second Godot.

HOWEVER

Godot’s GD Script is not Python but rather a Python-like language. (in fact, in some ways, I’m glad it’s not; there are things I prefer in GD Script).

This is important as you may want to use specific Python libraries which won’t work with Godot!

You can, however, use GD Native to bind C++ code and thus C++ libraries, so you’ll still be able to get done whatever you need to get done.

Iced

If you’re not tied to Python, then I recommend the Rust library Iced as it is a very intuitive system. I really enjoy working with it.

Although, that said, Slint has great support for Rust, so maybe I’d recommend Slint anyway if you were gonna change language.

Warning Against Legacy

Avoid GTK, Qt, and TK at all costs imo. Also WinForms if ur on Windows.

They’re old and crusty, and their APIs suck to use, even modern versions, and despite being aged, they’re buggy still, not robust “tried-and-true” methods.

It’s also hard to do dynamic stuff with them.

Just not well designed systems. Important, valuable to know bc they’re used all over, but not well designed

Immediate

I would also try ImGUI.

It’s meant more for gamedev UIs rather than Apps themselves (tho I’ve made a couple in it)

BUT

It’s a totally different way of doing UI called “Immediate” bc you program the elements in a big loop, rather than event driven.

It’s interesting and worth trying as a learning experience

React

And ofc, the Javascript/Electron world is huge and React is very popular with lots of tools. At least read up on it.