QT is a third party library that wraps the underlying OS primitives.
A really fancy tree view in JS is 10KB, maybe 15KB, given desktop+mobile support, proper accessibility, and good support for theming.
And that is if you are getting really fancy. A simple one is just some DIVs and a CSS animation for opening and closing.
That is assuming you even bother with JS, since you can do a treeview in the browser with CSS alone[1].
UI toolkits exist for the web as well, and they tend to be rather small, browsers ship with a lot of UI primitives after all!
The UI portion of code for my B2B web-app with all custom UI elements and with mobile+desktop support is around 100KB unminified.
Now the libraries I pull in to do the real time database streaming and authentication to my back end? Those dwarf the UI code (they are hundreds of KB each), but the native versions of those libraries are far larger (10x)[2], than the JavaScript equivalents.
> Would it blow your mind if I told you that you can create a complex treeview without having to use third-party libraries or reinventing half the wheel yourself?
The browser comes with a lot of wheels included, very few are getting re-invented unless someone wants indulge themself.
> To be clear I'm not saying that it's a bad idea per-se, I personally believe that the web is way too complicated as it is
Get rid of the weird things that happen to make advertising possible and most websites are pretty simple. Even complex web-apps are pretty easy to understand now days, though you'll have to learn whatever data-binding technique the dev team decided to use, but that is the same case for modern desktop applications.
[1]https://codepen.io/kobusvanwykk/pen/NqXVNQ
[2]https://stackoverflow.com/questions/41750553/what-is-the-est...
