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0 pointsneobrain1y ago0 comments

> The big thing that sold me on QML over Widgets - other than the latter being the redheaded step child by this point - was implementing hot reloading. Having the entire UI completely refresh when changing the QML is definitely a nice coming from browser frontend, especially given Rust compile times.

Interesting, are there any public examples on how to implement this? All tools I've seen to do this seemed to be commercial offerings, though maybe implementing it in an existing application is easier than I think.

actually now that I'm looking again I found https://github.com/patrickelectric/qhot, which also looks promising

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throwup2381y ago

It’s very easy to implement a naive version. It only took me a few hours with the help of GPT/Claude and most of that was figuring out how to save and restore all window positions.

All it is is Rust’s notify listening for any changes in my QML directory and calling a C++ function on QQmlEngine: https://pastebin.com/08QKu84H

It'll require a bit more work once I'm loading multiple root QML files but for now it works great. It doesn't explicitly restore any state, however, but I store most of my UI state in Settings and a custom component that syncs arbitrary JSON values to Sqlite so the previous state is automatically restored when the QML is reloaded.

neobrainOP1y ago

Ah, I somehow assumed more magic would be needed, but indeed it's really as simple as deleting the top-level widget and recreating it. And then repopulating the properties is what gives it the illusion of being dynamically live-patched.

I'll take a shot at implementing this in some of my code as well. Thanks!

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