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# What it does
Addition of a new system of theme plugins which allow the user to use
different rules engine to compute the style for the available
specialised widget style.
# How to use
Create a engine implementing the trait `ThemePlugin` and `ThemeStyle<S:
StyleStruct>` and implement the necessary methods, then register this
way (example for `ButtonStyle`):
```ui.add_theme::<ButtonStyle>(&mycustomengine);```
Now all button will call the `ThemeStyle<ButtonStyle>` method to compute the correct style and later use the cached value to avoid the costly computation.
If no valid `ThemeStyle<S>` or engine is available then it fallback to the default style.
* Closes part of <https://github.com/emilk/egui/issues/3284>
* [x] I have followed the instructions in the PR template
---------
Co-authored-by: adrien <221212@umons.ac.be>
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-authored-by: Lucas Meurer <hi@lucasmerlin.me>
* [x] I have followed the instructions in the PR template
Remove clippy lint groups already covered by `all` (`complexity`,
`perf`, `suspicious`, and the misspelled `correctnesss`), and two
individual lints covered by the `cargo` group (`negative_feature_names`,
`wildcard_dependencies`).
Add `publish = false` to the two internal crates that were missing it
(`popups`, `egui_tests`), which silences the
`clippy::cargo_common_metadata` warnings.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
