egui Persistence: Save & Restore Settings with serde | Rust GUI Ep 23

Build a Settings App that saves and restores preferences across restarts using eframe persistence and serde serialization! Learn get_value(), set_value(), the save() method, and the persistence feature flag. Student code: https://github.com/GoCelesteAI/egui_persistence/tree/main What You'll Learn: - #[derive(Serialize, Deserialize)] to make app state serializable - eframe::get_value() to load saved state from storage - eframe::set_value() to save state to storage - fn save(&mut self, storage) method on the App trait - eframe::APP_KEY as the default storage key - CreationContext for initialization with saved data - persistence feature flag in Cargo.toml - Dark/light theme toggle with ctx.set_visuals() - Slider and checkbox settings with Grid layout - Reset to defaults pattern Timestamps: 0:00 Intro 0:12 App Preview 0:22 What We're Building 0:54 Create Project & Cargo.toml (persistence + serde) 1:18 main.rs — CreationContext with MyApp::new(cc) 1:52 app.rs — Imports & serde Derive 2:18 MyApp Struct with Serializable Fields 2:34 Default Implementation 3:12 new() Constructor — Loading from Storage 3:52 impl App — save() with set_value 4:16 update() — Dark/Light Theme Toggle 4:58 Settings Grid — Username, Checkboxes, Sliders 6:18 Reset to Defaults Button 6:32 cargo build & Neo-tree H (Hidden Files) 7:00 App Demo (Close & Reopen to Verify Persistence) 7:54 Recap 8:34 Next Episode Series: Learn egui in Neovim Part of a 36-episode series teaching Rust GUI development with egui, coded entirely in Neovim with Neo-tree. Tags: egui, rust, gui, persistence, serde, serialize, storage, tutorial, neovim, settings app, save state, get_value, set_value, eframe