makepad-2.0-app-structure

Define a struct deriving Script and ScriptHook with a #[live] ui: WidgetRef field, call app_main!(App), define UI in script_mod!, and implement App::run to register widget modules before calling App::from_script_mod. Implement MatchEvent for actions and AppMain for event dispatch.

Rust calls Splash via script_eval! to update mod.state and trigger renders, or script_apply_eval! to patch widget properties. Splash calls back through inline handlers like on_click and on_render, while Rust reads widget actions in MatchEvent::handle_actions using ids! selectors.

Run the app with cargo run -p my-app -- --hot. The --hot flag watches script_mod! source files and refreshes the UI on save without recompilation, but it only applies to Splash DSL changes; Rust code changes still require a rebuild.

No, audio is not exposed to Splash scripting. All audio processing must happen in Rust using cx.audio_output and cx.audio_input callbacks, which run on a real-time thread. Use Arc<AtomicU64> to pass audio data safely to the UI thread.

handle_actions only fires if you call self.match_event(cx, event) inside your AppMain::handle_event implementation before forwarding the event to the widget tree. Omitting that call silently disables all MatchEvent trait methods.

Use the makepad_objc_sys crate to call NSStatusBar via msg_send, since Makepad has no built-in status bar API. Avoid the objc2 crate because it creates a conflicting NSApplication instance, and use LSUIElement in Info.plist instead of show_in_dock(false).