Demo Product Shell

RoyalApps.RoyalTerminal.Avalonia.App is the reusable end-user style terminal application shell. samples/RoyalTerminal.Demo is now a thin executable launcher that configures Avalonia, owns the Application/theme bootstrap, and opens the shared MainWindow.

Shell Layout

The shared shell is intentionally compact:

• terminal content is the primary surface;
• the top command bar is placed inside the extended titlebar;
• the tab strip stays visible and scannable;
• a left rail exposes high-frequency panels and actions;
• settings, profiles, command history, capture, and diagnostics are available but not dominant;
• diagnostics expose selectable Ghostty/runtime text plus the runtime event-log count, timeline, and clear action;
• replay playback and seek controls appear in the status bar only while replay mode is active;
• most low-frequency settings live in the native/menu surface or settings panel.

The shell avoids large marketing-style sections and nested card surfaces. Styling is defined in resource dictionaries under src/RoyalTerminal.Avalonia.App/Styles.

Native Menus

On macOS, application-level commands belong in the application menu, not the window menu. The demo application declares the application native menu in samples/RoyalTerminal.Demo/App.axaml so Avalonia sees it during startup and does not install the default About Avalonia item. ApplicationNativeMenuFactory then binds the declared menu items to the main ViewModel commands:

• About RoyalTerminal;
• Preferences;
• Quit RoyalTerminal.

Window-level menus contain Shell, Edit, View, Session, Window, and Help actions. They expose the same low-frequency command surface that is available from the shell UI: command-history suggestions, profile refresh and launch, settings, settings profile actions, apply/save, font browsing, text-highlight rule creation, shell panel visibility, titlebar search visibility, status bar visibility, theme and shader controls, diagnostics, capture and replay controls, pane navigation, tab switching, and snapshot actions. Per-rule text-highlight removal remains contextual in the settings panel because each rule owns its own remove command. This prevents the default Avalonia application menu from surfacing an About Avalonia item. About and Quit stay application-level commands; Preferences also appears in the View menu as a cross-platform fallback.

The app also sets:

new MacOSPlatformOptions
{
    DisableDefaultApplicationMenuItems = true,
}

Extended Titlebar

The shared MainWindow uses Avalonia extended client area:

ExtendClientAreaToDecorationsHint="True"
WindowDecorations="Full"
ExtendClientAreaTitleBarHeightHint="-1"

The titlebar band is marked with WindowDecorationProperties.ElementRole="TitleBar" so the OS receives native drag, double-click, and titlebar gesture hit testing. Interactive controls placed inside the titlebar, such as search and New Tab, are marked with ElementRole="User" so they keep normal pointer and keyboard behavior. The -1 titlebar-height hint follows Dock's BrowserTabTheme sample: native chrome placement remains platform-managed, which keeps macOS traffic lights vertically centered, while RoyalTerminal keeps a compact titlebar command band.

The layout reserves space for macOS traffic lights and for right-side decoration margins:

• MacTrafficLightReserve;
• TitleBarRightDecorationReserve.

Settings Panel

The settings panel is styled as an integrated overlay rather than a heavy card. The overlay:

• clips to the available terminal host area;
• disables horizontal scrolling;
• constrains panel width and height;
• uses the shared terminal shell palette;
• keeps category navigation and content independent through the settings panel ViewModel state.

ViewModel Boundaries

The shared shell follows the repository MVVM rules:

• XAML defines layout and visuals;
• MainWindow owns top-level key bindings, native menus, and window metadata;
• MainView owns the visual terminal shell;
• MainWindowViewModel exposes commands and interactions;
• MainWindowController handles concrete window, terminal, storage, and menu orchestration;
• code-behind only initializes the window and activation.

Titlebar, menu, pane, settings, search, capture, and command-history actions all route through commands or ReactiveUI interactions.

Product Startup

The shared shell starts in resource-conscious mode:

• restore a saved workspace when available;
• otherwise open one terminal tab;
• start diagnostic tabs for every supported render mode only when ROYALTERMINAL_DEMO_START_ALL_RENDER_MODES=1 is set;
• disable session autostart in tests with ROYALTERMINAL_DEMO_DISABLE_SESSION_AUTOSTART=1.

Tests

Focused coverage:

• MainWindowViewModelFlowTests for titlebar role wiring, menu placement, command bindings, settings overlay sizing, and app title;
• MainWindowControllerModeStartupTests for startup mode, workspace restore, pane behavior, and active terminal surfaces;
• TerminalSettingsPanelLayoutTests and MainWindowControllerSettingsPanelTests for settings panel layout and state.