LanMountainDesktop/docs/archive/ai/SETTINGS_WINDOW_DESIGN.md

Settings Window Fluent Shell Design

This document is the authoritative implementation note for the LanMountainDesktop settings window shell. General visual tokens still come from docs/VISUAL_SPEC.md and docs/CORNER_RADIUS_SPEC.md.

References

• Current host settings implementation in LanMountainDesktop/Views/SettingsWindow.axaml.
• ClassIsland SettingsWindowNew: titlebar navigation buttons, titlebar pane toggle, NavigationView width, right-side drawer.
• SecRandom v3 Avalonia SettingsView: titlebar search, restart action, NavigationView compact toggle, search result highlight.
• Awesome Design / Fluent style notes: quiet app surface, token-driven spacing, system material as backdrop instead of decorative panels.

Shell

• The settings window remains an independent top-level window opened through SettingsWindowService.
• The shell uses a 48 DIP custom titlebar and one FANavigationView as the main container.
• The titlebar left cluster is: Back, pane toggle, app/settings icon, window title.
• The titlebar center is a settings AutoCompleteBox search field.
• The titlebar right cluster is: restart prompt, more options, Windows caption-button spacer.
• The fallback pane toggle belongs in the titlebar, not the navigation footer.
• Content remains unframed: pages render directly in the FAFrame; drawers are the only side panel.

Navigation And Search

• FANavigationView.OpenPaneLength stays near 283 DIP and may scale within the existing responsive limits.
• Navigation history is local to the settings window; using Back does not close the window or affect the desktop shell.
• Search entries always include page-level descriptors.
• Built-in pages are also scanned for FASettingsExpander and FASettingsExpanderItem text.
• Selecting a search result navigates to its page, expands parent settings expanders, scrolls/focuses the target, and shows a short accent highlight.
• Plugin and generated pages are searchable at page level unless their controls are already loaded and can be scanned.

System Material

• SystemMaterialMode supports auto, none, mica, and acrylic.
• The default is auto.
• The implementation uses Avalonia Window.TransparencyLevelHint; it does not use WinUI SDK interop or private platform accessors.
• Auto mode uses this priority:
  • Windows 11: Mica, then AcrylicBlur, then Blur, then None.
  • Windows 10: AcrylicBlur, then Blur, then None.
  • Other systems or disabled transparency: None.
• The settings-window root brush remains translucent for material modes so it does not cover the OS backdrop.

Layout Rules

• Settings pages use ScrollViewer -> StackPanel.settings-page-container -> FASettingsExpander.
• Avoid nested surface cards inside the settings content area.
• Use dynamic design tokens for radius and colors.
• Widget root radius rules still follow DesignCornerRadiusComponent; settings shell internals use the smaller design radius tokens.