WinUI 3 Parity and WPF differences

Fluence.Wpf follows the Windows 11 Fluent visual language and many WinUI 3 control names. It remains a WPF library. This page helps when moving a WinUI example into a WPF application or deciding whether a familiar WinUI pattern is available.

What maps directly

• Core control names and roles include Button, NavigationView, TabView, ContentDialog, InfoBar, TeachingTip, AutoSuggestBox, NumberBox, DatePicker, TimePicker, and ColorPicker.
• Common color and brush names follow WinUI-style families such as TextFillColor*, ControlFillColor*, AccentFillColor*, and CardBackgroundFillColor*.
• Light, Dark, and High Contrast are supported, with live theme and accent updates through published WPF resources.
• ThemeResourceExtension and ThemeDictionary provide WPF equivalents of theme-aware markup and per-theme values.

The control catalog and theme reference define the actual shipped surface. The public API and resource-key baselines in the repository are the exact inventories.

Differences to account for

Concern	Fluence.Wpf behavior
Runtime	Controls are WPF types and templates. A consuming app does not need the Windows App SDK.
XAML namespace	Use xmlns:fluence="http://schemas.fluencewpf.com"; write {fluence:ThemeResource Key} with the prefix.
App resources	ApplicationThemeManager.Apply publishes a WPF merged-dictionary stack. Use DynamicResource or ThemeResource for live values.
Per-control keys	The library publishes application-wide roles, but no WinUI-style key per control state. Replace a specific control template to restyle that state.
Acrylic surfaces	WPF has no equivalent per-element backdrop brush, so acrylic resource roles are painted fallback colors. Window backdrop requests use the available Windows DWM or legacy path.
Navigation	NavigationView derives from WPF Selector; its page host belongs in NavigationView.Content, and the app owns navigation history.
Date picker	The Fluence picker has its own selected-date API and is not a subclass of WPF DatePicker.
Text and images	Fluence TextBlock and Image are templated controls rather than subclasses of the native WPF elements.
Password entry	Native WPF PasswordBox is styled implicitly and extended with attached properties because it is sealed.

Visual and platform boundaries

The control templates use Fluent colors, geometry, elevation, focus, and animation resources. Window chrome is translated through WPF WindowChrome and Windows interop. Windows 11 can supply Mica, Tabbed, Acrylic, and rounded-corner behavior; Windows 10 and high contrast use documented fallbacks. See compatibility.

Where WinUI uses a compositor feature that WPF does not expose, the library chooses a WPF behavior and records accepted limitations in known issues. For a specific control, inspect the gallery example beside the corresponding control source and template. This is the most reliable way to assess parity for an interaction you plan to use.