Migrating WPF-UI (Lepoco) Controls to Uno Platform

Most of your WPF-UI styling survives the port to Uno Platform because both frameworks target the Fluent design system. Uno Platform ships Fluent-styled versions of Button, TextBox, NavigationView, InfoBar, and more out of the box, and Uno Toolkit covers additions like Card and Chip. This guide maps each WPF-UI control to its closest Uno Platform equivalent, flags what you rebuild, and shows how to switch the Fluent theme pack on.

Why This Migration Is Easier Than You Think

WPF-UI brings "the Fluent experience in your known and loved WPF framework." That design choice is what makes the Uno Platform port straightforward: both stacks target the same Fluent visual language. Once you add XamlControlsResources to your resources, the WinUI Fluent look becomes the default on every platform Uno renders to.

For a developer coming from lepoco/wpfui, the mental model does not change: you still write Fluent XAML, you just drop the ui: prefix and reach for WinUI or Uno Toolkit controls instead. Cross-platform reach is the deliverable.

The Control Mapping Table: WPF-UI to Uno Platform

WPF-UI's base controls (Page, ToggleButton, List) are standard XAML classes in Uno Platform and port unchanged once Fluent styles are enabled.

Lighting Up Fluent Styles in Uno Platform

WPF-UI asks you to merge ThemesDictionary and ControlsDictionary into your App.xaml. Uno Platform uses the same WinUI mechanism: add XamlControlsResources to your application resources.

<Application.Resources>
  <ResourceDictionary>
    <ResourceDictionary.MergedDictionaries>
      <xamlControls:XamlControlsResources />
    </ResourceDictionary.MergedDictionaries>
  </ResourceDictionary>
</Application.Resources>

For symbol icons, Uno.UI 4.7+ brings the Uno Fluent Symbols font implicitly via the Uno.Fonts.Fluent NuGet package. Reference glyphs through the SymbolThemeFontFamily resource:

<FontIcon FontFamily="{ThemeResource SymbolThemeFontFamily}"
          Glyph="&#xE117;"/>

Rebuilding the Three Controls That Do Not Map Directly

Snackbar

WinUI uses InfoBar for inline status messages. It does not auto-dismiss. For a WPF-UI-style transient snackbar, wrap InfoBar in a helper that sets IsOpen = true, starts a DispatcherTimer, and sets IsOpen = false when it fires. Keep the Severity-based coloring (Informational, Success, Warning, Error) so it feels consistent with WinUI.

MessageBox Helper

ContentDialog is the Uno Platform replacement. Build a static helper that mirrors the WPF-UI MessageBox API:

public static async Task<ContentDialogResult> ShowAsync(
    string title, string message, XamlRoot root)
{
    var dialog = new ContentDialog
    {
        Title = title,
        Content = message,
        PrimaryButtonText = "OK",
        CloseButtonText = "Cancel",
        XamlRoot = root
    };
    return await dialog.ShowAsync();
}

FluentWindow / Mica Backdrop

WPF-UI's FluentWindow gives you Mica and SnapLayout integration inside WPF. On Windows, Uno Platform exposes the Windows App SDK MicaBackdrop:

public MainWindow()
{
    this.InitializeComponent();
    SystemBackdrop = new MicaBackdrop
    {
        Kind = MicaKind.BaseAlt
    };
}

Resource-Key Migration

WPF-UI lets you override Fluent brushes like TextFillColorPrimaryBrush directly. In Uno Platform you reference the same WinUI theme resources (via XamlControlsResources), and you can override them using the lightweight styling pattern:

<Page.Resources>
  <SolidColorBrush x:Key="InfoBarInformationalSeverityBackgroundBrush"
                    Color="LightBlue"/>
</Page.Resources>

For Uno Toolkit controls (Card, Chip, NavigationBar, TabBar), the lightweight styling keys are documented per-control in the Toolkit docs.

When to Keep WPF-UI vs. Migrate

Keep WPF-UI If

• Your app ships only on Windows and you have no cross-platform roadmap
• You depend on SnapLayout or FluentWindow behavior tied to the Win32 HWND lifecycle
• Your DataGrid usage is heavy and WPF-UI's implementation is stable for you

Migrate to Uno Platform If

• You need macOS, Linux, Web, or mobile reach. WPF-UI is WPF-only.
• You want to keep Fluent aesthetics without writing a custom theme layer
• You are investing in a new control set and can consolidate on WinUI + Uno Toolkit instead of WPF + WPF-UI
• You want to accelerate the port with agent-driven tooling. Uno Platform ships Claude Code integration and Uno MCP servers that can scaffold pages and map controls directly from a WPF-UI source tree.

FAQ

Is WPF-UI supported cross-platform?

No. WPF-UI targets WPF, which is Windows-only.

Can I use Uno Toolkit controls alongside Fluent theming?

Yes. Uno Toolkit (Card, Chip, NavigationBar, TabBar) is designed to coexist with Fluent or Material styling.

Do I lose Mica and acrylic on non-Windows?

Yes. Mica is a Windows 11 system-backdrop feature (minimum: Windows 11 Build 22621) and falls back to a solid color everywhere else.

How do I handle WPF-UI's icon set?

Replace references with the SymbolThemeFontFamily resource backed by Uno.Fonts.Fluent. Glyph code points for the built-in symbols line up with WinUI's Symbol enum.

Does Uno Platform support NavigationView on all targets?

NavigationView is implemented for WASM, Skia, and Mobile. For mobile-first navigation ergonomics, Uno Toolkit also ships NavigationBar.