Devolutions.AvaloniaTheme.DevExpress 2026.8.10

Custom Avalonia Themes developed by Devolutions

DevExpress Theme [Work in Progress]

This theme is currently based on Avalonia.Themes.Fluent, both as a fallback for any controls not covered yet and as starting point for our (somewhat simplified) style definitions targeting DevExpress Winforms look.

While we are prioritizing controls for Devolutions Remote Desktop Manager, we welcome contributions from the Avalonia community to add more DevExpress-style controls.

• Installation
• Styled Controls
  • ✅ Available in the current build
    • AutoCompleteBox
    • Button
    • ButtonSpinner
    • Calendar
      • CalendarButton
      • CalendarDatePicker
      • CalendarDayButton
      • CalendarItem
    • CheckBox
    • ColorPicker
    • ComboBox
      • ComboBoxItem
    • DataGrid
    • EditableComboBox (Custom control)
    • Expander
    • ListBox
      • ListBoxItem
    • NumericUpDown
      • ButtonSpinner
    • RadioButton
    • ScrollViewer
      • ScrollBar
    • Separator
    • TabControl
      • TabItem
    • TabPane
    • TagInput (Custom control (Ursa))
    • TextBox
    • TreeView
      • TreeViewItem
    • Window
  • 🚧 In progress ...
    • small improvements & fixes, some code cleanup
    • ContextMenu
    • SplitButton
  • 🔮 Next on the road map ...
    • vertical tabs

Installation

Avalonia 12 required. Packages 2026.6.17-avalonia12 and later require Avalonia 12. The last stable release compatible with Avalonia 11 is 2026.6.16.

Install the Devolutions.AvaloniaTheme.DevExpress package via NuGet:

Install-Package Devolutions.AvaloniaTheme.DevExpress

or .NET

dotnet add package Devolutions.AvaloniaTheme.DevExpress

In your App.axaml, replace the existing theme (e.g. <FluentTheme /> or <SimpleTheme />) with the DevExpress theme:

<Application ...>
  <Application.Styles>
     <DevolutionsDevExpressTheme />
  </Application.Styles>
</Application>

Note: Some global Styles will also be loaded by default, you can opt out by setting GlobalStyles to false (<DevolutionsDevExpressTheme GlobalStyles="False" />). GlobalStyles are also available as a separate tag <DevolutionsDevExpressThemeGlobalStyles /> to cover scenarios where consumers would like to scope them to some control instead of including them globally. This is may be necessary to prevent styles from "bleeding out" in cases where that might be undesirable.

Menu pack (menu controls only)

Use the menu pack when you only want DevExpress menu styling but not the full <DevolutionsDevExpressTheme /> (e.g. to give consistent Menu chrome to custom-branded sections of your app).

<Application ...>
  <Application.Styles>
    
    <FluentTheme />

    
    <StyleInclude Source="avares://Devolutions.AvaloniaTheme.DevExpress/Controls/MenuPack.styles.axaml" />
  </Application.Styles>
</Application>

Exact menu pack URI:

avares://Devolutions.AvaloniaTheme.DevExpress/Controls/MenuPack.styles.axaml

Prerequisites and caveats:

• FluentTheme must be loaded application-wide, in Application.Styles — not scoped to a subtree. Adding <FluentTheme /> to the Styles of a Window, UserControl, or other container is not sufficient, even though the resource appears reachable from that subtree. The pack reuses Fluent's MenuScrollViewer control theme, which is resolved when the menu template is built; if FluentTheme is not application-wide this fails with an InvalidCastException during template construction. The exception surfaces on any menu — including a single-item menu that never needs to scroll — and its message does not mention scrolling, so it is easy to misdiagnose. If you see an unexplained InvalidCastException when a menu first opens, check this first.
• The pack reuses the Fluent base control templates and deliberately inherits a small set of keys from the host so menus still feel native to the surrounding app (see "Inherited from the host" below).
• This pack includes styling for ContextMenu, MenuFlyoutPresenter, Menu, MenuItem, Separator, and menu-specific helper styles (Menu.styles.axaml, Separator.styles.axaml, and the MenuItem Svg icon CSS styles).
• If you need full control coverage, use <DevolutionsDevExpressTheme /> instead.

Resource contract

All menu tokens live in a single shared file, Accents/MenuResources.axaml, which is included by both the full theme and the menu pack. There is one source of truth, so the pack can never drift from the full theme.

Two rules make the pack safe to layer over a host theme you do not control:

1. Every key the pack owns is prefixed DevExMenu — it cannot collide with, or be silently overridden by, the host theme's keys.
2. Values are pinned literals, never aliases. Menu tokens do not resolve through generic theme-wide or Fluent-owned keys. A host theme that redefines e.g. MenuFlyoutPresenterBorderThemeThickness or FlyoutThemeMaxWidth cannot move menu visuals.

Inherited from the host (by design):

Typography is pinned, not inherited. DevExMenuFontFamily / DevExMenuFontSize / DevExMenuFontWeight are owned by the pack. The point of the pack is that menus in a branded or opted-out section still match the platform-themed menus elsewhere in the same app; inheriting the host's font defeated that, because the branded section rendered its menus in the branded font and size. Pinning also keeps menu geometry identical across hosts.

The pack styles menu content only. It deliberately does not ship a Separator ControlTheme: that resource is keyed {x:Type Separator}, so merging it would restyle every separator in your app rather than just menu ones. Menu separators instead reuse the host's separator template — which is identical across Fluent, MacOS, Linux and DevExpress — with every template-bound property pinned inside the menu-scoped selector. A guard test asserts that adding the pack leaves non-menu separators byte-identical.

Overriding a token. Because tokens are prefixed, you can retarget any single value without affecting the rest of your app:

<StyleInclude Source="avares://Devolutions.AvaloniaTheme.DevExpress/Controls/MenuPack.styles.axaml" />

<SolidColorBrush x:Key="DevExMenuSeparatorBrush" Color="#ff0000" />

Both rules are enforced by MenuPackContractTests in the visual test project, which asserts that every DevExMenu* token resolves identically under the full theme and under "pack over a foreign host", and that a hostile host theme cannot leak into any of them.

Styled Controls

Most of the images below are screenshots from the SampleApp test and demo pages - feel free to check out the code there for more detailed usage examples.

For an always up-to-date visual reference you can also browse the baseline screenshots.