No,Category,Guideline,Description,Do,Don't,Code Good,Code Bad,Severity,Docs URL,Applies To,Status,Verified At
1,XAML,Use Avalonia XAML namespace,Avalonia has its own XAML namespace not WPF,xmlns= for Avalonia-specific namespace,WPF xmlns or UWP xmlns,"<Window xmlns=""https://github.com/avaloniaui"">","<Window xmlns=""http://schemas.microsoft.com/winfx/2006/xaml/presentation"">",High,https://docs.avaloniaui.net/docs/fundamentals/avalonia-xaml,avalonia 12,active,2026-08-13
2,XAML,Use compiled bindings with x:DataType,Enable compile-time binding validation,x:DataType on root or DataTemplate for compiled bindings,Reflection-based bindings in production,"<Window x:DataType=""vm:MainViewModel""><TextBlock Text=""{Binding Name}""/></Window>","<Window><TextBlock Text=""{Binding Name}""/> without x:DataType",High,https://docs.avaloniaui.net/docs/data-binding/compiled-bindings,avalonia 12,active,2026-08-13
3,XAML,Enable compiled bindings globally,Avalonia 12 enables AvaloniaUseCompiledBindingsByDefault by default so every binding requires x:DataType and remains trim-safe for Native AOT,Keep the Avalonia 12 default or set AvaloniaUseCompiledBindingsByDefault explicitly when documenting the project contract,Disable compiled bindings or rely on runtime binding resolution,<AvaloniaUseCompiledBindingsByDefault>true</AvaloniaUseCompiledBindingsByDefault>,<AvaloniaUseCompiledBindingsByDefault>false</AvaloniaUseCompiledBindingsByDefault>,High,https://docs.avaloniaui.net/docs/data-binding/compiled-bindings,avalonia 12,active,2026-08-13
4,XAML,Use #name shorthand for element-to-element bindings,Compiled bindings cannot resolve {Binding ElementName=...} - use the #name shorthand which relies on NameScope lookup,#name shorthand referencing x:Name controls in the same NameScope,ElementName binding inside a compiled-binding scope,"<TextBlock Text=""{Binding #SearchBox.Text}""/>","<TextBlock Text=""{Binding ElementName=SearchBox, Path=Text}""/> under compiled bindings",Medium,https://docs.avaloniaui.net/docs/data-binding/compiled-bindings,avalonia 12,active,2026-08-13
5,Styling,Use CSS-like selectors,Avalonia uses selectors not implicit styles,Selectors targeting control types classes and pseudoclasses,WPF-style implicit Style with TargetType,"<Style Selector=""Button.primary""><Setter Property=""Background"" Value=""Blue""/></Style>","<Style TargetType=""Button""> without Selector",High,https://docs.avaloniaui.net/docs/styling/selectors,avalonia 12,active,2026-08-13
6,Styling,Use pseudoclass selectors for states,Target control states with colon syntax,:pointerover :pressed :focus for interactive states,VisualStateManager or Triggers,"<Style Selector=""Button:pointerover""><Setter Property=""Opacity"" Value=""0.8""/></Style>",<VisualStateManager> for hover effects,Medium,https://docs.avaloniaui.net/docs/styling/pseudoclasses,avalonia 12,active,2026-08-13
7,Styling,Use nesting selectors,Child and descendant combinators for scoped styles,> for direct child and space for descendant,Flat selectors that match too broadly,"<Style Selector=""StackPanel > Button""><Setter Property=""Margin"" Value=""4""/></Style>","<Style Selector=""Button""> that affects all buttons unintentionally",Medium,https://docs.avaloniaui.net/docs/styling/style-selector-syntax,avalonia 12,active,2026-08-13
8,Styling,Use StyleInclude for modularity,Split styles into separate AXAML files,StyleInclude to import themed resource files,All styles in a single monolithic App.axaml,"<StyleInclude Source=""/Styles/ButtonStyles.axaml""/>",1000+ line App.axaml with all styles,Medium,https://docs.avaloniaui.net/docs/styling/styles,avalonia 12,active,2026-08-13
9,Styling,Use Fluent or Simple theme,Built-in Avalonia themes,FluentTheme or SimpleTheme as base,Custom theme from scratch,<FluentTheme/>,Building all control templates manually,High,https://docs.avaloniaui.net/docs/styling/themes,avalonia 12,active,2026-08-13
10,Styling,Use theme variants for dark mode,Switch between light and dark,RequestedThemeVariant for theme switching,Hardcoded colors ignoring theme variants,Application.Current.RequestedThemeVariant = ThemeVariant.Dark;,Manually changing every brush for dark mode,Medium,https://docs.avaloniaui.net/docs/styling/themes,avalonia 12,active,2026-08-13
11,Controls,Use DataGrid for tabular data,DataGrid is a separate Avalonia.Controls.DataGrid NuGet package and requires its theme StyleInclude in App.axaml,DataGrid after adding package and StyleInclude for the matching theme,Custom Grid layouts for tabular data or DataGrid without the theme StyleInclude,"<DataGrid ItemsSource=""{Binding Items}"" AutoGenerateColumns=""False""/> with <StyleInclude Source=""avares://Avalonia.Controls.DataGrid/Themes/Fluent.xaml""/> in App.axaml",<DataGrid/> with no package reference or no StyleInclude (renders unstyled),Medium,https://docs.avaloniaui.net/docs/reference/controls/datagrid/,avalonia 12,active,2026-08-13
12,Controls,Use TreeView with TreeDataTemplate,Avalonia uses TreeDataTemplate for hierarchical data - HierarchicalDataTemplate is WPF only,TreeDataTemplate inside TreeView.ItemTemplate with ItemsSource pointing at child collection,HierarchicalDataTemplate copied from WPF or nested ItemsControls,"<TreeView ItemsSource=""{Binding Nodes}""><TreeView.ItemTemplate><TreeDataTemplate ItemsSource=""{Binding Children}""><TextBlock Text=""{Binding Name}""/></TreeDataTemplate></TreeView.ItemTemplate></TreeView>",<TreeView><TreeView.ItemTemplate><HierarchicalDataTemplate/></TreeView.ItemTemplate></TreeView> // HierarchicalDataTemplate does not exist in Avalonia,High,https://docs.avaloniaui.net/docs/reference/controls/treeview-1,avalonia 12,active,2026-08-13
13,Controls,Use NativeMenu for platform menus,Native menu bar on macOS and desktop,NativeMenu for cross-platform menu bar,Custom menu implementation per platform,"<NativeMenu.Menu><NativeMenu><NativeMenuItem Header=""File""/></NativeMenu></NativeMenu.Menu>",Custom menu bar control for each platform,Medium,https://docs.avaloniaui.net/docs/reference/controls/nativemenu,avalonia 12,active,2026-08-13
14,Data Binding,Implement INotifyPropertyChanged,Standard .NET property notification,INotifyPropertyChanged or CommunityToolkit.Mvvm,Properties without change notification,[ObservableProperty] private string _name;,public string Name { get; set; } without notification,High,https://docs.avaloniaui.net/docs/data-binding/inotifypropertychanged,avalonia 12,active,2026-08-13
15,Data Binding,Use ObservableCollection for lists,UI updates on collection changes,ObservableCollection<T> for bound collections,List<T> for ItemsSources,ObservableCollection<Item> Items { get; } = new();,List<Item> Items { get; set; },High,https://docs.avaloniaui.net/docs/data-binding/inotifypropertychanged,avalonia 12,active,2026-08-13
16,Data Binding,Use binding to named controls,Element-to-element binding with # syntax,#ElementName.Property for cross-element binding,Code-behind for element references,"<TextBlock Text=""{Binding #slider.Value, StringFormat='{}{0:F0}'}""/>",Code-behind ValueChanged handler to update TextBlock,Medium,https://docs.avaloniaui.net/docs/data-binding/introduction-to-data-binding,avalonia 12,active,2026-08-13
17,Data Binding,Use converters or FuncValueConverter,Transform data for display,FuncValueConverter for simple inline conversions,Complex IValueConverter classes for trivial transforms,"public static FuncValueConverter<bool, IBrush> BoolToColor = new(b => b ? Brushes.Green : Brushes.Red);",Full IValueConverter class for bool to color,Medium,https://docs.avaloniaui.net/docs/data-binding/how-to-create-a-custom-data-binding-converter,avalonia 12,active,2026-08-13
18,Cross-Platform,Use platform-specific code carefully,Isolate platform code behind abstractions,Interface + platform implementation pattern,#if directives scattered through ViewModels,IPlatformService with platform-specific implementations,#if WINDOWS ... #elif LINUX ... in ViewModel,Medium,https://docs.avaloniaui.net/docs/guides/building-cross-platform-applications/,avalonia 12,active,2026-08-13
19,Cross-Platform,Test on all target platforms,Rendering and behavior varies across platforms,CI testing on Windows macOS and Linux,Testing only on development platform,GitHub Actions matrix with windows-latest ubuntu-latest macos-latest,Testing only on Windows assuming cross-platform works,High,https://docs.avaloniaui.net/docs/guides/building-cross-platform-applications/,avalonia 12,active,2026-08-13
20,Cross-Platform,Handle platform file paths,Path separators differ across OS,Path.Combine and Environment.SpecialFolder,Hardcoded backslashes or forward slashes,"Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), ""MyApp"")","@""C:\Users\data\config.json""",Medium,https://docs.avaloniaui.net/docs/guides/building-cross-platform-applications/dealing-with-platforms,avalonia 12,active,2026-08-13
21,Cross-Platform,Use Avalonia asset system,Platform-agnostic resource loading,avares:// URI scheme for embedded resources,File system paths for assets,"<Image Source=""avares://MyApp/Assets/logo.png""/>","<Image Source=""C:/images/logo.png""/>",High,https://docs.avaloniaui.net/docs/fundamentals/including-assets,avalonia 12,active,2026-08-13
22,Performance,Use virtualization for large lists,Only render visible items,ListBox and ItemsRepeater with virtualization,Non-virtualizing ItemsControl for large lists,"<ListBox ItemsSource=""{Binding LargeList}""/>",<ItemsControl><StackPanel> for 10K items,High,https://docs.avaloniaui.net/docs/reference/controls/listbox,avalonia 12,active,2026-08-13
23,Performance,Avoid unnecessary bindings,Each binding has overhead,Bind only properties that change,Binding static labels and headers,"<TextBlock Text=""{Binding DynamicTitle}""/> but static: <TextBlock Text=""Settings""/>","<TextBlock Text=""{Binding SettingsLabel}""/> for constant string",Low,https://docs.avaloniaui.net/docs/data-binding/introduction-to-data-binding,avalonia 12,active,2026-08-13
24,Performance,Set bitmap interpolation mode on scaled images,RenderOptions.BitmapInterpolationMode controls image scaling quality vs cost; default may look aliased on upscaled or downscaled bitmaps,RenderOptions.SetBitmapInterpolationMode tuned to the use case,Default interpolation on scaled images that look blurry or aliased,"RenderOptions.SetBitmapInterpolationMode(image, BitmapInterpolationMode.HighQuality);",Image scaled with Stretch and no interpolation hint set,Low,https://docs.avaloniaui.net/docs/concepts/image-interpolation,avalonia 12,active,2026-08-13
25,Performance,Profile with Avalonia DevTools,Built-in diagnostic tools,DevTools for visual tree and binding inspection,Console.WriteLine debugging,Attach DevTools in debug mode with F12,Print statements to debug layout issues,Medium,https://docs.avaloniaui.net/docs/guides/implementation-guides/developer-tools,avalonia 12,active,2026-08-13
26,Architecture,Use MVVM with ReactiveUI or CommunityToolkit,Proven MVVM frameworks for Avalonia,ReactiveUI or CommunityToolkit.Mvvm for ViewModels,Code-behind for all logic,public class MainViewModel : ReactiveObject { },MainWindow.axaml.cs with all business logic,High,https://docs.avaloniaui.net/docs/how-to/mvvm-how-to,avalonia 12,active,2026-08-13
27,Architecture,Use ViewLocator pattern,Convention-based View-ViewModel resolution,ViewLocator for automatic view resolution,Manual view instantiation and DataContext wiring,class ViewLocator : IDataTemplate { Build(object data) => new MainView(); },new MainView { DataContext = new MainViewModel() } everywhere,Medium,https://docs.avaloniaui.net/docs/data-templates/view-locator,avalonia 12,active,2026-08-13
28,Architecture,Use dependency injection,Register services in a Microsoft.Extensions.DependencyInjection container during startup before any view is constructed - resolve ViewModels through the provider not via a static ServiceLocator,Build the ServiceProvider in BuildAvaloniaApp or OnFrameworkInitializationCompleted then resolve ViewModels from it,Static ServiceLocator or new-ing ViewModels inline in code-behind,"services.AddSingleton<IDataService, DataService>(); services.AddTransient<MainViewModel>(); var provider = services.BuildServiceProvider(); // wired before windows are created",ServiceLocator.Current.GetInstance<IDataService>() called from random ViewModels with no registration ordering,Medium,https://docs.avaloniaui.net/docs/app-development/dependency-injection,avalonia 12,active,2026-08-13
29,Architecture,Separate Views from ViewModels,Keep UI and logic in separate projects,ViewModels in a separate class library,ViewModels in the same project referencing Avalonia types,MyApp.Core (no Avalonia refs) + MyApp.Desktop (Avalonia views),ViewModel importing Avalonia.Controls,Medium,https://docs.avaloniaui.net/docs/how-to/mvvm-how-to,avalonia 12,active,2026-08-13
30,Accessibility,Set AutomationProperties,Enable screen reader support,AutomationProperties.Name on interactive controls,Controls without accessible names,"<Button AutomationProperties.Name=""Close dialog""><PathIcon Data=""...""/></Button>",<Button><PathIcon/></Button> without accessible name,High,https://docs.avaloniaui.net/api/avalonia/automation/automationproperties,avalonia 12,active,2026-08-13
31,Accessibility,Support keyboard navigation,Full keyboard operability,TabIndex and KeyboardNavigation properties,Mouse-only interactions,"<Button TabIndex=""1"" Content=""Save""/>",Clickable controls without keyboard support,High,https://docs.avaloniaui.net/docs/input-interaction/keyboard-and-hotkeys,avalonia 12,active,2026-08-13
32,Accessibility,Use semantic control types,Controls convey meaning to assistive tech,Button for actions ListBox for selection,TextBlock with PointerPressed as fake button,"<Button Content=""Submit""/>","<TextBlock PointerPressed=""OnSubmitClick"" Text=""Submit""/>",High,https://docs.avaloniaui.net/docs/reference/controls/,avalonia 12,active,2026-08-13
33,Testing,Use Avalonia.Headless for UI tests,Run UI tests without display server,Avalonia.Headless for CI-compatible UI testing,Skipping UI tests in CI,[AvaloniaTest] public void Button_Click_Updates_Label() { ... },UI tests that require a display server,Medium,https://docs.avaloniaui.net/docs/concepts/headless/,avalonia 12,active,2026-08-13
34,Testing,Unit test ViewModels,Test business logic independently,xUnit or NUnit on ViewModel methods,Testing through UI only,"[Fact] public void AddItem_IncreasesCount() { vm.AddItem(); Assert.Equal(1, vm.Items.Count); }",Manual testing by running the app,Medium,https://docs.avaloniaui.net/docs/concepts/headless/,avalonia 12,active,2026-08-13
35,Testing,Test converters independently,Value converters contain testable logic,Unit tests on Convert and ConvertBack,Assuming converters work without tests,"[Fact] public void BoolToColor_True_ReturnsGreen() { Assert.Equal(Brushes.Green, converter.Convert(true)); }",No converter tests,Low,https://docs.avaloniaui.net/docs/data-binding/how-to-create-a-custom-data-binding-converter,avalonia 12,active,2026-08-13
36,Navigation,Use ReactiveUI routing for navigation,IScreen and RoutingState for page navigation,ReactiveUI RoutingState with IScreen on main ViewModel,Manual content swapping in code-behind,public RoutingState Router { get; } = new(); Router.Navigate.Execute(new DetailViewModel());,contentControl.Content = new DetailView(); in code-behind,Medium,https://docs.avaloniaui.net/docs/how-to/navigation-how-to,avalonia 12,active,2026-08-13
37,Navigation,Use UserControl for views,Pages and screens should be UserControls hosted in a ContentControl,UserControl for each view with RoutedViewHost or ContentControl,Window per page or nested Windows,"<UserControl x:Class=""MyApp.Views.DetailView"">",new Window() for each page in the app,Medium,https://docs.avaloniaui.net/docs/custom-controls/,avalonia 12,active,2026-08-13
38,Navigation,Use page transitions for view switching,Built-in transitions for smooth navigation,CrossFade PageSlide or CompositePageTransition declared as a property element,Abrupt content swaps with no visual continuity,"<RoutedViewHost><RoutedViewHost.PageTransition><PageSlide Orientation=""Horizontal"" Duration=""0:0:0.3""/></RoutedViewHost.PageTransition></RoutedViewHost>",ContentControl with no transition between views,Low,https://docs.avaloniaui.net/docs/reference/controls/transitioningcontentcontrol,avalonia 12,active,2026-08-13
39,Navigation,Support back navigation,Maintain navigation history for complex apps,Router.NavigateBack or custom back stack,No way to return to previous views,"<Button Command=""{Binding Router.NavigateBack}"" Content=""Back""/>",Single-direction navigation with no back support,Medium,https://docs.avaloniaui.net/docs/how-to/navigation-how-to,avalonia 12,active,2026-08-13
40,Controls,Use AutoCompleteBox for search,Built-in autocomplete and suggestion control,AutoCompleteBox with FilterMode and ItemsSource,TextBox with manual Popup and ListBox for suggestions,"<AutoCompleteBox ItemsSource=""{Binding Suggestions}"" FilterMode=""Contains""/>",TextBox with custom Popup for autocomplete,Medium,https://docs.avaloniaui.net/docs/reference/controls/autocompletebox,avalonia 12,active,2026-08-13
41,Controls,Use TabControl for tabbed interfaces,Standard tabbed navigation and content switching,TabControl with TabItem for tabbed layouts,Manual toggle buttons swapping content,"<TabControl><TabItem Header=""General""><GeneralView/></TabItem><TabItem Header=""Advanced""><AdvancedView/></TabItem></TabControl>",ToggleButtons with manual content switching logic,Medium,https://docs.avaloniaui.net/docs/reference/controls/tabcontrol,avalonia 12,active,2026-08-13
42,Controls,Use SplitView for master-detail,Collapsible pane layout for navigation or panels,SplitView with Pane and Content areas,Manual Grid with column toggling for sidebar,"<SplitView IsPaneOpen=""{Binding IsPaneOpen}"" DisplayMode=""Inline""><SplitView.Pane><ListBox/></SplitView.Pane><ContentControl/></SplitView>",Grid with manual column width animation for sidebar,Medium,https://docs.avaloniaui.net/docs/reference/controls/splitview,avalonia 12,active,2026-08-13
43,Controls,Use Flyout for contextual actions,Attach popup menus and actions to controls,Flyout and MenuFlyout on Button or other controls,Custom Popup positioning and management,"<Button Content=""Options""><Button.Flyout><MenuFlyout><MenuItem Header=""Edit""/><MenuItem Header=""Delete""/></MenuFlyout></Button.Flyout></Button>",Custom Popup with manual open/close and positioning,Medium,https://docs.avaloniaui.net/docs/reference/controls/flyouts,avalonia 12,active,2026-08-13
44,Lifecycle,Use AppBuilder for app configuration,Configure platform features and services at startup,AppBuilder with UsePlatformDetect and fluent API,Manual platform initialization,AppBuilder.Configure<App>().UsePlatformDetect().WithInterFont().StartWithClassicDesktopLifetime(args);,Manual platform-specific startup code per OS,High,https://docs.avaloniaui.net/docs/fundamentals/application-lifetimes,avalonia 12,active,2026-08-13
45,Lifecycle,Initialize MainWindow in OnFrameworkInitializationCompleted,Override OnFrameworkInitializationCompleted on App and check ApplicationLifetime - on desktop cast to IClassicDesktopStyleApplicationLifetime to set MainWindow and ShutdownMode; never create windows in the App constructor before the framework is ready,Override OnFrameworkInitializationCompleted and pattern-match on IClassicDesktopStyleApplicationLifetime for desktop-only setup,Creating windows in the App constructor or assuming the same lifetime type on every platform,public override void OnFrameworkInitializationCompleted() { if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop) { desktop.MainWindow = new MainWindow(); desktop.ShutdownMode = ShutdownMode.OnMainWindowClose; } base.OnFrameworkInitializationCompleted(); },public App() { new MainWindow().Show(); } // window created before framework init and ignores lifetime type,High,https://docs.avaloniaui.net/docs/fundamentals/application-lifetimes,avalonia 12,active,2026-08-13
46,Animation,Use CSS-like keyframe animations,Avalonia supports declarative animations in XAML and code,Animation with KeyFrame and Setter for property animations,Manual timer-based property updates,"<Border.Transitions><DoubleTransition Property=""Opacity"" Duration=""0:0:0.3""/></Border.Transitions>",DispatcherTimer ticking to update Opacity manually,Medium,https://docs.avaloniaui.net/docs/graphics-animation/animations,avalonia 12,active,2026-08-13
47,Animation,Use Transitions for implicit animations,Automatic animation when property values change,Transitions collection on controls for smooth changes,Instant property changes with no visual feedback,"<Button.Transitions><TransformOperationsTransition Property=""RenderTransform"" Duration=""0:0:0.2""/></Button.Transitions>",Direct property set with no transition,Low,https://docs.avaloniaui.net/docs/graphics-animation/control-transitions,avalonia 12,active,2026-08-13
48,Performance,Use compiled bindings and TrimmerRoots.xml for PublishAot,Avalonia 11+ supports Native AOT for self-contained desktop deployments; XAML reflection paths must use compiled bindings or be preserved via TrimmerRoots so trimming does not strip them,x:CompileBindings=True on every view plus TrimmerRoots.xml for runtime-resolved types,PublishAot with reflection-based {Binding} markup or trimming without checking warnings,"<UserControl x:CompileBindings=""True"" x:DataType=""vm:MainViewModel""/> with <PublishAot>true</PublishAot> and TrimmerRoots.xml listing reflected types",<PublishAot>true</PublishAot> with default <Binding> markup and no TrimmerRoots configuration,Medium,https://docs.avaloniaui.net/docs/deployment/native-aot,avalonia 12,active,2026-08-13
49,Threading,Marshal cross-thread work to the UI thread,Avalonia controls and bound properties are not thread-safe and touching them off the UI thread throws InvalidOperationException,Dispatcher.UIThread.Post or InvokeAsync to bounce work back to the UI thread,Direct property writes from Task.Run or background threads,"await Dispatcher.UIThread.InvokeAsync(() => Status = ""Done"");","Task.Run(() => { Status = ""Done""; }); // throws Call from invalid thread",High,https://docs.avaloniaui.net/docs/app-development/threading,avalonia 12,active,2026-08-13
50,Commands,Use AsyncRelayCommand or ReactiveCommand for async work,Async-aware commands disable themselves while running and surface CancellationToken so users cannot double-invoke a long operation,[RelayCommand] async Task method or ReactiveCommand.CreateFromTask,async void event handlers or fire-and-forget Task.Run from a click handler,[RelayCommand] private async Task LoadAsync(CancellationToken ct) { await _api.GetAsync(ct); },"private async void OnClick(object s, RoutedEventArgs e) { await LongOperation(); }",High,https://docs.avaloniaui.net/docs/input-interaction/commanding,avalonia 12,active,2026-08-13
51,Styling,Use DynamicResource for theme-aware brushes,ResourceDictionary.ThemeDictionaries entries must be looked up via DynamicResource - StaticResource resolves once at load and won't update when the active theme variant changes,DynamicResource for brushes and colors that follow the active theme variant,Hardcoded hex colors or StaticResource for values that should follow theme,"<Border Background=""{DynamicResource SystemControlBackgroundAccentBrush}""/>","<Border Background=""#FF0078D4""/> while the rest of the app honors light/dark variants",Medium,https://docs.avaloniaui.net/docs/app-development/resource-dictionary,avalonia 12,active,2026-08-13
52,Input,Use HotKey or KeyBinding for keyboard shortcuts,Built-in HotKey on ICommandSource and Window.KeyBindings handle modifier keys focus scoping and cross-platform Ctrl/Cmd mapping,HotKey on a command-bound control or KeyBinding on the Window,Manual KeyDown handlers checking Key and KeyModifiers,"<Button Command=""{Binding SaveCommand}"" HotKey=""Ctrl+S"" Content=""Save""/>",OnKeyDown checking e.Key == Key.S && e.KeyModifiers == KeyModifiers.Control,Medium,https://docs.avaloniaui.net/docs/input-interaction/mouse-and-keyboard-shortcuts,avalonia 12,active,2026-08-13
53,Windowing,Customize window chrome with ExtendClientAreaToDecorationsHint,Set ExtendClientAreaToDecorationsHint to extend content into the title bar area and tag a region with WindowDecorationProperties.ElementRole=TitleBar to keep native drag and maximize behavior,ExtendClientAreaToDecorationsHint plus a region tagged ElementRole=TitleBar,SystemDecorations=None with hand-rolled PointerPressed dragging in code-behind,"<Window ExtendClientAreaToDecorationsHint=""True""><Border WindowDecorationProperties.ElementRole=""TitleBar""/></Window>","<Window SystemDecorations=""None""> with manual BeginMoveDrag from code-behind",Medium,https://docs.avaloniaui.net/docs/app-development/window-management,avalonia 12,active,2026-08-13
54,Storage,Use TopLevel.StorageProvider for file pickers,The legacy OpenFileDialog/SaveFileDialog APIs are obsolete - use TopLevel.GetTopLevel(this).StorageProvider with OpenFilePickerAsync/SaveFilePickerAsync/OpenFolderPickerAsync which returns IStorageFile/IStorageFolder and works on desktop mobile and browser,TopLevel.StorageProvider with OpenFilePickerAsync and FilePickerOpenOptions,OpenFileDialog or SaveFileDialog from older Avalonia samples or copied from WPF,var top = TopLevel.GetTopLevel(this); var files = await top.StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions { AllowMultiple = false });,var dlg = new OpenFileDialog(); var paths = await dlg.ShowAsync(window); // obsolete API,High,https://docs.avaloniaui.net/docs/services/storage/storage-provider,avalonia 12,active,2026-08-13
55,Windowing,Use TrayIcon for system tray icon,TrayIcon shows a native system tray/notification-area icon with a NativeMenu - declare it via the Application.TrayIcon.Icons attached property in App.axaml; works on Windows macOS and most Linux desktops,TrayIcon with NativeMenu inside TrayIcon.Icons on the Application,Custom borderless window pretending to be a tray icon or per-platform native interop,"<TrayIcon.Icons><TrayIcons><TrayIcon Icon=""/Assets/tray.ico"" ToolTipText=""MyApp""><TrayIcon.Menu><NativeMenu><NativeMenuItem Header=""Show"" Command=""{Binding ShowCommand}""/></NativeMenu></TrayIcon.Menu></TrayIcon></TrayIcons></TrayIcon.Icons>",Hidden Window with custom shell-notification-area P/Invoke,Medium,https://docs.avaloniaui.net/docs/controls/tray-icon,avalonia 12,active,2026-08-13
56,Cross-Platform,Use OnPlatform and OnFormFactor markup for per-OS values,OnPlatform and OnFormFactor markup extensions resolve to a different value per OS or form factor at XAML load time and replace if-statements in code-behind for tweaks like fonts spacing or icon sizes,OnPlatform with Default Windows macOS Linux entries directly in the property setter,RuntimeInformation.IsOSPlatform branches in code-behind to set XAML properties,"<TextBlock FontFamily=""{OnPlatform Default='Inter', Windows='Segoe UI', macOS='SF Pro Text', Linux='Ubuntu'}""/>","if (OperatingSystem.IsWindows()) textBlock.FontFamily = new(""Segoe UI""); else if (OperatingSystem.IsMacOS()) ...",Medium,https://docs.avaloniaui.net/docs/platform-specific-guides/xaml,avalonia 12,active,2026-08-13