Merge branch 'master' into feature/flowDirectionImpl

samples/ControlCatalog/Pages/ButtonsPage.xaml

@@ -147,6 +147,35 @@
       </StackPanel>
     </Border>
 
+    <!-- DropDownButton -->
+    <Border Classes="header-border">
+      <StackPanel Orientation="Vertical"
+                  Spacing="4">
+        <TextBlock Text="DropDownButton"
+                   Classes="header" />
+        <TextBlock TextWrapping="Wrap">A button with an added drop-down chevron to visually indicate it has a flyout with additional actions.</TextBlock>
+      </StackPanel>
+    </Border>
+
+    <Border Classes="thin"
+            Padding="15">
+      <StackPanel Orientation="Vertical"
+                  Spacing="8">
+        <DropDownButton Flyout="{StaticResource SharedMenuFlyout}">
+          <TextBlock Text="Drop Down Button" />
+        </DropDownButton>
+        <DropDownButton Padding="0,0,8,0">
+          <Border Background="Teal"
+                  HorizontalAlignment="Stretch"
+                  VerticalAlignment="Stretch"
+                  Height="32"
+                  Width="32" />
+        </DropDownButton>
+        <DropDownButton IsEnabled="False">Disabled</DropDownButton>
+        <DropDownButton />
+      </StackPanel>
+    </Border>
+
     <!-- SplitButton -->
     <Border Classes="header-border">
       <StackPanel Orientation="Vertical"
@@ -169,7 +198,8 @@
           <TextBlock Text="Disabled" />
         </SplitButton>
         <SplitButton Flyout="{StaticResource SharedMenuFlyout}"
-                     Content="Re-themed">
+                     Content="Re-themed"
+                     Foreground="White">
           <SplitButton.Styles>
             <Style>
               <Style.Resources>

src/Avalonia.Controls/ApiCompatBaseline.txt

@@ -1,4 +1,6 @@
 Compat issues with assembly Avalonia.Controls:
+TypesMustExist : Type 'Avalonia.Controls.DropDown' does not exist in the implementation but it does exist in the contract.
+TypesMustExist : Type 'Avalonia.Controls.DropDownItem' does not exist in the implementation but it does exist in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public System.Boolean Avalonia.Controls.IMenuItem.StaysOpenOnClick' is present in the implementation but not in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public System.Boolean Avalonia.Controls.IMenuItem.StaysOpenOnClick.get()' is present in the implementation but not in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Controls.IMenuItem.StaysOpenOnClick.set(System.Boolean)' is present in the implementation but not in the contract.
@@ -87,4 +89,4 @@ InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Platfor
 MembersMustExist : Member 'public void Avalonia.Platform.IWindowImpl.Resize(Avalonia.Size)' does not exist in the implementation but it does exist in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public void Avalonia.Platform.IWindowImpl.Resize(Avalonia.Size, Avalonia.Platform.PlatformResizeReason)' is present in the implementation but not in the contract.
 InterfacesShouldHaveSameMembers : Interface member 'public Avalonia.Platform.ITrayIconImpl Avalonia.Platform.IWindowingPlatform.CreateTrayIcon()' is present in the implementation but not in the contract.
-Total Issues: 88
+Total Issues: 90

src/Avalonia.Controls/Button.cs

@@ -29,11 +29,14 @@ namespace Avalonia.Controls
     }
 
     /// <summary>
-    /// A button control.
+    /// A standard button control.
     /// </summary>
-    [PseudoClasses(":pressed")]
-    public class Button : ContentControl, ICommandSource
+    [PseudoClasses(pcFlyoutOpen, pcPressed)]
+    public class Button : ContentControl, ICommandSource, IClickableControl
     {
+        protected const string pcPressed    = ":pressed";
+        protected const string pcFlyoutOpen = ":flyout-open";
+
         /// <summary>
         /// Defines the <see cref="ClickMode"/> property.
         /// </summary>
@@ -92,6 +95,7 @@ namespace Avalonia.Controls
         private ICommand? _command;
         private bool _commandCanExecute = true;
         private KeyGesture? _hotkey;
+        private bool _isFlyoutOpen = false;
 
         /// <summary>
         /// Initializes static members of the <see cref="Button"/> class.
@@ -107,7 +111,6 @@ namespace Avalonia.Controls
         /// </summary>
         public Button()
         {
-            UpdatePseudoClasses(IsPressed);
         }
 
         /// <summary>
@@ -328,11 +331,30 @@ namespace Avalonia.Controls
             }
         }
 
+        /// <summary>
+        /// Opens the button's flyout.
+        /// </summary>
         protected virtual void OpenFlyout()
         {
             Flyout?.ShowAt(this);
         }
 
+        /// <summary>
+        /// Invoked when the button's flyout is opened.
+        /// </summary>
+        protected virtual void OnFlyoutOpened()
+        {
+            // Available for derived types
+        }
+
+        /// <summary>
+        /// Invoked when the button's flyout is closed.
+        /// </summary>
+        protected virtual void OnFlyoutClosed()
+        {
+            // Available for derived types
+        }
+
         /// <inheritdoc/>
         protected override void OnPointerPressed(PointerPressedEventArgs e)
         {
@@ -382,6 +404,14 @@ namespace Avalonia.Controls
             IsPressed = false;
         }
 
+        /// <inheritdoc/>
+        protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
+        {
+            UnregisterFlyoutEvents(Flyout);
+            RegisterFlyoutEvents(Flyout);
+            UpdatePseudoClasses();
+        }
+
         /// <inheritdoc/>
         protected override void OnPropertyChanged<T>(AvaloniaPropertyChangedEventArgs<T> change)
         {
@@ -442,17 +472,26 @@ namespace Avalonia.Controls
             }
             else if (change.Property == IsPressedProperty)
             {
-                UpdatePseudoClasses(change.NewValue.GetValueOrDefault<bool>());
+                UpdatePseudoClasses();
             }
             else if (change.Property == FlyoutProperty)
             {
+                var oldFlyout = change.OldValue.GetValueOrDefault() as FlyoutBase;
+                var newFlyout = change.NewValue.GetValueOrDefault() as FlyoutBase;
+
                 // If flyout is changed while one is already open, make sure we 
                 // close the old one first
-                if (change.OldValue.GetValueOrDefault() is FlyoutBase oldFlyout &&
+                if (oldFlyout != null &&
                     oldFlyout.IsOpen)
                 {
                     oldFlyout.Hide();
                 }
+
+                // Must unregister events here while a reference to the old flyout still exists
+                UnregisterFlyoutEvents(oldFlyout);
+
+                RegisterFlyoutEvents(newFlyout);
+                UpdatePseudoClasses();
             }
         }
 
@@ -493,6 +532,32 @@ namespace Avalonia.Controls
             }
         }
 
+        /// <summary>
+        /// Registers all flyout events.
+        /// </summary>
+        /// <param name="flyout">The flyout to connect events to.</param>
+        private void RegisterFlyoutEvents(FlyoutBase? flyout)
+        {
+            if (flyout != null)
+            {
+                flyout.Opened += Flyout_Opened;
+                flyout.Closed += Flyout_Closed;
+            }
+        }
+
+        /// <summary>
+        /// Explicitly unregisters all flyout events.
+        /// </summary>
+        /// <param name="flyout">The flyout to disconnect events from.</param>
+        private void UnregisterFlyoutEvents(FlyoutBase? flyout)
+        {
+            if (flyout != null)
+            {
+                flyout.Opened -= Flyout_Opened;
+                flyout.Closed -= Flyout_Closed;
+             }
+        }
+
         /// <summary>
         /// Starts listening for the Enter key when the button <see cref="IsDefault"/>.
         /// </summary>
@@ -560,11 +625,53 @@ namespace Avalonia.Controls
         /// <summary>
         /// Updates the visual state of the control by applying latest PseudoClasses.
         /// </summary>
-        private void UpdatePseudoClasses(bool isPressed)
+        private void UpdatePseudoClasses()
         {
-            PseudoClasses.Set(":pressed", isPressed);
+            PseudoClasses.Set(pcFlyoutOpen, _isFlyoutOpen);
+            PseudoClasses.Set(pcPressed, IsPressed);
         }
 
         void ICommandSource.CanExecuteChanged(object sender, EventArgs e) => this.CanExecuteChanged(sender, e);
+
+        void IClickableControl.RaiseClick() => OnClick();
+        
+        /// <summary>
+        /// Event handler for when the button's flyout is opened.
+        /// </summary>
+        private void Flyout_Opened(object? sender, EventArgs e)
+        {
+            var flyout = sender as FlyoutBase;
+
+            // It is possible to share flyouts among multiple controls including Button.
+            // This can cause a problem here since all controls that share a flyout receive
+            // the same Opened/Closed events at the same time.
+            // For Button that means they all would be updating their pseudoclasses accordingly.
+            // In other words, all Buttons with a shared Flyout would have the backgrounds changed together.
+            // To fix this, only continue here if the Flyout target matches this Button instance.
+            if (object.ReferenceEquals(flyout?.Target, this))
+            {
+                _isFlyoutOpen = true;
+                UpdatePseudoClasses();
+
+                OnFlyoutOpened();
+            }
+        }
+
+        /// <summary>
+        /// Event handler for when the button's flyout is closed.
+        /// </summary>
+        private void Flyout_Closed(object? sender, EventArgs e)
+        {
+            var flyout = sender as FlyoutBase;
+
+            // See comments in Flyout_Opened
+            if (object.ReferenceEquals(flyout?.Target, this))
+            {
+                _isFlyoutOpen = false;
+                UpdatePseudoClasses();
+
+                OnFlyoutClosed();
+            }
+        }
     }
 }

src/Avalonia.Controls/DropDown.cs

@@ -1,28 +0,0 @@
-using System;
-using Avalonia.Logging;
-using Avalonia.Styling;
-
-namespace Avalonia.Controls
-{
-    [Obsolete("Use ComboBox")]
-    public class DropDown : ComboBox, IStyleable
-    {
-        public DropDown()
-        {
-            Logger.TryGet(LogEventLevel.Warning, LogArea.Control)?.Log(this, "DropDown is deprecated: Use ComboBox");
-        }
-
-        Type IStyleable.StyleKey => typeof(ComboBox);
-    }
-
-    [Obsolete("Use ComboBoxItem")]
-    public class DropDownItem : ComboBoxItem, IStyleable
-    {
-        public DropDownItem()
-        {
-            Logger.TryGet(LogEventLevel.Warning, LogArea.Control)?.Log(this, "DropDownItem is deprecated: Use ComboBoxItem");
-        }
-
-        Type IStyleable.StyleKey => typeof(ComboBoxItem);
-    }
-}

src/Avalonia.Controls/DropDownButton.cs

@@ -0,0 +1,15 @@
+namespace Avalonia.Controls
+{
+    /// <summary>
+    /// A button with an added drop-down chevron to visually indicate it has a flyout with additional actions.
+    /// </summary>
+    public class DropDownButton : Button
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="DropDownButton"/> class.
+        /// </summary>
+        public DropDownButton()
+        {
+        }
+    }
+}

src/Avalonia.Controls/HotkeyManager.cs

@@ -12,21 +12,61 @@ namespace Avalonia.Controls
 
         class HotkeyCommandWrapper : ICommand
         {
-            public HotkeyCommandWrapper(ICommandSource? control)
+            readonly WeakReference reference;
+
+            public HotkeyCommandWrapper(IControl control)
             {
-                CommandSource = control;
+                reference = new WeakReference(control);
             }
 
-            public readonly ICommandSource? CommandSource;
+            public ICommand? GetCommand()
+            {
+                if (reference.Target is { } target)
+                {
+                    if (target is ICommandSource commandSource && commandSource.Command is { } command)
+                    {
+                        return command;
+                    }
+                    else if (target is IClickableControl { })
+                    {
+                        return this;
+                    }
+                }
+                return null;
+            }
 
-            private ICommand? GetCommand() => CommandSource?.Command;
+            public bool CanExecute(object? parameter)
+            {
+                if (reference.Target is { } target)
+                {
+                    if (target is ICommandSource commandSource && commandSource.Command is { } command)
+                    {
+                        return commandSource.IsEffectivelyEnabled
+                            && command.CanExecute(commandSource.CommandParameter) == true;
+                    }
+                    else if (target is IClickableControl clickable)
+                    {
+                        return clickable.IsEffectivelyEnabled;
+                    }
+                }
+                return false;
+            }
 
-            public bool CanExecute(object? parameter) =>
-                CommandSource?.Command?.CanExecute(CommandSource.CommandParameter) == true
-                && CommandSource.IsEffectivelyEnabled;
+            public void Execute(object? parameter)
+            {
+                if (reference.Target is { } target)
+                {
+                    if (target is ICommandSource commandSource && commandSource.Command is { } command)
+                    {
+                        command.Execute(commandSource.CommandParameter);
+                    }
+                    else if (target is IClickableControl { IsEffectivelyEnabled: true } clickable)
+                    {
+                        clickable.RaiseClick();
+                    }
+                }
+            }
 
-            public void Execute(object? parameter) =>
-                GetCommand()?.Execute(CommandSource?.CommandParameter);
 
 #pragma warning disable 67 // Event not used
             public event EventHandler? CanExecuteChanged;
@@ -47,7 +87,7 @@ namespace Avalonia.Controls
             public Manager(IControl control)
             {
                 _control = control;
-                _wrapper = new HotkeyCommandWrapper(_control as ICommandSource);
+                _wrapper = new HotkeyCommandWrapper(_control);
             }
 
             public void Init()
@@ -104,13 +144,14 @@ namespace Avalonia.Controls
         {
             HotKeyProperty.Changed.Subscribe(args =>
             {
-                if (args.NewValue.Value is null) return;
+                if (args.NewValue.Value is null)
+                    return;
 
                 var control = args.Sender as IControl;
-                if (control is not ICommandSource)
+                if (control is not IClickableControl)
                 {
                     Logging.Logger.TryGet(Logging.LogEventLevel.Warning, Logging.LogArea.Control)?.Log(control,
-                        $"The element {args.Sender.GetType().Name} does not implement ICommandSource and does not support binding a HotKey ({args.NewValue}).");
+                        $"The element {args.Sender.GetType().Name} does not implement IClickableControl and does not support binding a HotKey ({args.NewValue}).");
                     return;
                 }
 

src/Avalonia.Controls/MenuItem.cs

@@ -22,7 +22,7 @@ namespace Avalonia.Controls
     /// </summary>
     [TemplatePart("PART_Popup", typeof(Popup))]
     [PseudoClasses(":separator", ":icon", ":open", ":pressed", ":selected")]
-    public class MenuItem : HeaderedSelectingItemsControl, IMenuItem, ISelectable, ICommandSource
+    public class MenuItem : HeaderedSelectingItemsControl, IMenuItem, ISelectable, ICommandSource, IClickableControl
     {
         /// <summary>
         /// Defines the <see cref="Command"/> property.
@@ -705,6 +705,14 @@ namespace Avalonia.Controls
 
         void ICommandSource.CanExecuteChanged(object sender, EventArgs e) => this.CanExecuteChanged(sender, e);
 
+        void IClickableControl.RaiseClick()
+        {
+            if (IsEffectivelyEnabled)
+            {
+                RaiseEvent(new RoutedEventArgs(ClickEvent));
+            }
+        }
+
         /// <summary>
         /// A dependency resolver which returns a <see cref="MenuItemAccessKeyHandler"/>.
         /// </summary>

src/Avalonia.Controls/Primitives/TemplatedControl.cs

@@ -356,6 +356,11 @@ namespace Avalonia.Controls.Primitives
             base.OnDetachedFromLogicalTree(e);
         }
 
+        /// <summary>
+        /// Called when the control's template is applied.
+        /// In simple terms, this means the method is called just before the control is displayed.
+        /// </summary>
+        /// <param name="e">The event args.</param>
         protected virtual void OnApplyTemplate(TemplateAppliedEventArgs e)
         {
         }

src/Avalonia.Controls/SplitButton/SplitButton.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Windows.Input;
 using Avalonia.Controls.Metadata;
-using Avalonia.Controls.Mixins;
 using Avalonia.Controls.Primitives;
 using Avalonia.Input;
 using Avalonia.Interactivity;
@@ -316,16 +315,9 @@ namespace Avalonia.Controls
                 }
 
                 // Must unregister events here while a reference to the old flyout still exists
-                if (oldFlyout != null)
-                {
-                    UnregisterFlyoutEvents(oldFlyout);
-                }
-
-                if (newFlyout != null)
-                {
-                    RegisterFlyoutEvents(newFlyout);
-                }
+                UnregisterFlyoutEvents(oldFlyout);
 
+                RegisterFlyoutEvents(newFlyout);
                 UpdatePseudoClasses();
             }
 
@@ -417,6 +409,22 @@ namespace Avalonia.Controls
             }
         }
 
+        /// <summary>
+        /// Invoked when the split button's flyout is opened.
+        /// </summary>
+        protected virtual void OnFlyoutOpened()
+        {
+            // Available for derived types
+        }
+
+        /// <summary>
+        /// Invoked when the split button's flyout is closed.
+        /// </summary>
+        protected virtual void OnFlyoutClosed()
+        {
+            // Available for derived types
+        }
+
         ////////////////////////////////////////////////////////////////////////
         // Event Handling
         ////////////////////////////////////////////////////////////////////////
@@ -466,6 +474,8 @@ namespace Avalonia.Controls
             {
                 _isFlyoutOpen = true;
                 UpdatePseudoClasses();
+
+                OnFlyoutOpened();
             }
         }
 
@@ -481,6 +491,8 @@ namespace Avalonia.Controls
             {
                 _isFlyoutOpen = false;
                 UpdatePseudoClasses();
+
+                OnFlyoutClosed();
             }
         }
     }

src/Avalonia.Input/IClickableControl.cs

@@ -0,0 +1,18 @@
+using System;
+using Avalonia.Interactivity;
+
+namespace Avalonia.Input
+{
+    /// <summary>
+    /// 
+    /// </summary>
+    internal interface IClickableControl
+    {
+        event EventHandler<RoutedEventArgs> Click;
+        void RaiseClick();
+        /// <summary>
+        /// Gets a value indicating whether this control and all its parents are enabled.
+        /// </summary>
+        bool IsEffectivelyEnabled { get; }
+    }
+}

src/Avalonia.Input/Properties/AssemblyInfo.cs

@@ -1,6 +1,10 @@
 using System.Reflection;
+using System.Runtime.CompilerServices;
 using Avalonia.Metadata;
 
 [assembly: XmlnsDefinition("https://github.com/avaloniaui", "Avalonia.Input")]
 [assembly: XmlnsDefinition("https://github.com/avaloniaui", "Avalonia.Input.TextInput")]
 [assembly: XmlnsDefinition("https://github.com/avaloniaui", "Avalonia.Input.GestureRecognizers")]
+
+[assembly: InternalsVisibleTo("Avalonia.Controls,  PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]
+[assembly: InternalsVisibleTo("Avalonia.Controls.UnitTests,  PublicKey=0024000004800000940000000602000000240000525341310004000001000100c1bba1142285fe0419326fb25866ba62c47e6c2b5c1ab0c95b46413fad375471232cb81706932e1cef38781b9ebd39d5100401bacb651c6c5bbf59e571e81b3bc08d2a622004e08b1a6ece82a7e0b9857525c86d2b95fab4bc3dce148558d7f3ae61aa3a234086902aeface87d9dfdd32b9d2fe3c6dd4055b5ab4b104998bd87")]

src/Avalonia.Themes.Default/Controls/DropDownButton.xaml

@@ -0,0 +1,67 @@
+<Styles xmlns="https://github.com/avaloniaui">
+  <Style Selector="DropDownButton">
+    <Setter Property="Background" Value="{DynamicResource ThemeControlMidBrush}"/>
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderLowBrush}"/>
+    <Setter Property="BorderThickness" Value="{DynamicResource ThemeBorderThickness}"/>
+    <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundBrush}"/>
+    <Setter Property="HorizontalContentAlignment" Value="Center"/>
+    <Setter Property="VerticalContentAlignment" Value="Center"/>
+    <Setter Property="Padding" Value="4"/>
+    <Setter Property="Template">
+      <Setter.Value>
+        <ControlTemplate>
+          <Border Name="RootBorder"
+                  Background="{TemplateBinding Background}"
+                  BorderBrush="{TemplateBinding BorderBrush}"
+                  BorderThickness="{TemplateBinding BorderThickness}"
+                  CornerRadius="{TemplateBinding CornerRadius}"
+                  ClipToBounds="True">
+            <Grid Name="InnerGrid">
+              <Grid.ColumnDefinitions>
+                <ColumnDefinition Width="*" />
+                <ColumnDefinition Width="Auto" />
+              </Grid.ColumnDefinitions>
+
+              <ContentPresenter Name="PART_ContentPresenter"
+                                Grid.Column="0"
+                                Content="{TemplateBinding Content}"
+                                ContentTemplate="{TemplateBinding ContentTemplate}"
+                                Padding="{TemplateBinding Padding}"
+                                RecognizesAccessKey="True"
+                                HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
+                                VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" />
+
+              <PathIcon Name="DropDownGlyph"
+                        Grid.Column="1"
+                        UseLayoutRounding="False"
+                        IsHitTestVisible="False"
+                        Height="12"
+                        Width="12"
+                        Margin="0,0,10,0"
+                        HorizontalAlignment="Right"
+                        VerticalAlignment="Center" />
+
+            </Grid>
+          </Border>
+        </ControlTemplate>
+      </Setter.Value>
+    </Setter>
+  </Style>
+
+  <Style Selector="DropDownButton /template/ PathIcon#DropDownGlyph">
+    <Setter Property="Foreground" Value="{DynamicResource ThemeForegroundBrush}" />
+    <Setter Property="Data" Value="M1939 486L2029 576L1024 1581L19 576L109 486L1024 1401L1939 486Z" />
+  </Style>
+
+  <Style Selector="DropDownButton:pointerover /template/ Border#RootBorder">
+    <Setter Property="BorderBrush" Value="{DynamicResource ThemeBorderMidBrush}"/>
+  </Style>
+
+  <Style Selector="DropDownButton:pressed  /template/ Border#RootBorder">
+    <Setter Property="Background" Value="{DynamicResource ThemeControlHighBrush}"/>
+  </Style>
+
+  <Style Selector="DropDownButton:disabled">
+    <Setter Property="Opacity" Value="{DynamicResource ThemeDisabledOpacity}"/>
+  </Style>
+</Styles>

src/Avalonia.Themes.Default/Controls/SplitButton.xaml

@@ -16,6 +16,7 @@
     <x:Double x:Key="SplitButtonPrimaryButtonSize">24</x:Double>
     <x:Double x:Key="SplitButtonSecondaryButtonSize">24</x:Double>
     <x:Double x:Key="SplitButtonSeparatorWidth">1</x:Double>
+    <x:Double x:Key="SplitButtonMinHeight">24</x:Double>
     <Thickness x:Key="SplitButtonBorderThemeThickness">1</Thickness>
 
     <converters:MarginMultiplierConverter x:Key="PrimaryButtonBorderMultiplier" Left="True" Top="True" Bottom="True" Indent="1" />
@@ -59,8 +60,11 @@
     <Setter Property="Foreground" Value="{DynamicResource SplitButtonForeground}" />
     <Setter Property="BorderBrush" Value="{DynamicResource SplitButtonBorderBrush}" />
     <Setter Property="BorderThickness" Value="{DynamicResource SplitButtonBorderThemeThickness}" />
+    <Setter Property="MinHeight" Value="{DynamicResource SplitButtonMinHeight}" />
     <Setter Property="HorizontalAlignment" Value="Left" />
     <Setter Property="VerticalAlignment" Value="Center" />
+    <Setter Property="HorizontalContentAlignment" Value="Stretch" />
+    <Setter Property="VerticalContentAlignment" Value="Center" />
     <!--<Setter Property="UseSystemFocusVisuals" Value="True" />
     <Setter Property="FocusVisualMargin" Value="-3" />-->
     <Setter Property="KeyboardNavigation.IsTabStop" Value="True" />

src/Avalonia.Themes.Default/DefaultTheme.xaml

@@ -14,6 +14,7 @@
   <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/ComboBox.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/ComboBoxItem.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/ContentControl.xaml"/>
+  <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/DropDownButton.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/Label.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/GridSplitter.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Default/Controls/ItemsControl.xaml"/>

src/Avalonia.Themes.Fluent/Controls/Button.xaml

@@ -4,7 +4,7 @@
       <StackPanel Spacing="20">
         <Button Content="Click Me!" />
         <Button Classes="accent" Content="Click Me!" />
-      </StackPanel>      
+      </StackPanel>
     </Border>
   </Design.PreviewWith>
   <Styles.Resources>
@@ -19,9 +19,7 @@
     <Setter Property="CornerRadius" Value="{DynamicResource ControlCornerRadius}" />
     <Setter Property="Padding" Value="{DynamicResource ButtonPadding}" />
     <Setter Property="HorizontalAlignment" Value="Left" />
-    <Setter Property="VerticalAlignment" Value="Center" />    
-    <Setter Property="FontWeight" Value="Normal" />
-    <Setter Property="FontSize" Value="{DynamicResource ControlContentThemeFontSize}" />
+    <Setter Property="VerticalAlignment" Value="Center" />
     <!--<Setter Property="UseSystemFocusVisuals" Value="{StaticResource UseSystemFocusVisuals}" />
     <Setter Property="FocusVisualMargin" Value="-3" />-->
     <Setter Property="Template">
@@ -47,13 +45,13 @@
     <Setter Property="BorderBrush" Value="{DynamicResource ButtonBorderBrushPointerOver}" />
     <Setter Property="TextElement.Foreground" Value="{DynamicResource ButtonForegroundPointerOver}" />
   </Style>
-  
+
   <Style Selector="Button:pressed  /template/ ContentPresenter#PART_ContentPresenter">
     <Setter Property="Background" Value="{DynamicResource ButtonBackgroundPressed}" />
     <Setter Property="BorderBrush" Value="{DynamicResource ButtonBorderBrushPressed}" />
     <Setter Property="TextElement.Foreground" Value="{DynamicResource ButtonForegroundPressed}" />
   </Style>
-  
+
   <Style Selector="Button:disabled /template/ ContentPresenter#PART_ContentPresenter">
     <Setter Property="Background" Value="{DynamicResource ButtonBackgroundDisabled}" />
     <Setter Property="BorderBrush" Value="{DynamicResource ButtonBorderBrushDisabled}" />
@@ -78,7 +76,7 @@
     <Setter Property="TextElement.Foreground" Value="{DynamicResource AccentButtonForegroundPressed}" />
   </Style>
 
-  <Style Selector="Button, RepeatButton, ToggleButton">
+  <Style Selector="Button, RepeatButton, ToggleButton, DropDownButton">
     <Setter Property="RenderTransform" Value="none" />
     <Setter Property="Transitions">
       <Transitions>
@@ -87,7 +85,7 @@
     </Setter>
   </Style>
 
-  <Style Selector="Button:pressed, RepeatButton:pressed, ToggleButton:pressed">
+  <Style Selector="Button:pressed, RepeatButton:pressed, ToggleButton:pressed, DropDownButton:pressed">
     <Setter Property="RenderTransform" Value="scale(0.98)" />    
   </Style>
 

src/Avalonia.Themes.Fluent/Controls/ComboBox.xaml

@@ -37,6 +37,7 @@
     <Setter Property="CornerRadius" Value="{DynamicResource ControlCornerRadius}" />
     <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled" />
     <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto" />
+    <Setter Property="MinHeight" Value="{DynamicResource ComboBoxMinHeight}" />
     <Setter Property="HorizontalContentAlignment" Value="Stretch" />
     <Setter Property="VerticalContentAlignment" Value="Center" />
     <Setter Property="HorizontalAlignment" Value="Left" />

src/Avalonia.Themes.Fluent/Controls/DropDownButton.xaml

@@ -0,0 +1,103 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        x:CompileBindings="True">
+
+  <Design.PreviewWith>
+    <Border Padding="20">
+      <StackPanel Spacing="20">
+        <DropDownButton Content="Click Me!" />
+        <DropDownButton Content="Disabled" IsEnabled="False" />
+      </StackPanel>
+    </Border>
+  </Design.PreviewWith>
+
+  <Styles.Resources>
+    <x:Double x:Key="DropDownButtonMinHeight">32</x:Double>
+  </Styles.Resources>
+  
+  <Style Selector="DropDownButton">
+    <Setter Property="Background" Value="{DynamicResource ButtonBackground}" />
+    <Setter Property="Foreground" Value="{DynamicResource ButtonForeground}" />
+    <Setter Property="BorderBrush" Value="{DynamicResource ButtonBorderBrush}" />
+    <Setter Property="BorderThickness" Value="{DynamicResource ButtonBorderThemeThickness}" />
+    <Setter Property="Padding" Value="{DynamicResource ButtonPadding}" />
+    <Setter Property="MinHeight" Value="{DynamicResource DropDownButtonMinHeight}" />
+    <Setter Property="HorizontalAlignment" Value="Left" />
+    <Setter Property="VerticalAlignment" Value="Center" />
+    <Setter Property="HorizontalContentAlignment" Value="Stretch" />
+    <Setter Property="VerticalContentAlignment" Value="Center" />
+    <!--<Setter Property="UseSystemFocusVisuals" Value="{StaticResource UseSystemFocusVisuals}" />
+    <Setter Property="FocusVisualMargin" Value="-3" />-->
+    <Setter Property="CornerRadius" Value="{DynamicResource ControlCornerRadius}" />
+    <Setter Property="Template">
+      <Setter.Value>
+        <ControlTemplate>
+          <Border x:Name="RootBorder"
+                  Background="{TemplateBinding Background}"
+                  BorderBrush="{TemplateBinding BorderBrush}"
+                  BorderThickness="{TemplateBinding BorderThickness}"
+                  CornerRadius="{TemplateBinding CornerRadius}"
+                  ClipToBounds="True">
+            <Grid x:Name="InnerGrid">
+              <Grid.ColumnDefinitions>
+                <ColumnDefinition Width="*" />
+                <ColumnDefinition Width="Auto" />
+              </Grid.ColumnDefinitions>
+
+              <ContentPresenter x:Name="PART_ContentPresenter"
+                                Grid.Column="0"
+                                Content="{TemplateBinding Content}"
+                                ContentTemplate="{TemplateBinding ContentTemplate}"
+                                Padding="{TemplateBinding Padding}"
+                                RecognizesAccessKey="True"
+                                HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
+                                VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" />
+
+              <PathIcon x:Name="DropDownGlyph"
+                        Grid.Column="1"
+                        UseLayoutRounding="False"
+                        IsHitTestVisible="False"
+                        Height="12"
+                        Width="12"
+                        Margin="0,0,10,0"
+                        HorizontalAlignment="Right"
+                        VerticalAlignment="Center" />
+
+            </Grid>
+          </Border>
+        </ControlTemplate>
+      </Setter.Value>
+    </Setter>
+  </Style>
+
+  <!--  Normal State  -->
+  <Style Selector="DropDownButton /template/ PathIcon#DropDownGlyph">
+    <Setter Property="Foreground" Value="{DynamicResource ComboBoxDropDownGlyphForeground}" />
+    <Setter Property="Data" Value="M1939 486L2029 576L1024 1581L19 576L109 486L1024 1401L1939 486Z" />
+  </Style>
+
+  <!--  PointerOver State  -->
+  <Style Selector="DropDownButton:pointerover /template/ Border#RootBorder">
+    <Setter Property="Background" Value="{DynamicResource ButtonBackgroundPointerOver}" />
+    <Setter Property="BorderBrush" Value="{DynamicResource ButtonBorderBrushPointerOver}" />
+    <Setter Property="TextElement.Foreground" Value="{DynamicResource ButtonForegroundPointerOver}" />
+  </Style>
+
+  <!--  Pressed State  -->
+  <Style Selector="DropDownButton:pressed  /template/ Border#RootBorder">
+    <Setter Property="Background" Value="{DynamicResource ButtonBackgroundPressed}" />
+    <Setter Property="BorderBrush" Value="{DynamicResource ButtonBorderBrushPressed}" />
+    <Setter Property="TextElement.Foreground" Value="{DynamicResource ButtonForegroundPressed}" />
+  </Style>
+
+  <!--  Disabled State  -->
+  <Style Selector="DropDownButton:disabled /template/ Border#RootBorder">
+    <Setter Property="Background" Value="{DynamicResource ButtonBackgroundDisabled}" />
+    <Setter Property="BorderBrush" Value="{DynamicResource ButtonBorderBrushDisabled}" />
+    <Setter Property="TextElement.Foreground" Value="{DynamicResource ButtonForegroundDisabled}" />
+  </Style>
+  <Style Selector="DropDownButton:disabled /template/ PathIcon#DropDownGlyph">
+    <Setter Property="Foreground" Value="{DynamicResource ButtonForegroundDisabled}" />
+  </Style>
+
+</Styles>

src/Avalonia.Themes.Fluent/Controls/FluentControls.xaml

@@ -14,6 +14,7 @@
   <StyleInclude Source="avares://Avalonia.Themes.Fluent/Controls/ComboBox.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Fluent/Controls/ComboBoxItem.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Fluent/Controls/ContentControl.xaml"/>
+  <StyleInclude Source="avares://Avalonia.Themes.Fluent/Controls/DropDownButton.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Fluent/Controls/Label.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Fluent/Controls/GridSplitter.xaml"/>
   <StyleInclude Source="avares://Avalonia.Themes.Fluent/Controls/ItemsControl.xaml"/>

src/Avalonia.Themes.Fluent/Controls/SplitButton.xaml

@@ -24,6 +24,7 @@
     <x:Double x:Key="SplitButtonPrimaryButtonSize">32</x:Double>
     <x:Double x:Key="SplitButtonSecondaryButtonSize">32</x:Double>
     <x:Double x:Key="SplitButtonSeparatorWidth">1</x:Double>
+    <x:Double x:Key="SplitButtonMinHeight">32</x:Double>
 
     <converters:MarginMultiplierConverter x:Key="PrimaryButtonBorderMultiplier" Left="True" Top="True" Bottom="True" Indent="1" />
     <converters:MarginMultiplierConverter x:Key="SecondaryButtonBorderMultiplier" Right="True" Top="True" Bottom="True" Indent="1" />
@@ -35,8 +36,11 @@
     <Setter Property="Foreground" Value="{DynamicResource SplitButtonForeground}" />
     <Setter Property="BorderBrush" Value="{DynamicResource SplitButtonBorderBrush}" />
     <Setter Property="BorderThickness" Value="{DynamicResource SplitButtonBorderThemeThickness}" />
+    <Setter Property="MinHeight" Value="{DynamicResource SplitButtonMinHeight}" />
     <Setter Property="HorizontalAlignment" Value="Left" />
     <Setter Property="VerticalAlignment" Value="Center" />
+    <Setter Property="HorizontalContentAlignment" Value="Stretch" />
+    <Setter Property="VerticalContentAlignment" Value="Center" />
     <!--<Setter Property="UseSystemFocusVisuals" Value="True" />
     <Setter Property="FocusVisualMargin" Value="-3" />-->
     <Setter Property="KeyboardNavigation.IsTabStop" Value="True" />

tests/Avalonia.Controls.UnitTests/Utils/HotKeyManagerTests.cs

@@ -170,7 +170,7 @@ namespace Avalonia.Controls.UnitTests.Utils
         }
 
         [Theory]
-        [MemberData(nameof(ElementsFactory))]
+        [MemberData(nameof(ElementsFactory), parameters: true)]
         public void HotKeyManager_Should_Use_CommandParameter(string factoryName, Factory factory)
         {
             using (AvaloniaLocator.EnterScope())
@@ -215,7 +215,7 @@ namespace Avalonia.Controls.UnitTests.Utils
 
 
         [Theory]
-        [MemberData(nameof(ElementsFactory))]
+        [MemberData(nameof(ElementsFactory), parameters: true)]
         public void HotKeyManager_Should_Do_Not_Executed_When_IsEnabled_False(string factoryName, Factory factory)
         {
             using (AvaloniaLocator.EnterScope())
@@ -256,11 +256,127 @@ namespace Avalonia.Controls.UnitTests.Utils
             }
         }
 
-        public static TheoryData<string, Factory> ElementsFactory =>
+        [Theory]
+        [MemberData(nameof(ElementsFactory), parameters:false)]
+        public void HotKeyManager_Should_Invoke_Event_Click_When_Command_Is_Null(string factoryName, Factory factory)
+        {
+            using (AvaloniaLocator.EnterScope())
+            {
+                var styler = new Mock<Styler>();
+                var target = new KeyboardDevice();
+                var clickExecutedCount = 0;
+                AvaloniaLocator.CurrentMutable
+                    .Bind<IWindowingPlatform>().ToConstant(new WindowingPlatformMock())
+                    .Bind<IStyler>().ToConstant(styler.Object);
+
+                var gesture = new KeyGesture(Key.A, KeyModifiers.Control);
+
+                void Clickable_Click(object sender, Interactivity.RoutedEventArgs e)
+                {
+                    clickExecutedCount++;
+                }
+
+                var root = new Window();
+                var element = factory(0, default, root) as InputElement;
+                if (element is IClickableControl clickable)
+                {
+                    clickable.Click += Clickable_Click;
+                }
+
+                root.Template = CreateWindowTemplate();
+                root.ApplyTemplate();
+                root.Presenter.ApplyTemplate();
+
+                HotKeyManager.SetHotKey(element, gesture);
+
+                target.ProcessRawEvent(new RawKeyEventArgs(target,
+                    0,
+                    root,
+                    RawKeyEventType.KeyDown,
+                    Key.A,
+                    RawInputModifiers.Control));
+
+                element.IsEnabled = false;
+
+                target.ProcessRawEvent(new RawKeyEventArgs(target,
+                    0,
+                    root,
+                    RawKeyEventType.KeyDown,
+                    Key.A,
+                    RawInputModifiers.Control));
+
+
+                Assert.True(clickExecutedCount == 1, $"{factoryName} Execution raised when IsEnabled is false.");
+            }
+        }
+
+        [Theory]
+        [MemberData(nameof(ElementsFactory), parameters: true)]
+        public void HotKeyManager_Should_Not_Invoke_Event_Click_When_Command_Is_Not_Null(string factoryName, Factory factory)
+        {
+            using (AvaloniaLocator.EnterScope())
+            {
+                var styler = new Mock<Styler>();
+                var target = new KeyboardDevice();
+                var clickExecutedCount = 0;
+                var commandExecutedCount = 0;
+                AvaloniaLocator.CurrentMutable
+                    .Bind<IWindowingPlatform>().ToConstant(new WindowingPlatformMock())
+                    .Bind<IStyler>().ToConstant(styler.Object);
+
+                var gesture = new KeyGesture(Key.A, KeyModifiers.Control);
+
+                void DoExecute(object parameter)
+                {
+                    commandExecutedCount++;
+                }
+
+                void Clickable_Click(object sender, Interactivity.RoutedEventArgs e)
+                {
+                    clickExecutedCount++;
+                }
+
+                var root = new Window();
+                var element = factory(0, DoExecute, root) as InputElement;
+                if (element is IClickableControl clickable)
+                {
+                    clickable.Click += Clickable_Click;
+                }
+
+                root.Template = CreateWindowTemplate();
+                root.ApplyTemplate();
+                root.Presenter.ApplyTemplate();
+
+                HotKeyManager.SetHotKey(element, gesture);
+
+                target.ProcessRawEvent(new RawKeyEventArgs(target,
+                    0,
+                    root,
+                    RawKeyEventType.KeyDown,
+                    Key.A,
+                    RawInputModifiers.Control));
+
+                element.IsEnabled = false;
+
+                target.ProcessRawEvent(new RawKeyEventArgs(target,
+                    0,
+                    root,
+                    RawKeyEventType.KeyDown,
+                    Key.A,
+                    RawInputModifiers.Control));
+
+                Assert.True(commandExecutedCount == 1, $"{factoryName} Execution raised when IsEnabled is false.");
+                Assert.True(clickExecutedCount == 0, $"{factoryName} Execution raised event Click.");
+            }
+        }
+
+
+        public static TheoryData<string, Factory> ElementsFactory(bool withCommand) =>
+
             new TheoryData<string, Factory>()
             {
-                {nameof(Button), MakeButton},
-                {nameof(MenuItem),MakeMenu},
+                {nameof(Button), withCommand ? MakeButton : MakeButtonWithoutCommand},
+                {nameof(MenuItem),withCommand ? MakeMenu : MakeMenuWithoutCommand},
             };
 
         private static AvaloniaObject MakeMenu(int expectedParameter, Action<object> action, Window root)
@@ -290,6 +406,29 @@ namespace Avalonia.Controls.UnitTests.Utils
             return button;
         }
 
+        private static AvaloniaObject MakeMenuWithoutCommand(int expectedParameter, Action<object> action, Window root)
+        {
+            var menuitem = new MenuItem()
+            {
+            };
+            var rootMenu = new Menu();
+
+            rootMenu.Items = new[] { menuitem };
+
+            root.Content = rootMenu;
+            return menuitem;
+        }
+
+        private static AvaloniaObject MakeButtonWithoutCommand(int expectedParameter, Action<object> action, Window root)
+        {
+            var button = new Button()
+            {
+            };
+
+            root.Content = button;
+            return button;
+        }
+
         private FuncControlTemplate CreateWindowTemplate()
         {
             return new FuncControlTemplate<Window>((parent, scope) =>