feat: add basic implementation of window decorations.

demo/Directory.Packages.props

@@ -1,7 +1,7 @@
 <Project>
     <PropertyGroup>
         <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
-        <AvaloniaVersion>12.0.0-preview1</AvaloniaVersion>
+        <AvaloniaVersion>12.0.0-preview2</AvaloniaVersion>
         <DataGridVersion>11.3.10</DataGridVersion>
         <SkiaSharpVersion>3.119.1</SkiaSharpVersion>
     </PropertyGroup>

demo/Semi.Avalonia.Demo/Views/MainWindow.axaml

@@ -5,10 +5,12 @@
     xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
     xmlns:views="clr-namespace:Semi.Avalonia.Demo.Views"
-    Title="Semi.Avalonia.Demo"
+    Title="Semi Avalonia Demo"
     d:DesignHeight="450"
     d:DesignWidth="800"
+    ExtendClientAreaToDecorationsHint="True"
+    ExtendClientAreaTitleBarHeightHint="40"
     Icon="/Assets/irihi.ico"
     mc:Ignorable="d">
-    <views:MainView />
+    <views:MainView Margin="{Binding $parent[Window].WindowDecorationMargin}" />
 </Window>

src/Directory.Packages.props

@@ -1,7 +1,7 @@
 <Project>
     <PropertyGroup>
         <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
-        <AvaloniaVersion>12.0.0-preview1</AvaloniaVersion>
+        <AvaloniaVersion>12.0.0-preview2</AvaloniaVersion>
         <DataGridVersion>11.3.7</DataGridVersion>
     </PropertyGroup>
     <ItemGroup>

src/Semi.Avalonia.ColorPicker/SemiColorDarkPalette.cs

@@ -1,6 +1,7 @@
 using Avalonia.Controls;
 using Avalonia.Media;
 using Avalonia.Utilities;
+using Irihi.Avalonia.Shared.Helpers;
 
 namespace Semi.Avalonia.ColorPicker;
 
@@ -220,8 +221,8 @@ public class SemiColorDarkPalette: IColorPalette
     public Color GetColor(int colorIndex, int shadeIndex)
     {
         return Colors[
-            MathUtilities.Clamp(colorIndex, 0, ColorCount - 1),
-            MathUtilities.Clamp(shadeIndex, 0, ShadeCount - 1)
+            MathHelpers.SafeClamp(colorIndex, 0, ColorCount - 1),
+            MathHelpers.SafeClamp(shadeIndex, 0, ShadeCount - 1)
         ];
     }
 

src/Semi.Avalonia.ColorPicker/SemiColorLightPalette.cs

@@ -1,6 +1,7 @@
 using Avalonia.Controls;
 using Avalonia.Media;
 using Avalonia.Utilities;
+using Irihi.Avalonia.Shared.Helpers;
 
 namespace Semi.Avalonia.ColorPicker;
 
@@ -220,8 +221,8 @@ public class SemiColorLightPalette: IColorPalette
     public Color GetColor(int colorIndex, int shadeIndex)
     {
         return Colors[
-            MathUtilities.Clamp(colorIndex, 0, ColorCount - 1),
-            MathUtilities.Clamp(shadeIndex, 0, ShadeCount - 1)
+            MathHelpers.SafeClamp(colorIndex, 0, ColorCount - 1),
+            MathHelpers.SafeClamp(shadeIndex, 0, ShadeCount - 1)
         ];
     }
 

src/Semi.Avalonia/Controls/CaptionButtons.axaml

@@ -1,112 +0,0 @@
-<ResourceDictionary
-    xmlns="https://github.com/avaloniaui"
-    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
-    <Design.PreviewWith>
-        <CaptionButtons />
-    </Design.PreviewWith>
-
-    <ControlTheme x:Key="CaptionButton" TargetType="Button">
-        <Setter Property="Foreground" Value="{DynamicResource CaptionButtonForeground}" />
-        <Setter Property="Background" Value="Transparent" />
-        <Setter Property="CornerRadius" Value="{StaticResource CaptionButtonCornerRadius}" />
-        <Setter Property="Padding" Value="{StaticResource CaptionButtonPadding}" />
-        <Setter Property="Width" Value="{StaticResource CaptionButtonWidth}" />
-        <Setter Property="Height" Value="{StaticResource CaptionButtonHeight}" />
-        <Setter Property="Cursor" Value="Hand" />
-        <Setter Property="VerticalAlignment" Value="Stretch" />
-        <Setter Property="Template">
-            <ControlTemplate TargetType="Button">
-                <ContentPresenter
-                    Name="PART_ContentPresenter"
-                    Padding="{TemplateBinding Padding}"
-                    Foreground="{TemplateBinding Foreground}"
-                    Background="{TemplateBinding Background}"
-                    BorderBrush="{TemplateBinding BorderBrush}"
-                    BorderThickness="{TemplateBinding BorderThickness}"
-                    Content="{TemplateBinding Content}"
-                    ContentTemplate="{TemplateBinding ContentTemplate}"
-                    CornerRadius="{TemplateBinding CornerRadius}" />
-            </ControlTemplate>
-        </Setter>
-
-        <Style Selector="^:pointerover">
-            <Setter Property="Background" Value="{DynamicResource CaptionButtonPointeroverBackground}" />
-        </Style>
-
-        <Style Selector="^:pressed">
-            <Setter Property="Background" Value="{DynamicResource CaptionButtonPressedBackground}" />
-        </Style>
-    </ControlTheme>
-
-    <ControlTheme x:Key="{x:Type CaptionButtons}" TargetType="CaptionButtons">
-        <Setter Property="Foreground" Value="{DynamicResource CaptionButtonForeground}" />
-        <Setter Property="Template">
-            <ControlTemplate TargetType="CaptionButtons">
-                <StackPanel Orientation="Horizontal">
-                    <Button Name="PART_FullScreenButton" Theme="{StaticResource CaptionButton}">
-                        <PathIcon
-                            Name="PART_FullScreenButtonIcon"
-                            Theme="{StaticResource InnerPathIcon}"
-                            Data="{StaticResource WindowExpandGlyph}"
-                            Foreground="{Binding $parent[Button].Foreground}" />
-                    </Button>
-                    <Button
-                        Name="PART_MinimizeButton"
-                        Theme="{StaticResource CaptionButton}"
-                        AutomationProperties.Name="Minimize"
-                        Win32Properties.NonClientHitTestResult="MinButton">
-                        <PathIcon
-                            Name="PART_MinimizeButtonIcon"
-                            Theme="{StaticResource InnerPathIcon}"
-                            Data="{StaticResource WindowMinimizeGlyph}"
-                            Foreground="{Binding $parent[Button].Foreground}" />
-                    </Button>
-                    <Button
-                        Name="PART_RestoreButton"
-                        Theme="{StaticResource CaptionButton}"
-                        AutomationProperties.Name="Maximize"
-                        Win32Properties.NonClientHitTestResult="MaxButton">
-                        <PathIcon
-                            Name="PART_RestoreButtonIcon"
-                            Theme="{StaticResource InnerPathIcon}"
-                            Data="{StaticResource WindowMaximizeGlyph}"
-                            Foreground="{Binding $parent[Button].Foreground}" />
-                    </Button>
-                    <Button
-                        Name="PART_CloseButton"
-                        Theme="{StaticResource CaptionButton}"
-                        AutomationProperties.Name="Close"
-                        Win32Properties.NonClientHitTestResult="Close">
-                        <PathIcon
-                            Name="PART_CloseButtonIcon"
-                            Theme="{StaticResource InnerPathIcon}"
-                            Data="{StaticResource WindowCloseIconGlyph}"
-                            Foreground="{Binding $parent[Button].Foreground}" />
-                    </Button>
-                </StackPanel>
-            </ControlTemplate>
-        </Setter>
-
-        <Style Selector="^ /template/ Button#PART_CloseButton:pointerover">
-            <Setter Property="Foreground" Value="{DynamicResource CaptionButtonCloseForeground}" />
-            <Setter Property="Background" Value="{DynamicResource CaptionButtonClosePointeroverBackground}" />
-        </Style>
-        <Style Selector="^ /template/ Button#PART_CloseButton:pressed">
-            <Setter Property="Foreground" Value="{DynamicResource CaptionButtonCloseForeground}" />
-            <Setter Property="Background" Value="{DynamicResource CaptionButtonClosePressedBackground}" />
-        </Style>
-
-        <Style Selector="^:maximized /template/ PathIcon#PART_RestoreButtonIcon">
-            <Setter Property="Data" Value="{StaticResource WindowRestoreGlyph}" />
-        </Style>
-        <Style Selector="^:fullscreen /template/ PathIcon#PART_FullScreenButtonIcon">
-            <Setter Property="Data" Value="{StaticResource WindowCollapseGlyph}" />
-        </Style>
-        <Style Selector="^:fullscreen /template/ Button#PART_RestoreButton">
-            <Setter Property="IsVisible" Value="False" />
-        </Style>
-        <Style Selector="^:fullscreen /template/ Button#PART_MinimizeButton">
-            <Setter Property="IsVisible" Value="False" />
-        </Style>
-    </ControlTheme>
-</ResourceDictionary>

src/Semi.Avalonia/Controls/TitleBar.axaml

@@ -1,53 +0,0 @@
-<ResourceDictionary
-    xmlns="https://github.com/avaloniaui"
-    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
-    <ControlTheme x:Key="{x:Type TitleBar}" TargetType="TitleBar">
-        <Setter Property="VerticalAlignment" Value="Top" />
-        <Setter Property="HorizontalAlignment" Value="Stretch" />
-        <Setter Property="Background" Value="Transparent" />
-        <Setter Property="Template">
-            <ControlTemplate>
-                <Panel HorizontalAlignment="{TemplateBinding HorizontalAlignment}" VerticalAlignment="Stretch">
-                    <Panel
-                        Name="PART_MouseTracker"
-                        Height="1"
-                        VerticalAlignment="Top" />
-                    <Panel Name="PART_Container">
-                        <Border
-                            Name="PART_Background"
-                            Background="{TemplateBinding Background}"
-                            IsHitTestVisible="False"
-                            Win32Properties.NonClientHitTestResult="Caption" />
-                        <CaptionButtons
-                            Name="PART_CaptionButtons"
-                            HorizontalAlignment="Right"
-                            VerticalAlignment="Top"
-                            Foreground="{TemplateBinding Foreground}"
-                            Win32Properties.NonClientHitTestResult="Client" />
-                    </Panel>
-                </Panel>
-            </ControlTemplate>
-        </Setter>
-
-        <Style Selector="^:fullscreen /template/ Border#PART_Background">
-            <Setter Property="IsHitTestVisible" Value="True" />
-        </Style>
-
-        <Style Selector="^:fullscreen /template/ Panel#PART_MouseTracker">
-            <Setter Property="Background" Value="Transparent" />
-        </Style>
-
-        <Style Selector="^:fullscreen /template/ Panel#PART_Container">
-            <Setter Property="RenderTransform" Value="translateY(-50px)" />
-            <Setter Property="Transitions">
-                <Transitions>
-                    <TransformOperationsTransition Property="RenderTransform" Duration="0:0:0.1" />
-                </Transitions>
-            </Setter>
-        </Style>
-
-        <Style Selector="^:fullscreen:pointerover /template/ Panel#PART_Container">
-            <Setter Property="RenderTransform" Value="none" />
-        </Style>
-    </ControlTheme>
-</ResourceDictionary>

src/Semi.Avalonia/Controls/Window.axaml

@@ -15,9 +15,6 @@
                     <Border Background="{TemplateBinding Background}" IsHitTestVisible="False" />
                     <Panel Margin="{TemplateBinding WindowDecorationMargin}" Background="Transparent" />
                     <VisualLayerManager>
-                        <VisualLayerManager.ChromeOverlayLayer>
-                            <TitleBar />
-                        </VisualLayerManager.ChromeOverlayLayer>
                         <ContentPresenter
                             Name="PART_ContentPresenter"
                             Margin="{TemplateBinding Padding}"

src/Semi.Avalonia/Controls/WindowDrawnDecorations.axaml

@@ -0,0 +1,206 @@
+<ResourceDictionary xmlns="https://github.com/avaloniaui" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
+
+    <ControlTheme x:Key="CaptionButton" TargetType="Button">
+        <Setter Property="Foreground" Value="{DynamicResource CaptionButtonForeground}" />
+        <Setter Property="Background" Value="Transparent" />
+        <Setter Property="CornerRadius" Value="{StaticResource CaptionButtonCornerRadius}" />
+        <Setter Property="Padding" Value="{StaticResource CaptionButtonPadding}" />
+        <Setter Property="Width" Value="{StaticResource CaptionButtonWidth}" />
+        <Setter Property="Height" Value="{StaticResource CaptionButtonHeight}" />
+        <Setter Property="Cursor" Value="Hand" />
+        <Setter Property="VerticalAlignment" Value="Stretch" />
+        <Setter Property="Template">
+            <ControlTemplate TargetType="Button">
+                <ContentPresenter
+                    Name="PART_ContentPresenter"
+                    Padding="{TemplateBinding Padding}"
+                    Background="{TemplateBinding Background}"
+                    BorderBrush="{TemplateBinding BorderBrush}"
+                    BorderThickness="{TemplateBinding BorderThickness}"
+                    Content="{TemplateBinding Content}"
+                    ContentTemplate="{TemplateBinding ContentTemplate}"
+                    CornerRadius="{TemplateBinding CornerRadius}"
+                    Foreground="{TemplateBinding Foreground}" />
+            </ControlTemplate>
+        </Setter>
+
+        <Style Selector="^:pointerover">
+            <Setter Property="Background" Value="{DynamicResource CaptionButtonPointeroverBackground}" />
+        </Style>
+
+        <Style Selector="^:pressed">
+            <Setter Property="Background" Value="{DynamicResource CaptionButtonPressedBackground}" />
+        </Style>
+    </ControlTheme>
+
+    <ControlTheme x:Key="{x:Type WindowDrawnDecorations}" TargetType="WindowDrawnDecorations">
+        <Setter Property="DefaultTitleBarHeight" Value="32" />
+        <Setter Property="DefaultFrameThickness" Value="1" />
+        <Setter Property="DefaultShadowThickness" Value="16" />
+        <Setter Property="Template">
+            <WindowDrawnDecorationsTemplate>
+                <WindowDrawnDecorationsContent>
+                    <WindowDrawnDecorationsContent.Underlay>
+                        <!--  Full-size: covers shadow area + frame + behind client area  -->
+                        <Panel>
+                            <Border
+                                x:Name="PART_WindowBorder"
+                                Margin="{TemplateBinding ShadowThickness}"
+                                Background="{DynamicResource WindowBackground}"
+                                BorderBrush="{DynamicResource WindowBorderBrush}"
+                                BorderThickness="1"
+                                BoxShadow="0 8 32 0 #40000000" />
+                            <!-- Titlebar: background, title text, and drag area live in underlay -->
+                            <Panel x:Name="PART_TitleBar" VerticalAlignment="Top"
+                                   Height="{TemplateBinding TitleBarHeight}"
+                                   Background="{DynamicResource SystemControlBackgroundAltHighBrush}"
+                                   IsVisible="{TemplateBinding HasTitleBar}"
+                                   WindowDecorationProperties.ElementRole="TitleBar" />
+                        </Panel>
+                    </WindowDrawnDecorationsContent.Underlay>
+
+                    <WindowDrawnDecorationsContent.Overlay>
+                        <!--  Positioned over the titlebar area  -->
+                        <Panel x:Name="PART_OverlayWrapper">
+                            <!--  Title text lives in overlay so it renders above client content  -->
+                            <Panel
+                                x:Name="PART_TitleTextPanel"
+                                Height="{TemplateBinding TitleBarHeight}"
+                                VerticalAlignment="Top"
+                                IsHitTestVisible="False"
+                                IsVisible="{TemplateBinding HasTitleBar}">
+                                <TextBlock
+                                    Margin="12,0,0,0"
+                                    VerticalAlignment="Center"
+                                    FontSize="12"
+                                    Text="{TemplateBinding Title}" />
+                            </Panel>
+                            <StackPanel
+                                x:Name="PART_OverlayPanel"
+                                Height="{TemplateBinding TitleBarHeight}"
+                                HorizontalAlignment="Right"
+                                VerticalAlignment="Top"
+                                IsVisible="{TemplateBinding HasTitleBar}"
+                                Orientation="Horizontal"
+                                Spacing="2"
+                                TextElement.FontSize="10">
+                                <Button
+                                    Name="PART_FullScreenButton"
+                                    Theme="{StaticResource CaptionButton}"
+                                    WindowDecorationProperties.ElementRole="FullScreenButton">
+                                    <PathIcon
+                                        Name="PART_FullScreenButtonIcon"
+                                        Data="{StaticResource WindowExpandGlyph}"
+                                        Foreground="{Binding $parent[Button].Foreground}"
+                                        Theme="{StaticResource InnerPathIcon}" />
+                                </Button>
+                                <Button
+                                    Name="PART_MinimizeButton"
+                                    AutomationProperties.Name="Minimize"
+                                    Theme="{StaticResource CaptionButton}"
+                                    WindowDecorationProperties.ElementRole="MinimizeButton">
+                                    <PathIcon
+                                        Name="PART_MinimizeButtonIcon"
+                                        Data="{StaticResource WindowMinimizeGlyph}"
+                                        Foreground="{Binding $parent[Button].Foreground}"
+                                        Theme="{StaticResource InnerPathIcon}" />
+                                </Button>
+                                <Button
+                                    Name="PART_MaximizeButton"
+                                    AutomationProperties.Name="Maximize"
+                                    Theme="{StaticResource CaptionButton}"
+                                    WindowDecorationProperties.ElementRole="MaximizeButton">
+                                    <PathIcon
+                                        Name="PART_MaximizeButtonIcon"
+                                        Data="{StaticResource WindowMaximizeGlyph}"
+                                        Foreground="{Binding $parent[Button].Foreground}"
+                                        Theme="{StaticResource InnerPathIcon}" />
+                                </Button>
+                                <Button
+                                    Name="PART_CloseButton"
+                                    AutomationProperties.Name="Close"
+                                    Theme="{StaticResource CaptionButton}"
+                                    WindowDecorationProperties.ElementRole="CloseButton">
+                                    <PathIcon
+                                        Name="PART_CloseButtonIcon"
+                                        Data="{StaticResource WindowCloseIconGlyph}"
+                                        Foreground="{Binding $parent[Button].Foreground}"
+                                        Theme="{StaticResource InnerPathIcon}" />
+                                </Button>
+                            </StackPanel>
+                        </Panel>
+                    </WindowDrawnDecorationsContent.Overlay>
+
+                    <WindowDrawnDecorationsContent.FullscreenPopover>
+                        <!--  Shown on hover at top edge in fullscreen  -->
+                        <DockPanel Height="{TemplateBinding TitleBarHeight}" Background="#E0000000">
+                            <StackPanel DockPanel.Dock="Right" Orientation="Horizontal">
+                                <Button
+                                    x:Name="PART_PopoverFullScreenButton"
+                                    Theme="{StaticResource CaptionButton}"
+                                    WindowDecorationProperties.ElementRole="FullScreenButton">
+                                    <PathIcon
+                                        Data="{StaticResource WindowCollapseGlyph}"
+                                        Foreground="{Binding $parent[Button].Foreground}"
+                                        Theme="{StaticResource InnerPathIcon}" />
+                                </Button>
+                            </StackPanel>
+                            <TextBlock
+                                Margin="12,0"
+                                VerticalAlignment="Center"
+                                Foreground="White"
+                                Text="{TemplateBinding Title}" />
+                        </DockPanel>
+                    </WindowDrawnDecorationsContent.FullscreenPopover>
+                </WindowDrawnDecorationsContent>
+            </WindowDrawnDecorationsTemplate>
+        </Setter>
+        
+        <Style Selector="^ /template/ Button#PART_CloseButton:pointerover">
+            <Setter Property="Foreground" Value="{DynamicResource CaptionButtonCloseForeground}" />
+            <Setter Property="Background" Value="{DynamicResource CaptionButtonClosePointeroverBackground}" />
+        </Style>
+        <Style Selector="^ /template/ Button#PART_CloseButton:pressed">
+            <Setter Property="Foreground" Value="{DynamicResource CaptionButtonCloseForeground}" />
+            <Setter Property="Background" Value="{DynamicResource CaptionButtonClosePressedBackground}" />
+        </Style>
+        
+        <!--  Shadow: inset border and add drop shadow  -->
+        <Style Selector="^:has-shadow /template/ Panel#PART_UnderlayWrapper">
+            <Setter Property="Margin" Value="{TemplateBinding ShadowThickness}" />
+        </Style>
+        <Style Selector="^:has-shadow /template/ Border#PART_WindowBorder">
+            <Setter Property="BoxShadow" Value="0 2 10 2 #80000000" />
+        </Style>
+        <Style Selector="^:has-shadow /template/ Panel#PART_OverlayWrapper">
+            <Setter Property="Margin" Value="{TemplateBinding ShadowThickness}" />
+        </Style>
+        
+        <!-- Maximized: restore button path changes -->
+        <Style Selector="^:maximized /template/ Path#PART_MaximizeButtonIcon">
+            <Setter Property="Data" Value="{StaticResource WindowRestoreGlyph}" />
+        </Style>
+
+        <!--  Border: inset titlebar and buttons inside frame  -->
+        <Style Selector="^:has-border /template/ Panel#PART_TitleTextPanel">
+            <Setter Property="Margin" Value="1,1,1,0" />
+        </Style>
+        <Style Selector="^:has-border /template/ Panel#PART_TitleBar">
+            <Setter Property="Margin" Value="1,1,1,0" />
+        </Style>
+        <Style Selector="^:has-border /template/ StackPanel#PART_OverlayPanel">
+            <Setter Property="Margin" Value="0,1,1,0" />
+        </Style>
+        
+        <!--  Fullscreen: hide overlay and titlebar (popover takes over)  -->
+        <Style Selector="^:fullscreen /template/ Panel#PART_TitleTextPanel">
+            <Setter Property="IsVisible" Value="False" />
+        </Style>
+        <Style Selector="^:fullscreen /template/ StackPanel#PART_OverlayPanel">
+            <Setter Property="IsVisible" Value="False" />
+        </Style>
+        <Style Selector="^:fullscreen /template/ Panel#PART_TitleBar">
+            <Setter Property="IsVisible" Value="False" />
+        </Style>
+    </ControlTheme>
+</ResourceDictionary>

src/Semi.Avalonia/Controls/_index.axaml

@@ -9,7 +9,6 @@
         <ResourceInclude Source="ButtonSpinner.axaml" />
         <ResourceInclude Source="Calendar.axaml" />
         <ResourceInclude Source="CalendarDatePicker.axaml" />
-        <ResourceInclude Source="CaptionButtons.axaml" />
         <ResourceInclude Source="Carousel.axaml" />
         <ResourceInclude Source="CheckBox.axaml" />
         <ResourceInclude Source="ComboBox.axaml" />
@@ -51,13 +50,13 @@
         <ResourceInclude Source="TextBox.axaml" />
         <ResourceInclude Source="ThemeVariantScope.axaml" />
         <ResourceInclude Source="TimePicker.axaml" />
-        <ResourceInclude Source="TitleBar.axaml" />
         <ResourceInclude Source="ToggleButton.axaml" />
         <ResourceInclude Source="ToggleSwitch.axaml" />
         <ResourceInclude Source="Tooltip.axaml" />
         <ResourceInclude Source="TransitioningContentControl.axaml" />
         <ResourceInclude Source="TreeView.axaml" />
         <ResourceInclude Source="Window.axaml" />
+        <ResourceInclude Source="WindowDrawnDecorations.axaml" />
         <ResourceInclude Source="WindowNotificationManager.axaml" />
     </ResourceDictionary.MergedDictionaries>
 </ResourceDictionary>