feat: introduce Small class and IsReadOnly property.

demo/Ursa.Demo/Pages/BreadcrumbDemo.axaml

@@ -23,6 +23,18 @@
             <TextBlock Text="Avalonia" />
             <TextBlock Text="Ursa" />
         </u:Breadcrumb>
+        <u:Breadcrumb Classes="Small">
+            <TextBlock Text="Hello" />
+            <u:BreadcrumbItem Icon="?" Separator="♥" />
+            <TextBlock Text="Avalonia" />
+            <TextBlock Text="Ursa" />
+        </u:Breadcrumb>
+        <u:Breadcrumb IsReadOnly="True">
+            <TextBlock Text="Hello" />
+            <u:BreadcrumbItem Icon="?" Separator="♥" />
+            <TextBlock Text="Avalonia" />
+            <TextBlock Text="Ursa" />
+        </u:Breadcrumb>
         <u:Breadcrumb
             DisplayMemberBinding="{Binding Section}"
             IconBinding="{Binding Icon}"

src/Ursa.Themes.Semi/Controls/Breadcrumb.axaml

@@ -19,17 +19,20 @@
                 <ItemsPresenter ItemsPanel="{TemplateBinding ItemsPanel}" />
             </ControlTemplate>
         </Setter>
+        <Style Selector="^[IsReadOnly=True]">
+            <Setter Property="ItemContainerTheme" Value="{DynamicResource ReadOnlyBreadcrumbItem}"></Setter>
+        </Style>
     </ControlTheme>
 
     <ControlTheme x:Key="{x:Type u:BreadcrumbItem}" TargetType="u:BreadcrumbItem">
-        <Setter Property="Cursor" Value="Hand"></Setter>
+        <Setter Property="Cursor" Value="Hand" />
         <Setter Property="Template">
             <ControlTemplate TargetType="u:BreadcrumbItem">
                 <Border Background="Transparent">
                     <StackPanel Orientation="Horizontal">
                         <ContentPresenter
                             Name="PART_IconPresenter"
-                            Margin="0 0 4 0"
+                            Margin="0,0,4,0"
                             VerticalAlignment="Center"
                             Content="{TemplateBinding Icon}"
                             ContentTemplate="{TemplateBinding IconTemplate}"
@@ -39,14 +42,19 @@
                         <ContentPresenter
                             Name="PART_ContentPresenter"
                             VerticalAlignment="Center"
-                            IsVisible="{TemplateBinding Content,
-                                        Converter={x:Static ObjectConverters.IsNotNull}}"
-                            Foreground="{DynamicResource SemiColorText2}"
                             Content="{TemplateBinding Content}"
-                            ContentTemplate="{TemplateBinding ContentTemplate}" />
+                            ContentTemplate="{TemplateBinding ContentTemplate}"
-                        <ContentPresenter Name="Separator" VerticalAlignment="Center" Content="{TemplateBinding Separator}" Foreground="{DynamicResource SemiColorText3}" Margin="4 0">
+                            Foreground="{DynamicResource SemiColorText2}"
+                            IsVisible="{TemplateBinding Content,
+                                                        Converter={x:Static ObjectConverters.IsNotNull}}" />
+                        <ContentPresenter
+                            Name="Separator"
+                            Margin="4,0 0 0"
+                            VerticalAlignment="Center"
+                            Content="{TemplateBinding Separator}"
+                            Foreground="{DynamicResource SemiColorText3}">
                             <ContentPresenter.IsVisible>
-                                <TemplateBinding Property="Separator" Converter="{x:Static ObjectConverters.IsNotNull}" />
+                                <TemplateBinding Converter="{x:Static ObjectConverters.IsNotNull}" Property="Separator" />
                             </ContentPresenter.IsVisible>
                         </ContentPresenter>
                     </StackPanel>
@@ -82,4 +90,55 @@
             </Style>
         </Style>
     </ControlTheme>
+    
+    <ControlTheme x:Key="ReadOnlyBreadcrumbItem" TargetType="u:BreadcrumbItem">
+        <Setter Property="Cursor" Value="Hand" />
+        <Setter Property="Template">
+            <ControlTemplate TargetType="u:BreadcrumbItem">
+                <Border Background="Transparent">
+                    <StackPanel Orientation="Horizontal">
+                        <ContentPresenter
+                            Name="PART_IconPresenter"
+                            Margin="0,0,4,0"
+                            VerticalAlignment="Center"
+                            Content="{TemplateBinding Icon}"
+                            ContentTemplate="{TemplateBinding IconTemplate}"
+                            Foreground="{DynamicResource SemiColorText2}"
+                            IsVisible="{TemplateBinding Icon,
+                                                        Converter={x:Static ObjectConverters.IsNotNull}}" />
+                        <ContentPresenter
+                            Name="PART_ContentPresenter"
+                            VerticalAlignment="Center"
+                            Content="{TemplateBinding Content}"
+                            ContentTemplate="{TemplateBinding ContentTemplate}"
+                            Foreground="{DynamicResource SemiColorText2}"
+                            IsVisible="{TemplateBinding Content,
+                                                        Converter={x:Static ObjectConverters.IsNotNull}}" />
+                        <ContentPresenter
+                            Name="Separator"
+                            Margin="4,0 0 0"
+                            VerticalAlignment="Center"
+                            Content="{TemplateBinding Separator}"
+                            Foreground="{DynamicResource SemiColorText3}">
+                            <ContentPresenter.IsVisible>
+                                <TemplateBinding Converter="{x:Static ObjectConverters.IsNotNull}" Property="Separator" />
+                            </ContentPresenter.IsVisible>
+                        </ContentPresenter>
+                    </StackPanel>
+                </Border>
+            </ControlTemplate>
+        </Setter>
+        <Style Selector="^:last">
+            <Style Selector="^ /template/ ContentPresenter#PART_IconPresenter">
+                <Setter Property="Foreground" Value="{DynamicResource SemiColorText0}" />
+            </Style>
+            <Style Selector="^ /template/ ContentPresenter#PART_ContentPresenter">
+                <Setter Property="Foreground" Value="{DynamicResource SemiColorText0}" />
+                <Setter Property="FontWeight" Value="Bold" />
+            </Style>
+            <Style Selector="^ /template/ ContentPresenter#Separator">
+                <Setter Property="IsVisible" Value="False" />
+            </Style>
+        </Style>
+    </ControlTheme>
 </ResourceDictionary>

src/Ursa.Themes.Semi/Styles/Breadcrumb.axaml

@@ -0,0 +1,20 @@
+<Styles xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:u="https://irihi.tech/ursa">
+    <Design.PreviewWith>
+        <Border Padding="20">
+            <!-- Add Controls for Previewer Here -->
+        </Border>
+    </Design.PreviewWith>
+
+    <!-- Add Styles Here -->
+    <Style Selector="u|Breadcrumb.Small u|BreadcrumbItem /template/ ContentPresenter">
+        <Setter Property="FontSize" Value="12"></Setter>
+    </Style>
+    <Style Selector="u|Breadcrumb.Small u|BreadcrumbItem /template/ ContentPresenter#PART_IconPresenter">
+        <Setter Property="Margin" Value="0 0 2 0"></Setter>
+    </Style>
+    <Style Selector="u|Breadcrumb.Small u|BreadcrumbItem /template/ ContentPresenter#Separator">
+        <Setter Property="Margin" Value="2 0 0 0"></Setter>
+    </Style>
+</Styles>

src/Ursa.Themes.Semi/Styles/_index.axaml

@@ -4,6 +4,7 @@
             <!--  Add Controls for Previewer Here  -->
         </Border>
     </Design.PreviewWith>
+    <StyleInclude Source="Breadcrumb.axaml" />
     <StyleInclude Source="ButtonGroup.axaml" />
     <StyleInclude Source="Skeleton.axaml" />
     <StyleInclude Source="ToolBar.axaml"/>

src/Ursa/Controls/BackTop/BackTop.cs

@@ -0,0 +1,15 @@
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Controls.Primitives;
+using Avalonia.Media;
+
+namespace Ursa.Controls.BackTop;
+
+public class BackTop: Control
+{
+    public static readonly AttachedProperty<bool> AttachProperty =
+        AvaloniaProperty.RegisterAttached<BackTop, Control, bool>("Attach");
+
+    public static void SetAttach(Control obj, bool value) => obj.SetValue(AttachProperty, value);
+    public static bool GetAttach(Control obj) => obj.GetValue(AttachProperty);
+}

src/Ursa/Controls/Breadcrumb/Breadcrumb.cs

@@ -57,6 +57,15 @@ public class Breadcrumb: ItemsControl
         set => SetValue(IconTemplateProperty, value);
     }
 
+    public static readonly StyledProperty<bool> IsReadOnlyProperty = AvaloniaProperty.Register<Breadcrumb, bool>(
+        nameof(IsReadOnly));
+
+    public bool IsReadOnly
+    {
+        get => GetValue(IsReadOnlyProperty);
+        set => SetValue(IsReadOnlyProperty, value);
+    }
+    
     static Breadcrumb()
     {
         ItemsPanelProperty.OverrideDefaultValue<Breadcrumb>(_defaultPanel);

src/Ursa/Controls/Breadcrumb/BreadcrumbItem.cs

@@ -4,6 +4,7 @@ using Avalonia.Controls;
 using Avalonia.Controls.Metadata;
 using Avalonia.Controls.Templates;
 using Avalonia.Input;
+using Avalonia.LogicalTree;
 
 namespace Ursa.Controls;
 
@@ -51,6 +52,10 @@ public class BreadcrumbItem: ContentControl
     protected override void OnPointerPressed(PointerPressedEventArgs e)
     {
         base.OnPointerPressed(e);
+        var parent = this.FindLogicalAncestorOfType<Breadcrumb>();
+        if (parent?.IsReadOnly != true)
+        {
             Command?.Execute(null);
         }
     }
+}