feat: implement inner content interface.

demo/Ursa.Demo/Pages/MultiAutoCompleteBoxDemo.axaml

@@ -7,9 +7,11 @@
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
              x:DataType="vm:MultiAutoCompleteBoxDemoViewModel"
              x:Class="Ursa.Demo.Pages.MultiAutoCompleteBoxDemo">
-    <StackPanel Spacing="20">
+    <StackPanel Spacing="20" HorizontalAlignment="Left">
         <TextBlock Text="Multi-AutoCompleteBox"/>
         <u:MultiAutoCompleteBox ItemsSource="{Binding Items}" 
+                                MaxWidth="400"
+                                InnerLeftContent="Controls"
                                 SelectedItems="{Binding SelectedItems}"
                                 ItemFilter="{Binding FilterPredicate }"
                                 FilterMode="Custom">

demo/Ursa.Demo/ViewModels/MultiAutoCompleteBoxDemoViewModel.cs

@@ -1,4 +1,5 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using Avalonia.Controls;
 using CommunityToolkit.Mvvm.ComponentModel;
@@ -82,12 +83,13 @@ public class MultiAutoCompleteBoxDemoViewModel: ObservableObject
     {
         if (text is null) return true;
         if (data is not ControlData control) return false;
-        return control.MenuHeader.Contains(text )|| control.Chinese.Contains(text);
+        return control.MenuHeader.Contains(text, StringComparison.InvariantCultureIgnoreCase) ||
+               control.Chinese.Contains(text, StringComparison.InvariantCultureIgnoreCase);
     }
 }
 
 public class ControlData
 {
-    public string MenuHeader { get; set; }
+    public required string MenuHeader { get; init; }
-    public string Chinese { get; set; }
+    public required string Chinese { get; init; }
 }

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

@@ -12,12 +12,22 @@
                     <Border
                         Name="PART_RootBorder"
                         MinHeight="30"
-                        Padding="{DynamicResource TextBoxContentPadding}"
                         VerticalAlignment="Stretch"
                         CornerRadius="{TemplateBinding CornerRadius}"
                         Background="{DynamicResource TextBoxDefaultBackground}"
                         BorderBrush="{DynamicResource TextBoxDefaultBorderBrush}">
+                        <Grid ColumnDefinitions="Auto, *, Auto">
+                            <ContentPresenter
+                                Grid.Column="0"
+                                Margin="8,0"
+                                IsHitTestVisible="False"
+                                VerticalAlignment="Center"
+                                Content="{TemplateBinding InnerLeftContent}"
+                                Foreground="{DynamicResource TextBoxInnerForeground}"
+                                IsVisible="{TemplateBinding InnerLeftContent,
+                                                                Converter={x:Static ObjectConverters.IsNotNull}}" />
                             <u:MultiComboBoxSelectedItemList
+                                Grid.Column="1"
                                 Name="{x:Static u:MultiAutoCompleteBox.PART_SelectedItemsControl}"
                                 VerticalAlignment="Center"
                                 RemoveCommand="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=Remove}"
@@ -33,6 +43,16 @@
                                     </ItemsPanelTemplate>
                                 </u:MultiComboBoxSelectedItemList.ItemsPanel>
                             </u:MultiComboBoxSelectedItemList>
+                            <ContentPresenter
+                                Grid.Column="2"
+                                Margin="8,0"
+                                VerticalAlignment="Center"
+                                IsHitTestVisible="False"
+                                Content="{TemplateBinding InnerRightContent}"
+                                Foreground="{DynamicResource TextBoxInnerForeground}"
+                                IsVisible="{TemplateBinding InnerRightContent,
+                                                                Converter={x:Static ObjectConverters.IsNotNull}}" />
+                        </Grid>
                     </Border>
                     <Popup
                         Name="PART_Popup"
@@ -49,12 +69,16 @@
                             BorderThickness="{DynamicResource AutoCompleteBoxPopupBorderThickness}"
                             BoxShadow="{DynamicResource AutoCompleteBoxPopupBoxShadow}"
                             CornerRadius="{DynamicResource AutoCompleteBoxPopupCornerRadius}">
+                            <DockPanel LastChildFill="True">
+                                <ContentPresenter Content="{TemplateBinding PopupInnerTopContent}" DockPanel.Dock="Top" />
+                                <ContentPresenter Content="{TemplateBinding PopupInnerBottomContent}" DockPanel.Dock="Bottom" />
                                 <ListBox
                                     Name="PART_SelectingItemsControl"
                                     Foreground="{TemplateBinding Foreground}"
                                     ItemTemplate="{TemplateBinding ItemTemplate}"
                                     ScrollViewer.HorizontalScrollBarVisibility="Auto"
                                     ScrollViewer.VerticalScrollBarVisibility="Auto" />
+                            </DockPanel>
                         </Border>
                     </Popup>
                 </Panel>

src/Ursa/Controls/AutoCompleteBox/MultiAutoCompleteBox.Properties.cs

@@ -512,4 +512,22 @@ public partial class MultiAutoCompleteBox
             get => GetValue(InnerRightContentProperty);
             set => SetValue(InnerRightContentProperty, value);
         }
+        
+        public static readonly StyledProperty<object?> PopupInnerTopContentProperty = AvaloniaProperty.Register<MultiAutoCompleteBox, object?>(
+            nameof(PopupInnerTopContent));
+
+        public object? PopupInnerTopContent
+        {
+            get => GetValue(PopupInnerTopContentProperty);
+            set => SetValue(PopupInnerTopContentProperty, value);
+        }
+
+        public static readonly StyledProperty<object?> PopupInnerBottomContentProperty = AvaloniaProperty.Register<MultiAutoCompleteBox, object?>(
+            nameof(PopupInnerBottomContent));
+
+        public object? PopupInnerBottomContent
+        {
+            get => GetValue(PopupInnerBottomContentProperty);
+            set => SetValue(PopupInnerBottomContentProperty, value);
+        }
     }

src/Ursa/Controls/AutoCompleteBox/MultiAutoCompleteBox.cs

@@ -30,7 +30,7 @@ namespace Ursa.Controls;
 [TemplatePart(ElementSelectionAdapter, typeof(ISelectionAdapter))]
 [TemplatePart(ElementTextBox, typeof(TextBox))]
 [PseudoClasses(":dropdownopen")]
-public partial class MultiAutoCompleteBox : TemplatedControl, IInnerContentControl
+public partial class MultiAutoCompleteBox : TemplatedControl, IInnerContentControl, IPopupInnerContent
 {
     /// <summary>
     ///     Specifies the name of the selection adapter TemplatePart.