fix: fix issues in TabControl.

src/Semi.Avalonia/Controls/TabControl.axaml

@@ -3,9 +3,6 @@
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     x:CompileBindings="True">
     <ControlTheme x:Key="{x:Type TabControl}" TargetType="TabControl">
-        <Setter Property="Margin" Value="0" />
-        <Setter Property="Padding" Value="0" />
-        <Setter Property="Background" Value="{DynamicResource TabControlBackground}" />
         <Setter Property="Template">
             <ControlTemplate TargetType="TabControl">
                 <Border
@@ -17,8 +14,12 @@
                     CornerRadius="{TemplateBinding CornerRadius}">
                     <DockPanel>
                         <Panel DockPanel.Dock="{TemplateBinding TabStripPlacement}">
-                            <ItemsPresenter Name="PART_ItemsPresenter" ItemsPanel="{TemplateBinding ItemsPanel}" />
-                            <Border Name="PART_BorderSeparator" Background="{DynamicResource TabItemLinePipePressedBorderBrush}" />
+                            <ItemsPresenter
+                                Name="PART_ItemsPresenter"
+                                ItemsPanel="{TemplateBinding ItemsPanel}" />
+                            <Border
+                                Name="PART_BorderSeparator"
+                                Background="{DynamicResource TabItemLinePipePressedBorderBrush}" />
                         </Panel>
                         <ContentPresenter
                             Name="PART_SelectedContentHost"
@@ -32,11 +33,12 @@
             </ControlTemplate>
         </Setter>
 
-        <Style Selector="^[TabStripPlacement=Left] /template/ ItemsPresenter#PART_ItemsPresenter > WrapPanel">
-            <Setter Property="Orientation" Value="Vertical" />
-        </Style>
-        <Style Selector="^[TabStripPlacement=Right] /template/ ItemsPresenter#PART_ItemsPresenter > WrapPanel">
-            <Setter Property="Orientation" Value="Vertical" />
+        <Style Selector="^[TabStripPlacement=Left], ^[TabStripPlacement=Right]">
+            <Setter Property="TabControl.ItemsPanel">
+                <ItemsPanelTemplate>
+                    <WrapPanel Orientation="Vertical" />
+                </ItemsPanelTemplate>
+            </Setter>
         </Style>
         <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
             <Setter Property="Width" Value="1" />
@@ -58,17 +60,9 @@
             <Setter Property="HorizontalAlignment" Value="Stretch" />
             <Setter Property="VerticalAlignment" Value="Top" />
         </Style>
-        <!--
-        <Style Selector="^[TabStripPlacement=Top] /template/ ItemsPresenter#PART_ItemsPresenter">
-            <Setter Property="Margin" Value="8" />
-        </Style>
-        -->
     </ControlTheme>
 
     <ControlTheme x:Key="ScrollTabControl" TargetType="TabControl">
-        <Setter Property="Margin" Value="0" />
-        <Setter Property="Padding" Value="0" />
-        <Setter Property="Background" Value="{DynamicResource TabControlBackground}" />
         <Setter Property="ItemsPanel">
             <ItemsPanelTemplate>
                 <VirtualizingStackPanel Orientation="Horizontal" />
@@ -85,10 +79,18 @@
                     CornerRadius="{TemplateBinding CornerRadius}">
                     <DockPanel>
                         <Panel DockPanel.Dock="{TemplateBinding TabStripPlacement}">
-                            <ScrollViewer Name="PART_ScrollViewer">
-                                <ItemsPresenter Name="PART_ItemsPresenter" ItemsPanel="{TemplateBinding ItemsPanel}" Margin="0 0 12 12" />
+                            <ScrollViewer
+                                Name="PART_ScrollViewer"
+                                HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}"
+                                VerticalScrollBarVisibility="{TemplateBinding ScrollViewer.VerticalScrollBarVisibility}">
+                                <ItemsPresenter
+                                    Name="PART_ItemsPresenter"
+                                    ItemsPanel="{TemplateBinding ItemsPanel}"
+                                    Margin="0 0 12 12" />
                             </ScrollViewer>
-                            <Border Name="PART_BorderSeparator" Background="{DynamicResource TabItemLinePipePressedBorderBrush}" />
+                            <Border
+                                Name="PART_BorderSeparator"
+                                Background="{DynamicResource TabItemLinePipePressedBorderBrush}" />
                         </Panel>
                         <ContentPresenter
                             Name="PART_SelectedContentHost"
@@ -103,32 +105,11 @@
         </Setter>
 
         <Style Selector="^[TabStripPlacement=Left], ^[TabStripPlacement=Right]">
-            <Style Selector="^ /template/ ItemsPresenter">
-                <Setter Property="ItemsPanel">
-                    <ItemsPanelTemplate>
-                        <VirtualizingStackPanel Orientation="Vertical" />
-                    </ItemsPanelTemplate>
-                </Setter>
-            </Style>
-        </Style>
-        <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
-            <Setter Property="Width" Value="1" />
-            <Setter Property="VerticalAlignment" Value="Stretch" />
-            <Setter Property="HorizontalAlignment" Value="Left" />
-        </Style>
-        <Style Selector="^[TabStripPlacement=Left] /template/ ScrollViewer#PART_ScrollViewer">
-            <Setter Property="HorizontalScrollBarVisibility" Value="Disabled" />
-            <Setter Property="VerticalScrollBarVisibility" Value="Auto" />
-        </Style>
-        <Style Selector="^[TabStripPlacement=Right] /template/ Border#PART_BorderSeparator">
-            <Setter Property="Width" Value="1" />
-            <Setter Property="VerticalAlignment" Value="Stretch" />
-            <Setter Property="HorizontalAlignment" Value="Right" />
-            <Setter Property="Margin" Value="0 0 12 0" />
-        </Style>
-        <Style Selector="^[TabStripPlacement=Right] /template/ ScrollViewer#PART_ScrollViewer">
-            <Setter Property="HorizontalScrollBarVisibility" Value="Disabled" />
-            <Setter Property="VerticalScrollBarVisibility" Value="Auto" />
+            <Setter Property="TabControl.ItemsPanel">
+                <ItemsPanelTemplate>
+                    <VirtualizingStackPanel />
+                </ItemsPanelTemplate>
+            </Setter>
         </Style>
         <Style Selector="^[TabStripPlacement=Top] /template/ Border#PART_BorderSeparator">
             <Setter Property="Height" Value="1" />
@@ -136,18 +117,37 @@
             <Setter Property="VerticalAlignment" Value="Bottom" />
             <Setter Property="Margin" Value="0 0 0 12" />
         </Style>
-        <Style Selector="^[TabStripPlacement=Top] /template/ ScrollViewer#PART_ScrollViewer">
-            <Setter Property="HorizontalScrollBarVisibility" Value="Auto" />
-            <Setter Property="VerticalScrollBarVisibility" Value="Disabled" />
-        </Style>
         <Style Selector="^[TabStripPlacement=Bottom] /template/ Border#PART_BorderSeparator">
             <Setter Property="Height" Value="1" />
             <Setter Property="HorizontalAlignment" Value="Stretch" />
             <Setter Property="VerticalAlignment" Value="Top" />
         </Style>
-        <Style Selector="^[TabStripPlacement=Bottom] /template/ ScrollViewer#PART_ScrollViewer">
-            <Setter Property="HorizontalScrollBarVisibility" Value="Auto" />
-            <Setter Property="VerticalScrollBarVisibility" Value="Disabled" />
+        <Style Selector="^[TabStripPlacement=Left] /template/ Border#PART_BorderSeparator">
+            <Setter Property="Width" Value="1" />
+            <Setter Property="VerticalAlignment" Value="Stretch" />
+            <Setter Property="HorizontalAlignment" Value="Left" />
+        </Style>
+        <Style Selector="^[TabStripPlacement=Right] /template/ Border#PART_BorderSeparator">
+            <Setter Property="Width" Value="1" />
+            <Setter Property="VerticalAlignment" Value="Stretch" />
+            <Setter Property="HorizontalAlignment" Value="Right" />
+            <Setter Property="Margin" Value="0 0 12 0" />
+        </Style>
+        <Style Selector="^[TabStripPlacement=Top]">
+            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto" />
+            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Disabled" />
+        </Style>
+        <Style Selector="^[TabStripPlacement=Bottom]">
+            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto" />
+            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Disabled" />
+        </Style>
+        <Style Selector="^[TabStripPlacement=Left]">
+            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled" />
+            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto" />
+        </Style>
+        <Style Selector="^[TabStripPlacement=Right]">
+            <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Disabled" />
+            <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto" />
         </Style>
     </ControlTheme>
 </ResourceDictionary>

src/Semi.Avalonia/Controls/TabItem.axaml

@@ -14,7 +14,6 @@
     <ControlTheme x:Key="{x:Type TabItem}" TargetType="TabItem">
         <Setter Property="Background" Value="{DynamicResource TabItemLinePipeBackground}" />
         <Setter Property="Foreground" Value="{DynamicResource TabItemLineHeaderForeground}" />
-        <Setter Property="Margin" Value="0" />
         <Setter Property="Padding" Value="8 4" />
         <Setter Property="MinHeight" Value="5" />
         <Setter Property="VerticalContentAlignment" Value="Center" />
@@ -70,12 +69,6 @@
             <Setter Property="Background" Value="{DynamicResource TabItemLinePipeSelectedBackground}" />
         </Style>
 
-        <!--  Selected Pressed state  -->
-        <Style Selector="^:selected:pressed /template/ Border#PART_LayoutRoot">
-            <Setter Property="Background" Value="{DynamicResource TabItemHeaderBackgroundSelectedPressed}" />
-            <Setter Property="TextElement.Foreground" Value="{DynamicResource TabItemHeaderForegroundSelectedPressed}" />
-        </Style>
-
         <!--  Disabled state  -->
         <Style Selector="^:disabled /template/ Border#PART_LayoutRoot">
             <Setter Property="Background" Value="{DynamicResource TabItemHeaderBackgroundDisabled}" />
@@ -84,7 +77,7 @@
 
         <!--  TabStripPlacement States Group  -->
         <Style Selector="^[TabStripPlacement=Top]">
-            <Style Selector="^ /template/Border#PART_SelectedPipe">
+            <Style Selector="^ /template/ Border#PART_SelectedPipe">
                 <Setter Property="Height" Value="2" />
                 <Setter Property="Margin" Value="0" />
                 <Setter Property="HorizontalAlignment" Value="Stretch" />
@@ -95,7 +88,7 @@
             </Style>
         </Style>
         <Style Selector="^[TabStripPlacement=Bottom]">
-            <Style Selector="^ /template/Border#PART_SelectedPipe">
+            <Style Selector="^ /template/ Border#PART_SelectedPipe">
                 <Setter Property="Height" Value="2" />
                 <Setter Property="Margin" Value="0" />
                 <Setter Property="HorizontalAlignment" Value="Stretch" />
@@ -112,7 +105,7 @@
                 <Setter Property="HorizontalAlignment" Value="Left" />
                 <Setter Property="VerticalAlignment" Value="Stretch" />
             </Style>
-            <Style Selector="^ /template/ Label#PART_ContentPresenter">
+            <Style Selector="^ /template/ ContentPresenter#PART_ContentPresenter">
                 <Setter Property="Margin" Value="8,0,0,0" />
             </Style>
         </Style>
@@ -129,5 +122,4 @@
             </Style>
         </Style>
     </ControlTheme>
-
 </ResourceDictionary>