希望在MiTabItem左侧添加图标，替换原来得圆圈+汉字的方式。

我在TextBlock下面添加了Border，发现不行，，

```

<Setter Property="Template">

<Setter.Value>

<ControlTemplate TargetType="{x:Type Mi:MiTabItem}">

<Grid Background="#00000000">

<Grid.ColumnDefinitions>

<ColumnDefinition x:Name="headerWidth" Width="46"/>

<ColumnDefinition x:Name="contentWidth" Width="*"/>

</Grid.ColumnDefinitions>

<VisualStateManager.VisualStateGroups>

<VisualStateGroup x:Name="CommonStates">

<VisualState x:Name="Normal"/>

<VisualState x:Name="MouseOver">

<Storyboard>

<DoubleAnimation Storyboard.TargetName="back" Storyboard.TargetProperty="(UIElement.Opacity)" To="0.2" Duration="0:0:0.2"/>

<ColorAnimation Storyboard.TargetName="title" Storyboard.TargetProperty="(TextBlock.Foreground).(SolidColorBrush.Color)" To="#A5000000" Duration="0:0:0.2"/>

<ColorAnimation Storyboard.TargetName="idxHeader" Storyboard.TargetProperty="(TextBlock.Foreground).(SolidColorBrush.Color)" To="#A5000000" Duration="0:0:0.2"/>

</Storyboard>

</VisualState>

<VisualState x:Name="Pressed">

</VisualState>

<VisualState x:Name="Disabled"/>

</VisualStateGroup>

</VisualStateManager.VisualStateGroups>

<Rectangle x:Name="back" Grid.ColumnSpan="2" Fill="#f3f3f3" Opacity="0"/>

<Canvas Margin="10.01">

<!--加小数是因为125%显示时轻微错位-->

<Ellipse x:Name="iconHeader" Height="26" Width="26" Stroke="#E5FFFFFF" Fill="{TemplateBinding BorderBrush}"/>

</Canvas>

<TextBlock x:Name="idxHeader" Foreground="#E5FFFFFF" Text="{TemplateBinding IdxHeader}" FontSize="10" Margin="10" HorizontalAlignment="Center" VerticalAlignment="Center" TextAlignment="Center"/>

<Border BorderBrush="WhiteSmoke" BorderThickness="0" Grid.Column="0" Margin="5">

<StackPanel Name="aPanel" Width="40" Height="40" Orientation="Horizontal">

<!--<TextBlock Name="aBlock" VerticalAlignment="Center" Text="A"/>-->

<Image Name="aImage" Width="32" Height="32" Source="{TemplateBinding Image}"/>

</StackPanel>

</Border>

<TextBlock x:Name="title" Grid.Column="2" Foreground="#E5FFFFFF" Text="{TemplateBinding Header}" FontSize="{TemplateBinding FontSize}" Margin="0,0,12,0" VerticalAlignment="Center" HorizontalAlignment="{TemplateBinding TextHorizontalAlignment}"/>

</Grid>

<ControlTemplate.Triggers>

<Trigger Property="Selector.IsSelected" Value="True">

<Setter TargetName="back" Property="Opacity" Value="0.2"/>

<Setter TargetName="title" Property="Foreground" Value="#A5000000"/>

<Setter TargetName="idxHeader" Property="Foreground" Value="#A5000000"/>

<Setter TargetName="iconHeader" Property="Stroke" Value="#A5000000"/>

</Trigger>

<Trigger Property="IdxHeader" Value="{x:Null}">

<Setter TargetName="headerWidth" Property="Width" Value="0"/>

<Setter TargetName="title" Property="Margin" Value="16,0"/>

</Trigger>

<Trigger Property="IsMouseOver" Value="True">

<Setter TargetName="iconHeader" Property="Stroke" Value="#A5000000"/>

</Trigger>

</ControlTemplate.Triggers>

</ControlTemplate>

</Setter.Value>

</Setter>

```