wpf - 将图标放在 WPF 扩展器控件的右端

Question

嗨，我试图在设置复选框时在 WPF Expander 控件的右端放置一个绿色刻度图标。我目前的代码是:

<Expander x:Name="ImageExpander">
    <Expander.Header>
        <Grid Width="450">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="*" />
                <ColumnDefinition Width="Auto" />
            </Grid.ColumnDefinitions>
            <Label Padding="0">My Header Text</Label>
            <Image Grid.Column="1" Margin="0"
                   Source="C:\...\GreenTick.png" Width="18" />
        </Grid>
    </Expander.Header>
</Expander>

我使用网格将图标放在扩展器的右上角。这会将标题文本放在旋转扩展器旁边的常用位置，以扩展扩展器。它还在扩展器的右端附近放置了一个 450 像素的图标。

我希望它不会被硬编码，这样无论扩展器增长多宽，图标都会保持在右上角。任何人都可以建议如何做到这一点？

我尝试将 expander.header 的宽度绑定(bind)到扩展器的宽度，但没有成功。

感谢您的任何建议!

Answer 1

这是因为扩展器的默认模板 (ToggleButton ContentPresenter)。
这是修改后的模板，看看这是您需要的结果

<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
x:Class="WpfApplication19.MainWindow"
x:Name="Window"
Title="MainWindow"
Width="640" Height="480">
<Window.Resources>
    <Style x:Key="ExpanderRightHeaderStyle" TargetType="{x:Type ToggleButton}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ToggleButton}">
                    <Border Padding="{TemplateBinding Padding}">
                        <Grid SnapsToDevicePixels="False" Background="Transparent">
                            <Grid.RowDefinitions>
                                <RowDefinition Height="19"/>
                                <RowDefinition Height="*"/>
                            </Grid.RowDefinitions>
                            <Grid>
                                <Grid.LayoutTransform>
                                    <TransformGroup>
                                        <TransformGroup.Children>
                                            <TransformCollection>
                                                <RotateTransform Angle="-90"/>
                                            </TransformCollection>
                                        </TransformGroup.Children>
                                    </TransformGroup>
                                </Grid.LayoutTransform>
                                <Ellipse x:Name="circle" Stroke="DarkGray" HorizontalAlignment="Center" VerticalAlignment="Center" Width="19" Height="19"/>
                                <Path x:Name="arrow" Stroke="#666" StrokeThickness="2" HorizontalAlignment="Center" VerticalAlignment="Center" SnapsToDevicePixels="false" Data="M 1,1.5 L 4.5,5 L 8,1.5"/>
                            </Grid>
                            <ContentPresenter HorizontalAlignment="Center" Margin="0,4,0,0" VerticalAlignment="Top" SnapsToDevicePixels="True" Grid.Row="1" RecognizesAccessKey="True"/>
                        </Grid>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsChecked" Value="true">
                            <Setter Property="Data" TargetName="arrow" Value="M 1,4.5  L 4.5,1  L 8,4.5"/>
                        </Trigger>
                        <Trigger Property="IsMouseOver" Value="true">
                            <Setter Property="Stroke" TargetName="circle" Value="#FF3C7FB1"/>
                            <Setter Property="Stroke" TargetName="arrow" Value="#222"/>
                        </Trigger>
                        <Trigger Property="IsPressed" Value="true">
                            <Setter Property="Stroke" TargetName="circle" Value="#FF526C7B"/>
                            <Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
                            <Setter Property="Stroke" TargetName="arrow" Value="#FF003366"/>
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <Style x:Key="ExpanderUpHeaderStyle" TargetType="{x:Type ToggleButton}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ToggleButton}">
                    <Border Padding="{TemplateBinding Padding}">
                        <Grid SnapsToDevicePixels="False" Background="Transparent">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="19"/>
                                <ColumnDefinition Width="*"/>
                            </Grid.ColumnDefinitions>
                            <Grid>
                                <Grid.LayoutTransform>
                                    <TransformGroup>
                                        <TransformGroup.Children>
                                            <TransformCollection>
                                                <RotateTransform Angle="180"/>
                                            </TransformCollection>
                                        </TransformGroup.Children>
                                    </TransformGroup>
                                </Grid.LayoutTransform>
                                <Ellipse x:Name="circle" Stroke="DarkGray" HorizontalAlignment="Center" VerticalAlignment="Center" Width="19" Height="19"/>
                                <Path x:Name="arrow" Stroke="#666" StrokeThickness="2" HorizontalAlignment="Center" VerticalAlignment="Center" SnapsToDevicePixels="false" Data="M 1,1.5 L 4.5,5 L 8,1.5"/>
                            </Grid>
                            <ContentPresenter HorizontalAlignment="Left" Margin="4,0,0,0" VerticalAlignment="Center" SnapsToDevicePixels="True" Grid.Column="1" RecognizesAccessKey="True"/>
                        </Grid>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsChecked" Value="true">
                            <Setter Property="Data" TargetName="arrow" Value="M 1,4.5  L 4.5,1  L 8,4.5"/>
                        </Trigger>
                        <Trigger Property="IsMouseOver" Value="true">
                            <Setter Property="Stroke" TargetName="circle" Value="#FF3C7FB1"/>
                            <Setter Property="Stroke" TargetName="arrow" Value="#222"/>
                        </Trigger>
                        <Trigger Property="IsPressed" Value="true">
                            <Setter Property="Stroke" TargetName="circle" Value="#FF526C7B"/>
                            <Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
                            <Setter Property="Stroke" TargetName="arrow" Value="#FF003366"/>
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <Style x:Key="ExpanderLeftHeaderStyle" TargetType="{x:Type ToggleButton}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ToggleButton}">
                    <Border Padding="{TemplateBinding Padding}">
                        <Grid SnapsToDevicePixels="False" Background="Transparent">
                            <Grid.RowDefinitions>
                                <RowDefinition Height="19"/>
                                <RowDefinition Height="*"/>
                            </Grid.RowDefinitions>
                            <Grid>
                                <Grid.LayoutTransform>
                                    <TransformGroup>
                                        <TransformGroup.Children>
                                            <TransformCollection>
                                                <RotateTransform Angle="90"/>
                                            </TransformCollection>
                                        </TransformGroup.Children>
                                    </TransformGroup>
                                </Grid.LayoutTransform>
                                <Ellipse x:Name="circle" Stroke="DarkGray" HorizontalAlignment="Center" VerticalAlignment="Center" Width="19" Height="19"/>
                                <Path x:Name="arrow" Stroke="#666" StrokeThickness="2" HorizontalAlignment="Center" VerticalAlignment="Center" SnapsToDevicePixels="false" Data="M 1,1.5 L 4.5,5 L 8,1.5"/>
                            </Grid>
                            <ContentPresenter HorizontalAlignment="Center" Margin="0,4,0,0" VerticalAlignment="Top" SnapsToDevicePixels="True" Grid.Row="1" RecognizesAccessKey="True"/>
                        </Grid>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsChecked" Value="true">
                            <Setter Property="Data" TargetName="arrow" Value="M 1,4.5  L 4.5,1  L 8,4.5"/>
                        </Trigger>
                        <Trigger Property="IsMouseOver" Value="true">
                            <Setter Property="Stroke" TargetName="circle" Value="#FF3C7FB1"/>
                            <Setter Property="Stroke" TargetName="arrow" Value="#222"/>
                        </Trigger>
                        <Trigger Property="IsPressed" Value="true">
                            <Setter Property="Stroke" TargetName="circle" Value="#FF526C7B"/>
                            <Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
                            <Setter Property="Stroke" TargetName="arrow" Value="#FF003366"/>
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <Style x:Key="ExpanderHeaderFocusVisual">
        <Setter Property="Control.Template">
            <Setter.Value>
                <ControlTemplate>
                    <Border>
                        <Rectangle Stroke="Black" StrokeDashArray="1 2" StrokeThickness="1" Margin="0" SnapsToDevicePixels="true"/>
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <Style x:Key="ExpanderDownHeaderStyle" TargetType="{x:Type ToggleButton}">
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ToggleButton}">
                    <Border Padding="{TemplateBinding Padding}">
                        <Grid SnapsToDevicePixels="False" Background="Transparent">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="19"/>
                                <ColumnDefinition Width="*"/>
                            </Grid.ColumnDefinitions>
                            <Ellipse x:Name="circle" Stroke="DarkGray" HorizontalAlignment="Center" VerticalAlignment="Center" Width="19" Height="19"/>
                            <Path x:Name="arrow" Stroke="#666" StrokeThickness="2" HorizontalAlignment="Center" VerticalAlignment="Center" SnapsToDevicePixels="false" Data="M 1,1.5 L 4.5,5 L 8,1.5"/>
                            <ContentPresenter HorizontalAlignment="Stretch" Margin="4,0,0,0" VerticalAlignment="Center" SnapsToDevicePixels="True" Grid.Column="1" RecognizesAccessKey="True"/>
                        </Grid>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsChecked" Value="true">
                            <Setter Property="Data" TargetName="arrow" Value="M 1,4.5  L 4.5,1  L 8,4.5"/>
                        </Trigger>
                        <Trigger Property="IsMouseOver" Value="true">
                            <Setter Property="Stroke" TargetName="circle" Value="#FF3C7FB1"/>
                            <Setter Property="Stroke" TargetName="arrow" Value="#222"/>
                        </Trigger>
                        <Trigger Property="IsPressed" Value="true">
                            <Setter Property="Stroke" TargetName="circle" Value="#FF526C7B"/>
                            <Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
                            <Setter Property="Stroke" TargetName="arrow" Value="#FF003366"/>
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
    <Style x:Key="ExpanderStyle1" TargetType="{x:Type Expander}">
        <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
        <Setter Property="Background" Value="Transparent"/>
        <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
        <Setter Property="VerticalContentAlignment" Value="Stretch"/>
        <Setter Property="BorderBrush" Value="Transparent"/>
        <Setter Property="BorderThickness" Value="1"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Expander}">
                    <Border SnapsToDevicePixels="true" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="3">
                        <DockPanel>
                            <ToggleButton x:Name="HeaderSite" FocusVisualStyle="{StaticResource ExpanderHeaderFocusVisual}" Margin="1" MinHeight="0" MinWidth="0" Style="{StaticResource ExpanderDownHeaderStyle}" Content="{TemplateBinding Header}" ContentTemplate="{TemplateBinding HeaderTemplate}" ContentTemplateSelector="{TemplateBinding HeaderTemplateSelector}" FontFamily="{TemplateBinding FontFamily}" FontSize="{TemplateBinding FontSize}" FontStretch="{TemplateBinding FontStretch}" FontStyle="{TemplateBinding FontStyle}" FontWeight="{TemplateBinding FontWeight}" Foreground="{TemplateBinding Foreground}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" DockPanel.Dock="Top" IsChecked="{Binding IsExpanded, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"/>
                            <ContentPresenter x:Name="ExpandSite" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}" Focusable="false" Visibility="Collapsed" DockPanel.Dock="Bottom"/>
                        </DockPanel>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsExpanded" Value="true">
                            <Setter Property="Visibility" TargetName="ExpandSite" Value="Visible"/>
                        </Trigger>
                        <Trigger Property="ExpandDirection" Value="Right">
                            <Setter Property="DockPanel.Dock" TargetName="ExpandSite" Value="Right"/>
                            <Setter Property="DockPanel.Dock" TargetName="HeaderSite" Value="Left"/>
                            <Setter Property="Style" TargetName="HeaderSite" Value="{StaticResource ExpanderRightHeaderStyle}"/>
                        </Trigger>
                        <Trigger Property="ExpandDirection" Value="Up">
                            <Setter Property="DockPanel.Dock" TargetName="ExpandSite" Value="Top"/>
                            <Setter Property="DockPanel.Dock" TargetName="HeaderSite" Value="Bottom"/>
                            <Setter Property="Style" TargetName="HeaderSite" Value="{StaticResource ExpanderUpHeaderStyle}"/>
                        </Trigger>
                        <Trigger Property="ExpandDirection" Value="Left">
                            <Setter Property="DockPanel.Dock" TargetName="ExpandSite" Value="Left"/>
                            <Setter Property="DockPanel.Dock" TargetName="HeaderSite" Value="Right"/>
                            <Setter Property="Style" TargetName="HeaderSite" Value="{StaticResource ExpanderLeftHeaderStyle}"/>
                        </Trigger>
                        <Trigger Property="IsEnabled" Value="false">
                            <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</Window.Resources>

  <Expander x:Name="ImageExpander" Style="{DynamicResource ExpanderStyle1}">

    <Expander.Header>

        <Grid >
            <Grid.ColumnDefinitions>
                <ColumnDefinition  />
                <ColumnDefinition Width="auto" />
            </Grid.ColumnDefinitions>
            <Label Padding="0" >My Header Text</Label>
            <Image Grid.Column="1" Margin="0" 
               Source="accounting-pic.jpg" Width="18" />
        </Grid>
    </Expander.Header>
</Expander>