如何在按钮模板之外更改图像源

Question

我创建了此按钮模板

<ControlTemplate x:Key="RoundedButton" TargetType="{x:Type Button}">
    <Border x:Name="buttonBorder"
            Background="{TemplateBinding Background}"
            BorderBrush="{TemplateBinding BorderBrush}"
            TextBlock.Foreground="{TemplateBinding Foreground}"
            Height="{TemplateBinding Height}"
            Width="{TemplateBinding Width}"
            CornerRadius="{Binding ElementName=buttonImage, Path=RenderSize}">
        <Grid>
            <Image x:Name="buttonImage" Source="Images/send.png"/>
        </Grid>
    </Border>

    <ControlTemplate.Triggers>
        <Trigger Property="IsMouseOver" Value="True">
            <Setter TargetName="buttonImage" Property="Opacity" Value="0.8"/>
        </Trigger>
        <Trigger Property="IsPressed" Value="True">
            <Setter TargetName="buttonBorder" Property="BorderThickness" Value="1"/>
        </Trigger>
    </ControlTemplate.Triggers>
</ControlTemplate>

我想像其他属性一样在MainWindow.xaml中更改Image Source。 示例：我可以在MainWindow.xaml中更改Background，因为我给出了 Background =“ {TemplateBinding Background}” ，但是在Image标签中不起作用。如果您有帮助，我将不胜感激