Question

使用MVVM的MVVM方法，我有一个名为SubButton的视图模型类。它的风格如下：

<!-- SubNavButton Appearance -->
<ControlTemplate x:Key="SubNavButton" TargetType="{x:Type RadioButton}">
    <Grid Margin="5,5">
        <Rectangle x:Name="rectBackground" Fill="DimGray" Stroke="#FF000000" Width="150" Height="40" StrokeThickness="1"/>
        <TextBlock x:Name="txtContent" HorizontalAlignment="Center" VerticalAlignment="Center" FontFamily="Arial" FontSize="16">
    <ContentPresenter />
        </TextBlock>
    </Grid>
    <ControlTemplate.Triggers>
        <Trigger Property="IsMouseOver" Value="True">
            <Setter Property="Fill" TargetName="rectBackground" Value="Red"/>
        </Trigger>
        <Trigger Property="IsChecked" Value="True">
            <Setter Property="Fill" TargetName="rectBackground" Value="Pink"/>
        </Trigger>
    </ControlTemplate.Triggers>
</ControlTemplate>

<!-- SubButton data template -->
<DataTemplate DataType="{x:Type VM:SubButton}">
    <RadioButton 
        Template="{StaticResource SubNavButton}"
        Content="{Binding TempText}"
        Command="{Binding SubFrameChanger.Command}"
        CommandParameter="{Binding Key}"
        GroupName="{Binding MenuGroup}"
        V:CreateCommandBinding.Command="{Binding SubFrameChanger}" />
    <DataTemplate.Triggers>
        <!-- This trigger doesn't work -->
        <DataTrigger Binding="{Binding Path=Selected}" Value="True">
            <Setter TargetName="rectBackground" Property="Fill" Value="Green"/>
        </DataTrigger>
    </DataTemplate.Triggers>
</DataTemplate>

DataTrigger不起作用。 Selected是SubButton类上的常规.Net属性。我收到编译错误，因为编译器无法确定rectBackground目标的来源。它是ControlTemplate的一部分，我不知道该怎么说呢？关于DataContext？

的一些事情

Answer 1

你想要的是不可能的。 WPF与NameScopes一起使用，名称rectBackground超出了DataTemplate的范围。原始名称rectBackground将仅位于原始ControlTemplate内的范围内。这很幸运，因为否则您将无法在整个应用程序中使用重复的名称。你可以做的是通过TemplateBinding将rectBackground的Fill属性绑定到RadioButton的Background属性。当您在代码中的任何其他地方更改RadioButton的背景时，rectBackground会将此Brush作为其填充。我稍微修改了你的代码来说明问题。使用DataTemplate将其更改为您的模型很容易。

    <Window.Resources>
        <ControlTemplate x:Key="SubNavButton" TargetType="RadioButton">
            <Grid Margin="5,5">
                <Rectangle x:Name="rectBackground"
                       Fill="{TemplateBinding Background}" 
                       Stroke="#FF000000" Width="150" Height="40"
                       StrokeThickness="1"/>
                <TextBlock x:Name="txtContent" HorizontalAlignment="Center"
                       VerticalAlignment="Center"
                       FontFamily="Arial" FontSize="16">
                <ContentPresenter />
                </TextBlock>
            </Grid>
            <ControlTemplate.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter Property="Fill"
                        TargetName="rectBackground" Value="Red"/>
                </Trigger>
                <Trigger Property="IsChecked" Value="True">
                    <Setter Property="Fill" 
                        TargetName="rectBackground" Value="Pink"/>
                </Trigger>
            </ControlTemplate.Triggers>
        </ControlTemplate>
        <!-- The Style simulates the same behavior as the DataTemplate-->
        <Style TargetType="RadioButton">
            <Setter Property="Template" 
                Value="{StaticResource SubNavButton}"/>
            <Style.Triggers>
                <Trigger Property="IsFocused" Value="True">
                    <Setter Property="Background" Value="Green"/>
                </Trigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>
    <StackPanel>
       <RadioButton>one</RadioButton>
       <RadioButton>two</RadioButton>
    </StackPanel>

WPF：从DataTemplate修改ControlTemplate属性？

1 个答案: