Question

我有一个绑定到类的WPF ListBox。如下

   public class MyClass
   {
     public string Name{ get; set; }
     public string Gender{ get; set; }
   }

  ObservableCollection<MyClass> myData= new ObservableCollection<MyTable>();
  myClassList.ItemsSource = myData;

我将XAML视为：

  <DataTemplate x:Key="userData">
    <Grid HorizontalAlignment="Stretch" Margin="3,0,3,0" Height="60">
      <Grid.ColumnDefinitions>
        <ColumnDefinition Width="*"/>
        <ColumnDefinition Width="*"/>
      </Grid.ColumnDefinitions>

      <wpfgeneralcontrols:TextControl Grid.Column="0" Grid.Row="0" Text="{Binding Path=Name}" Style="{StaticResource SmallTextControlStyle}"
                 TextAlignment="Left" Margin="0"/>

      <wpfgeneralcontrols:TextControl Grid.Column="1" Grid.Row="0" Text="{Binding Path=Gender}" Style="{StaticResource SmallTextControlStyle}"
                 TextAlignment="Left" Margin="0"/>
    </Grid>
  </DataTemplate>


  <ListView Name="PatientsList" Background="Transparent"  BorderThickness="0"
           Width="700" HorizontalAlignment="Center"
           ItemTemplate="{StaticResource userData}"
           ScrollViewer.VerticalScrollBarVisibility ="Visible" />

如何仅设置ListBox的第一项（不是所选项目）的前景色？我已经看到了一些关于接近这个的想法，但无法使其适应设置列表框中第一个项目的前景色。

Answer 1

您不能在纯XAML中执行此操作 - XAML是标记语言而不是编程语言 - 但您可以处理根Loaded的{{1}}事件在您的Grid中以编程方式：

ItemTemplate

<DataTemplate x:Key="userData">
    <Grid HorizontalAlignment="Stretch" Margin="3,0,3,0" Height="60"
          Loaded="Grid_Loaded">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>

        <TextBlock Grid.Column="0" Grid.Row="0" Text="{Binding Path=Name}"
                   TextAlignment="Left" Margin="0"/>

        <TextBlock Grid.Column="1" Grid.Row="0" Text="{Binding Path=Gender}"
                   TextAlignment="Left" Margin="0"/>
    </Grid>
</DataTemplate>

我认为您的自定义int n = 0; private void Grid_Loaded(object sender, RoutedEventArgs e) { if (n++ == 0) { Grid grid = sender as Grid; foreach (var tb in grid.Children.OfType<TextBlock>()) tb.Foreground = System.Windows.Media.Brushes.Red; grid.Loaded -= Grid_Loaded; } }具有TextControl属性。在上面的示例代码中，我使用了Foreground。

这并没有打破MVVM模式。在视图中实现与视图相关的逻辑是完全正确的。

Answer 2

如果您的商品不为空，则可以使用PreviousData来检测第一项。

<DataTemplate x:Key="userData">
    <TextBlock Text="{Binding Path=Name}"/>
</DataTemplate>

<ListView ItemTemplate="{StaticResource userData}" ItemsSource="{Binding MyItems}">
    <ListView.ItemContainerStyle>
        <Style TargetType="{x:Type ListViewItem}">
            <Style.Triggers>
                <DataTrigger Binding="{Binding RelativeSource={RelativeSource PreviousData}}" Value="{x:Null}">
                    <Setter Property="Background" Value="Red" />
               </DataTrigger>
            </Style.Triggers>
        </Style>
    </ListView.ItemContainerStyle>
</ListView>

WPF列表框项目：设置第一项的前景色

2 个答案: