如何在WPF中隐藏组合框的项

问题描述

有没有办法在WPF中隐藏组合框的项？ 在我的用户控件中，有一个带有CheckBox-Items绑定到ObservableCollection的ListBox和一个带有Combobox的DataRid。

<ListBox x:Name="AvailableAttributes" Grid.Row="0" Grid.Column="2" SelectionMode="Single" >
    <ListBox.ItemContainerStyle>
        <Style TargetType="{x:Type ListBoxItem}">
            <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=OneWay}"/>
        </Style>
    </ListBox.ItemContainerStyle>

    <ListBox.ItemTemplate>
        <DataTemplate>
            <CheckBox Content="{Binding Name}" IsChecked="{Binding IsSelected}"/>
        </DataTemplate>
    </ListBox.ItemTemplate>
</ListBox>

... 

<DataGrid Name="datagrid" AutoGenerateColumns="False" >
    <DataGrid.Columns>
        <DataGridTextColumn Binding="{Binding Name}" />
            <DataGridComboBoxColumn 
                SelectedValueBinding="{Binding CBID}" 
                DisplayMemberPath="Name" 
                SelectedValuePath="ID">

                <DataGridComboBoxColumn.ElementStyle>
                    <Style TargetType="{x:Type ComboBox}">
                        <Setter Property="ItemsSource" 
                            Value="{Binding Path=CBItems, RelativeSource={RelativeSource AncestorType={x:Type UserControl}}}" />
                    </Style>
                </DataGridComboBoxColumn.ElementStyle>
                <DataGridComboBoxColumn.EditingElementStyle>
                    <Style TargetType="{x:Type ComboBox}">
                        <Setter Property="ItemsSource" 
                            Value="{Binding Path=CBItems, RelativeSource={RelativeSource AncestorType={x:Type UserControl}}}" />
                    </Style>
                </DataGridComboBoxColumn.EditingElementStyle>
            </DataGridComboBoxColumn>
        </DataGrid.Columns>
    </DataGrid>

我使用this solution管理组合框项，并添加了属性‘IsSelected’

public class GridItem
{
    public string Name { get; set; }
    public int CBID { get; set; }
}

public class CBItem
{
    public int ID { get; set; }
    public string Name { get; set; }
    public bool IsSelected { get; set; }
}

推荐答案

非常简单：只需给组合框项一个带有触发器的样式，根据ComboBoxItem的DataContext上的IsSelected的值设置IsSelected：

<Style TargetType="{x:Type ComboBox}" BasedOn="{StaticResource {x:Type ComboBox}}">
    <Setter Property="ItemsSource" 
        Value="{Binding Path=CBItems, RelativeSource={RelativeSource AncestorType={x:Type UserControl}}}" />
    <Setter Property="ItemContainerStyle">
        <Setter.Value>
            <Style TargetType="ComboBoxItem" BasedOn="{StaticResource {x:Type ComboBoxItem}}">
                <Style.Triggers>
                    <DataTrigger Binding="{Binding IsSelected}" Value="False">
                        <Setter Property="Visibility" Value="Collapsed" />
                    </DataTrigger>
                </Style.Triggers>
            </Style>
        </Setter.Value>
    </Setter>
</Style>