Question

我正在尝试创建ComboBox作为DataGrid的自定义PopUp。我覆盖了标准Template，但当我将ItemsHost设置为DataGrid（IsItemsHost="True"）时，我得到The member "IsItemsHost" is not recognized or is not accesible（正如预期的那样）

<Popup Name="Popup"
       Placement="Bottom"
       IsOpen="{TemplateBinding IsDropDownOpen}"
       AllowsTransparency="True"
       Focusable="False"
       PopupAnimation="Slide">
       <Grid Name="DropDown"
             SnapsToDevicePixels="True"               
             MinWidth="{TemplateBinding ActualWidth}"
             MaxHeight="{TemplateBinding MaxDropDownHeight}">
            <Border x:Name="DropDownBorder"
                    Background="White"
                    BorderThickness="1"
                    BorderBrush="LightGray"/>
                    <ScrollViewer Margin="1,2" SnapsToDevicePixels="True">
                          <DataGrid IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained" />
                    </ScrollViewer>
       </Grid>
</Popup>

我该如何实现？

进度：

根据Microsoft：

为ComboBox创建ControlTemplate时，您的模板可能在ScrollViewer中包含ItemsPresenter。（ItemsPresenter显示ComboBox中的每个项目; ScrollViewer允许在控件内滚动）。如果ItemsPresenter不是ScrollViewer的直接子项，则必须为ItemsPresenter指定名称ItemsPresenter。

所以这是有效的（当我有一个完整的解决方案时，我会将其添加为答案）：

<Popup Name="Popup"
       Placement="Bottom"
       IsOpen="{TemplateBinding IsDropDownOpen}"
       AllowsTransparency="True"
       Focusable="False"
       PopupAnimation="Slide">
    <Grid Name="DropDown"
          SnapsToDevicePixels="True"               
          MinWidth="{TemplateBinding ActualWidth}"
          MaxHeight="{TemplateBinding MaxDropDownHeight}">
         <Border x:Name="DropDownBorder"
                 Background="White"
                 BorderThickness="1"
                 BorderBrush="LightGray"/>
             <ScrollViewer Margin="1,2" SnapsToDevicePixels="True">
                   <StackPanel Orientation="Vertical" >
                        <DataGrid x:Name="ItemsPresenter" ItemsSource="{TemplateBinding ItemsSource}" KeyboardNavigation.DirectionalNavigation="Contained"></DataGrid>
                        <Border Height="10" Background="Red" />
                   </StackPanel>
             </ScrollViewer>
       </Grid>
</Popup>

Answer 1

使用DataGrid（StackPanel / Grid等）代替Panel。

由于IsItemsHost属性是Panel的成员，并且它不是attached property，因此您无法将其与DataGrid一起使用。

Panel.IsItemsHost Property

现在，如果您希望自己的项目显示在DataGrid中，那么您必须使用ItemsSource DataGrid指向Items的{{1}}集合。 ComboBox。

如果您在ComboBoxItem中直接使用ComboBox而没有任何外部DataSource，则下面的代码将有效：

<DataGrid ItemsSource="{Binding Items, RelativeSource={RelativeSource TemplatedParent}}">
    <DataGrid.Columns>
        <DataGridTemplateColumn>
            <DataGridTemplateColumn.CellTemplate>
                <DataTemplate>
                    <ComboBoxItem Content="{Binding Content}"/>
                </DataTemplate>
            </DataGridTemplateColumn.CellTemplate>
        </DataGridTemplateColumn>
    </DataGrid.Columns>
</DataGrid>

如果您使用的是外部数据源，请将{Binding Content}替换为{Binding someproperty}。

我完全按照您的代码制作了一个工作样本，并且工作正常。

Answer 2

我设法得到了我想要的风格（我的目的是为分页创建一个ComboBox）：

        <Style x:Key="DataGridComboBoxStyle" TargetType="{x:Type ComboBox}">
        <Setter Property="Foreground" Value="DimGray" />
        <Setter Property="BorderBrush" Value="LightGray" />
        <Setter Property="Background" Value="White" />
        <Setter Property="SnapsToDevicePixels" Value="True"/>
        <Setter Property="OverridesDefaultStyle" Value="True"/>
        <Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
        <Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
        <Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
        <Setter Property="FontSize" Value="12" />
        <Setter Property="FontFamily" Value="Tahoma, Verdana" />
        <Setter Property="Height" Value="25" />
        <Setter Property="HorizontalContentAlignment" Value="Left" />
        <Setter Property="MaxDropDownHeight" Value="250" />
        <Setter Property="StaysOpenOnEdit" Value="True" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="ComboBox">
                    <Grid>
                        <ToggleButton Name="ToggleButton"
                                      BorderBrush="{TemplateBinding BorderBrush}"
                                      Background="{TemplateBinding Background}"
                                      Foreground="{TemplateBinding Foreground}"
                                      Style="{StaticResource ComboBoxToggleButton}"
                                      Grid.Column="2"
                                      Focusable="false"
                                      IsChecked="{Binding Path=IsDropDownOpen,Mode=TwoWay,RelativeSource={RelativeSource TemplatedParent}}"
                                      ClickMode="Press">
                        </ToggleButton>
                        <ContentPresenter Name="ContentSite"
                                          IsHitTestVisible="False"
                                          Content="{Binding ElementName=ItemsPresenter, Path=SelectedItem}"
                                          ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
                                          ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}"
                                          Margin="10,3,30,3"
                                          VerticalAlignment="Center"
                                          HorizontalAlignment="Center" />
                        <TextBox x:Name="PART_EditableTextBox"
                                 Style="{x:Null}"
                                 SelectionBrush="Transparent"
                                 Template="{StaticResource ComboBoxTextBox}"
                                 Text="{Binding ElementName=ItemsPresenter, Path=SelectedItem}"
                                 Foreground="{TemplateBinding Foreground}"
                                 FontFamily="{TemplateBinding FontFamily}"
                                 FontSize="{TemplateBinding FontSize}"
                                 FontWeight="{TemplateBinding FontWeight}"
                                 HorizontalAlignment="Stretch"
                                 HorizontalContentAlignment="Left"
                                 VerticalAlignment="Stretch"
                                 VerticalContentAlignment="Center"
                                 Background="Transparent"
                                 Margin="3,3,23,3"
                                 Focusable="True"                               
                                 Visibility="Hidden"
                                 IsReadOnly="{TemplateBinding IsReadOnly}"/>
                        <Popup Name="Popup"
                               Placement="Bottom"
                               IsOpen="{TemplateBinding IsDropDownOpen}"
                               AllowsTransparency="True"
                               Focusable="False"
                               PopupAnimation="Slide">
                            <Grid Name="DropDown"
                                  SnapsToDevicePixels="True"               
                                  MinWidth="{TemplateBinding ActualWidth}"
                                  MaxHeight="{TemplateBinding MaxDropDownHeight}">
                                <Border x:Name="DropDownBorder"
                                        Background="White"
                                        BorderThickness="1"
                                        BorderBrush="LightGray"/>
                                <ScrollViewer Margin="1,2" SnapsToDevicePixels="True" VerticalScrollBarVisibility="Disabled" HorizontalScrollBarVisibility="Disabled">
                                    <StackPanel Orientation="Vertical" >
                                        <DataGrid x:Name="ItemsPresenter" 
                                                  IsReadOnly="True"
                                                  ScrollViewer.CanContentScroll="True" 
                                                  ScrollViewer.HorizontalScrollBarVisibility="Auto" 
                                                  ScrollViewer.VerticalScrollBarVisibility="Auto" 
                                                  ItemsSource="{TemplateBinding ItemsSource}" 
                                                  BorderBrush="Transparent" 
                                                  RowHeaderWidth="0"
                                                  RowHeight="20"
                                                  ColumnWidth="*"
                                                  HeadersVisibility="None"
                                                  GridLinesVisibility="None"
                                                  KeyboardNavigation.DirectionalNavigation="Contained">
                                        </DataGrid>
                                        <Border BorderBrush="LightGray" BorderThickness="0, 1, 0, 0">
                                            <DockPanel LastChildFill="True" Background="White" Margin="5">
                                                <Button Style="{StaticResource DataGridPagingButtonStyle}" DockPanel.Dock="Left" >
                                                    <Button.Content>
                                                        <UniformGrid Margin="1">
                                                            <Path Height="20" Width="20" Stroke="DarkGray" Stretch="Uniform" StrokeThickness="1" Data="M 4,1  L 1,4  L 4,7" />
                                                        </UniformGrid> 
                                                    </Button.Content>
                                                </Button>
                                                <Button Style="{StaticResource DataGridPagingButtonStyle}" DockPanel.Dock="Right">
                                                    <Button.Content>
                                                        <UniformGrid Margin="1">
                                                            <Path Height="20" Width="20" Stroke="DarkGray" Stretch="Uniform" StrokeThickness="1" Data="M1,1 L4,4 1,7" />
                                                        </UniformGrid>
                                                    </Button.Content>
                                                </Button>
                                                <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" DockPanel.Dock="Left">
                                                    <TextBlock FontFamily="Tahoma, Verdana" FontSize="11" Foreground="DimGray" VerticalAlignment="Center" Padding="0, 0, 5, 2" Text="Page" />
                                                    <TextBox BorderBrush="LightGray" FontFamily="Tahoma, Verdana" FontSize="11" Foreground="DimGray" Height="20" Width="20" HorizontalContentAlignment="Center" Text="1" />
                                                    <TextBlock FontFamily="Tahoma, Verdana" FontSize="11" Foreground="DimGray" VerticalAlignment="Center" Padding="5, 0, 5, 2" Text="to" />
                                                    <TextBlock FontFamily="Tahoma, Verdana" FontSize="11" Foreground="DimGray" VerticalAlignment="Center" Padding="0, 0, 0, 2" Text="(bind pages)" />
                                                </StackPanel>
                                            </DockPanel>
                                        </Border>
                                    </StackPanel>
                                </ScrollViewer>
                            </Grid>
                        </Popup>
                    </Grid>
                    <ControlTemplate.Triggers>
                        <!-- Triggers -->
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

带有DataGrid PopUp的ComboBox

2 个答案: