WPF Combobox: Different template in textbox and drop-downlist
This is my combo-box.
<ComboBox Height="45" HorizontalAlignment="Left" Margin="184,66,0,0" Name="ComboBox1" VerticalAlignment="Top" Width="216">
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Label Content="{Binding FullName}" Width="150" />
<Label Content="{Binding Title}" Width="100"/>
<Label Content="{Binding BranchName}" />
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
How can I change it so that only the FullName appears in the textbox portion of the combobox while all three columns still appear in the drop-down portion?
Solution 1:
Unfortunately, the SelectionBoxItemTemplate is a readonly property, so we have to do a bit more work. By doing the ItemTemplate to be how you want the item to appear when selected, you can edit the ItemContainerStyle to provide a ControlTemplate that includes the other fields you want to display.
<ComboBox Height="45" HorizontalAlignment="Left" Margin="184,66,0,0" Name="ComboBox1" VerticalAlignment="Top" Width="216">
<ComboBox.ItemTemplate>
<DataTemplate>
<Label Content="{Binding FullName}" Width="150" />
</DataTemplate>
</ComboBox.ItemTemplate>
<ComboBox.ItemContainerStyle>
<Style TargetType="{x:Type ComboBoxItem}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ComboBoxItem}">
<Border x:Name="Bd"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Background="{TemplateBinding Background}">
<StackPanel Orientation="Horizontal">
<ContentPresenter HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}" />
<Label Content="{Binding Title}" Width="100"/>
<Label Content="{Binding BranchName}" />
</StackPanel>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsHighlighted" Value="True">
<Setter TargetName="Bd" Property="Background" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}" />
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}" />
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ComboBox.ItemContainerStyle>
</ComboBox>
For the ComboBoxItem template, I just modified the default one, so it should be fully functional.
Solution 2:
If the ComboBox's IsEditable property is set to True, you can set the "TextSearch.TextPath" property of the ComboBox to the property name you want to show. So in your case:
<ComboBox IsEditable="True" TextSearch.TextPath="FullName" .../>
Solution 3:
Instead of using the read-only SelectionBoxItemTemplate property I created a new (attached, writable) property and used that one in my style. I also added a trigger to my style to not break all the comboboxes that are not using my new attached property...
Use it like this:
<ComboBox ItemsSource="{Binding ...}" SelectedItem="{Binding ..., Mode=TwoWay}">
<controls:ComboBoxSelectionBoxAltTemplateBehaviour.SelectionBoxAltTemplate>
<DataTemplate DataType="{x:Type ...}">
... Template for the selection box ...
</DataTemplate>
</controls:ComboBoxSelectionBoxAltTemplateBehaviour.SelectionBoxAltTemplate>
<ComboBox.ItemTemplate>
<DataTemplate DataType="{x:Type ...}">
... Template for the popup ...
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
You just have to add this class to your project:
public class ComboBoxSelectionBoxAltTemplateBehaviour
{
public static readonly DependencyProperty SelectionBoxAltTemplateProperty = DependencyProperty.RegisterAttached(
"SelectionBoxAltTemplate", typeof (DataTemplate), typeof (ComboBoxSelectionBoxAltTemplateBehaviour), new PropertyMetadata(default(DataTemplate)));
public static void SetSelectionBoxAltTemplate(DependencyObject element, DataTemplate value)
{
element.SetValue(SelectionBoxAltTemplateProperty, value);
}
public static DataTemplate GetSelectionBoxAltTemplate(DependencyObject element)
{
return (DataTemplate) element.GetValue(SelectionBoxAltTemplateProperty);
}
}
and change your ComboBox style to use the SelectionBoxAltTemplate attached property if set (or because I could not set a trigger to "not null", I set it back to the default SelectionBoxItemTemplate if the attached one is null):
The ContentPresenter inside the ControlTemplate of the ComboBox Style:
<ContentPresenter Content="{TemplateBinding SelectionBoxItem}" ContentTemplate="{TemplateBinding controls:ComboBoxSelectionBoxAltTemplateBehaviour.SelectionBoxAltTemplate}" />
And the Trigger to provide backwards compatibility to ComboBoxed without the attached Property:
<ControlTemplate.Triggers>
<Trigger Property="controls:ComboBoxSelectionBoxAltTemplateBehaviour.SelectionBoxAltTemplate" Value="{x:Null}">
<Setter Property="ContentTemplate" Value="{Binding SelectionBoxItemTemplate, RelativeSource={RelativeSource TemplatedParent}}" TargetName="ContentSite" />
</Trigger>
...
</ControlTemplate.Triggers>
Full Style:
<Style x:Key="{x:Type ComboBox}" TargetType="{x:Type ComboBox}">
<Setter Property="SnapsToDevicePixels" Value="true" />
<Setter Property="HorizontalContentAlignment" Value="Stretch" />
<Setter Property="VerticalContentAlignment" Value="Center" />
<Setter Property="FontSize" Value="12" />
<Setter Property="Background" Value="{StaticResource ComboBoxBackground}"/>
<Setter Property="BorderBrush" Value="{StaticResource ComboBoxBorder}"/>
<Setter Property="Margin" Value="6"/>
<Setter Property="Padding" Value="3,3,5,3"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ComboBox}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Border Name="Border" Grid.ColumnSpan="2" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}"/>
<ToggleButton Name="ToggleButton2" Focusable="False" IsChecked="{Binding Path=IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" ClickMode="Press" Grid.ColumnSpan="2" Background="Transparent"/>
<!-- Allows clicking anywhere on the combobox, not only the visible button on the right -->
<ToggleButton Focusable="false" Grid.Column="1" x:Name="ToggleButton" IsChecked="{Binding Path=IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" ClickMode="Press" Style="{StaticResource ComboBoxToggleButton}"/>
<ContentPresenter HorizontalAlignment="Left" Margin="{TemplateBinding Control.Padding}" x:Name="ContentSite" VerticalAlignment="Center" Content="{TemplateBinding SelectionBoxItem}" ContentTemplate="{TemplateBinding controls:ComboBoxSelectionBoxAltTemplateBehaviour.SelectionBoxAltTemplate}" ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}" IsHitTestVisible="False" />
<TextBox Visibility="Hidden" HorizontalAlignment="Left" Margin="{TemplateBinding Control.Padding}" x:Name="PART_EditableTextBox" Style="{x:Null}" VerticalAlignment="Center" Focusable="True" Background="Transparent" />
<Popup IsOpen="{TemplateBinding IsDropDownOpen}" Placement="Bottom" x:Name="Popup" Focusable="False" AllowsTransparency="True" PopupAnimation="Slide">
<Grid MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{TemplateBinding ActualWidth}" x:Name="DropDown" SnapsToDevicePixels="True">
<Border x:Name="DropDownBorder" Background="{StaticResource ComboBoxBackground}" BorderBrush="{StaticResource ComboBoxBorder}" BorderThickness="1" Padding="0,4">
<ScrollViewer SnapsToDevicePixels="True" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" CanContentScroll="True" Style="{x:Null}" >
<StackPanel IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained"/>
</ScrollViewer>
</Border>
</Grid>
</Popup>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="controls:ComboBoxSelectionBoxAltTemplateBehaviour.SelectionBoxAltTemplate" Value="{x:Null}">
<Setter Property="ContentTemplate" Value="{Binding SelectionBoxItemTemplate, RelativeSource={RelativeSource TemplatedParent}}" TargetName="ContentSite" />
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="MinHeight" Value="95" TargetName="DropDownBorder" />
</Trigger>
<Trigger Property="IsGrouping" Value="true">
<Setter Property="ScrollViewer.CanContentScroll" Value="false" />
</Trigger>
<Trigger Property="IsEditable" Value="true">
<Setter Property="IsTabStop" Value="false" />
<Setter Property="Visibility" Value="Visible" TargetName="PART_EditableTextBox" />
<Setter Property="Visibility" Value="Hidden" TargetName="ContentSite" />
</Trigger>
<Trigger Property="IsMouseOver" Value="true" SourceName="ToggleButton2">
<Setter Property="Background" Value="{StaticResource ComboBoxMouseOver}" />
</Trigger>
<Trigger Property="HasItems" Value="False">
<Setter Property="IsEnabled" Value="False"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
However this might not work with ItemTemplateSelctors, only with one single template - but you could easily add an attached property "SelectionBoxAltTemplateSelector" which provides the selector and passes that one to the style.
Solution 4:
There is a pretty good answer to your question here if you don't want to change the ComboBoxes style: https://stackoverflow.com/a/2277488/1070906
It uses a Trigger in the DataTemplate which looks if there is a ComboBoxItem somewhere above in the visual tree, which is not the case in the selection box.