Wpf Combobox: Different Template in Textbox and Drop-Downlist

WPF Combobox: Different template in textbox and drop-downlist

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.

Different template for items in ComboBox's drop-down list and for selected item

The selected item (in the ComboBox itself, not the dropdown) is not inside a ComboBoxItem so you can do something like this:

<ComboBox.ItemTemplate>
<DataTemplate>
<ContentControl Content="{Binding}">
<ContentControl.Style>
<Style TargetType="{x:Type ContentControl}">
<!-- Complex default template -->
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<Image Source="{Binding XPath=media:thumbnail/@url}" Width="100" Height="100" />
</DataTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<!-- Simple selection box template -->
<DataTrigger
Binding="{Binding RelativeSource={RelativeSource AncestorType=ComboBoxItem}}"
Value="{x:Null}">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<TextBlock Text="{Binding XPath=title}" />
</DataTemplate>
</Setter.Value>
</Setter>
</DataTrigger>
</Style.Triggers>
</Style>
</ContentControl.Style>
</ContentControl>
</DataTemplate>
</ComboBox.ItemTemplate>

(Edit: Note that the binding in the for the selection box will throw errors because the RelativeSource is not found. There are various options of circumventing this, one being a custom value converter that returns true or false depending on whether the ancestor exists (manual tree walking).)

WPF: How to customize SelectionBoxItem in ComboBox

I would do it like this:

<Window.Resources>

<DataTemplate x:Key="NormalItemTemplate" ...>
...
</DataTemplate>

<DataTemplate x:Key="SelectionBoxTemplate" ...>
...
</DataTemplate>

<DataTemplate x:Key="CombinedTemplate">
<ContentPresenter x:Name="Presenter"
Content="{Binding}"
ContentTemplate="{StaticResource NormalItemTemplate}" />
<DataTemplate.Triggers>
<DataTrigger
Binding="{Binding RelativeSource={RelativeSource FindAncestor,ComboBoxItem,1}}"
Value="{x:Null}">
<Setter TargetName="Presenter" Property="ContentTemplate"
Value="{StaticResource SelectionBoxTemplate}" />
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>

</Window.Resources>

...

<ComboBox
ItemTemplate="{StaticResource CombinedTemplate}"
ItemsSource="..."
... />

The reason this works is that CombinedTemplate normally just uses NormalItemTemplate to present its data, but if there is no ComboBoxItem ancestor it assumes it is in the selection box so it uses SelectionBoxTemplate.

Note that the three DataTemplates could be included in any level of ResourceDictionary (not just at the Window level) or even directly within the ComboBox, depending on your preference.

wpf combobox with custom itemtemplate text

Try setting SelectionBoxItemTemplate with a TextBlock.
Appears that SelectionBoxItemTemplate is read-only. So another approach is to override ItemContainerStyle.Template. Example

Can editable WPF ComboBox text be formatted differently to the formatting of the items in the drop-down?

This should work:

<ComboBox TextSearch.TextPath="Other" IsEditable="True" Height="50" ItemsSource="{Binding FooItems}"/>

How to display a different value for dropdown list values/selected item in a WPF ComboBox?

Update 2011-11-14

I recently came upon the same requirement again and I wasn't very happy with the solution I posted below. Here is a nicer way to get the same behavior without re-templating the ComboBoxItem. It uses a DataTemplateSelector

First, specify the regular DataTemplate, the dropdown DataTemplate and the ComboBoxItemTemplateSelector in the resources for the ComboBox. Then reference the ComboBoxItemTemplateSelector as a DynamicResource for ItemTemplateSelector

<ComboBox ...
ItemTemplateSelector="{DynamicResource itemTemplateSelector}">
<ComboBox.Resources>
<DataTemplate x:Key="selectedTemplate">
<TextBlock Text="{Binding Path=ShortDescription}"/>
</DataTemplate>
<DataTemplate x:Key="dropDownTemplate">
<TextBlock Text="{Binding Path=FullDescription}"/>
</DataTemplate>
<local:ComboBoxItemTemplateSelector
x:Key="itemTemplateSelector"
SelectedTemplate="{StaticResource selectedTemplate}"
DropDownTemplate="{StaticResource dropDownTemplate}"/>
</ComboBox.Resources>
</ComboBox>

ComboBoxItemTemplateSelector checks if the container is the child of a ComboBoxItem, if it is, then we are dealing with a dropdown item, otherwise it is the item in the ComboBox.

public class ComboBoxItemTemplateSelector : DataTemplateSelector
{
public DataTemplate DropDownTemplate
{
get;
set;
}
public DataTemplate SelectedTemplate
{
get;
set;
}
public override DataTemplate SelectTemplate(object item, DependencyObject container)
{
ComboBoxItem comboBoxItem = VisualTreeHelpers.GetVisualParent<ComboBoxItem>(container);
if (comboBoxItem != null)
{
return DropDownTemplate;
}
return SelectedTemplate;
}
}

GetVisualParent

public static T GetVisualParent<T>(object childObject) where T : Visual
{
DependencyObject child = childObject as DependencyObject;
while ((child != null) && !(child is T))
{
child = VisualTreeHelper.GetParent(child);
}
return child as T;
}

Old solution, requires re-templating of ComboBoxItem

<SolidColorBrush x:Key="SelectedBackgroundBrush" Color="#DDD" />
<SolidColorBrush x:Key="DisabledForegroundBrush" Color="#888" />

<ControlTemplate x:Key="FullDescriptionTemplate" TargetType="ComboBoxItem">
<Border Name="Border" Padding="2" SnapsToDevicePixels="true">
<StackPanel>
<TextBlock Text="{Binding Path=FullDescription}"/>
</StackPanel>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsHighlighted" Value="true">
<Setter TargetName="Border" Property="Background" Value="{StaticResource SelectedBackgroundBrush}"/>
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Foreground" Value="{StaticResource DisabledForegroundBrush}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>

<ComboBox Name="c_comboBox" ItemsSource="{Binding}">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=ShortDescription}"/>
</DataTemplate>
</ComboBox.ItemTemplate>
<ComboBox.ItemContainerStyle>
<Style TargetType="{x:Type ComboBoxItem}">
<Setter Property="Template" Value="{StaticResource FullDescriptionTemplate}" />
</Style>
</ComboBox.ItemContainerStyle>
</ComboBox>

This results in the following behavior

alt text



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