Specify ControlTemplate for ItemsControl.ItemContainerStyle

Travis Heseman picture Travis Heseman · Aug 22, 2010 · Viewed 37k times · Source

The following is similar to what I'm trying to accomplish. However, I get the error

Invalid PropertyDescriptor value.

on the Template Setter. I suspect it's because I didn't specify a TargetType for the Style; however, I don't know the container type for ItemsControl.

<ItemsControl>
    <ItemsControl.ItemContainerStyle>
        <Style>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate>
                        <StackPanel>
                            <TextBlock Text="Some Content Here" />
                            <ContentPresenter />
                            <Button Content="Edit" />
                        </StackPanel>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </ItemsControl.ItemContainerStyle>
    <!-- heterogenous controls -->
    <ItemsControl.Items> 
        <Button Content="Content 1" />
        <TextBox Text="Content 2" />
        <Label Content="Content 3" />
    </ItemsControl.Items>
</ItemsControl>

Answer

Quartermeister picture Quartermeister · Aug 22, 2010

You can qualify the property name with the type name:

<Setter Property="Control.Template">

The container for ItemsControl is normally a ContentPresenter, but if the child is a UIElement then it won't use a container. In this case, all of the children are Controls, so the ItemContainerStyle will apply to them directly. If you added an item other than a UIElement, that setter would set the Control.Template property on the ContentPresenter, which would succeed but have no effect.

Actually, it sounds like what you want is to wrap each child in a container, even if they are already a UIElement. To do that, you will have to use a subclass of ItemsControl. You could use an existing one like ListBox, or you could subclass ItemsControl and override GetContainerForItemOverride and IsItemItsOwnContainerOverride to wrap the items in your own container. You could wrap them in a ContentControl and then use that as the TargetType for the Style.

public class CustomItemsControl
    : ItemsControl
{
    protected override DependencyObject GetContainerForItemOverride()
    {
        return new ContentControl();
    }

    protected override bool IsItemItsOwnContainerOverride(object item)
    {
        // Even wrap other ContentControls
        return false;
    }
}

You will also need to set the TargetType on the ControlTemplate so that the ContentPresenter will bind to the Content property:

<ControlTemplate TargetType="ContentControl">