WPF listbox empty datatemplate

Solution 1:

I've had some success with this code:

<Style TargetType="ListBox" x:Key="ListStyle" BasedOn="{StaticResource {x:Type ListBox}}">
    <Style.Triggers>
        <DataTrigger 
            Binding="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=Items.Count}" 
            Value="0"
            >
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate>
                        <TextBlock>No items to display</TextBlock>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </DataTrigger>
    </Style.Triggers>
</Style>

Solution 2:

Based on @Matt Hamilton's accepted answer, for reference, I created a variation which does not require the binding, as it uses the HasItems property of the ListBox to trigger the empty template:

<ListBox.Style>
    <Style x:Key="EmptyListStyle"
           TargetType="ListBox"
           BasedOn="{StaticResource {x:Type ListBox}}">
        <Style.Triggers>
            <!-- Use ListBox.HasItems instead of Binding -->
            <Trigger Property="HasItems" Value="False">
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate>
                            <TextBlock>No items to display</TextBlock>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Trigger>
        </Style.Triggers>
    </Style>
</ListBox.Style>

This allows the style to be used globally, without having to know the property name to which the list binds. I found it useful when binding to a CollectionViewSource defined in XAML.

I'm not aware of any drawbacks of this method, comments welcome if you should find any.