I've been using design time XAML data for a few weeks now and it seems to work fine except for some cases such as the current one where I want a listbox to display items based on a collection view declared as a resource.
Basically I want to display a list of "Things" grouped by Category.
public class Thing
{
public string Category { get; set; }
public string Name { get; set; }
}
And then I expose this via a dummy class ListOfThings
public class ListOfThings
{
public string ListName { get; set; }
public ObservableCollection<Thing> Things { get; set; }
}
I have a dummy XAML file for the data as follows (XMLFile1.xaml)
<local:ListOfThings xmlns:local="clr-namespace:ListBoxGroupExample"
ListName="TheListOfThings">
<local:ListOfThings.Things>
<local:Thing Name="Item1" Category="Catagory1" />
<local:Thing Name="Item2" Category="Catagory1" />
<local:Thing Name="Item3" Category="Catagory2" />
</local:ListOfThings.Things>
In the window I have a listbox with a group style for an expander for each group
<Window x:Class="ListBoxGroupExample.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:local="clr-namespace:ListBoxGroupExample"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
Title="MainWindow"
Width="525"
Height="350"
d:DataContext="{d:DesignData Source=/DesignData/XMLFile1.xaml}"
mc:Ignorable="d">
<Window.Resources>
<CollectionViewSource x:Key="GroupedData" Source="{Binding Path=Things}">
<CollectionViewSource.GroupDescriptions>
<PropertyGroupDescription PropertyName="Category" />
</CollectionViewSource.GroupDescriptions>
</CollectionViewSource>
</Window.Resources>
<Grid>
<StackPanel>
<ListBox ItemsSource="{Binding Source={StaticResource GroupedData}}">
<ListBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding Path=Name}" />
</DataTemplate>
</ListBox.ItemTemplate>
<ListBox.GroupStyle>
<GroupStyle>
<GroupStyle.ContainerStyle>
<Style TargetType="{x:Type GroupItem}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type GroupItem}">
<Expander IsExpanded="True">
<Expander.Header>
<TextBlock FontWeight="Bold" Text="{Binding Path=Name}" />
</Expander.Header>
<ItemsPresenter Margin="5,0,0,0" />
</Expander>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</GroupStyle.ContainerStyle>
</GroupStyle>
</ListBox.GroupStyle>
</ListBox>
</StackPanel>
</Grid>
This works at run time (I create an instance of ListOfThings, populate the Observable collection to have the same structure as the XAML design data) but at design time I get nothing.
If I change the ItemSource to directly bind to the ObservableCollection of Things rather than the collection view, it works but of course I get no grouping.
ItemsSource="{Binding Path=Things}"
Am I misunderstanding something with static resources in that they are not available at design time? Hence why the binding to the collectionview does not render?
Or is the binding syntax to Source incorrect?
