Simple grouping in ListBox

<Grid>
<Grid.Resources>
<XmlDataProvider x:Key="Company" XPath="/Company">
<x:XData>
<Company xmlns="">
<Person Name="Jack" Role="CEO"/>
<Person Name="Tim" Role="PL" />
<Person Name="Jil" Role="PL" />
<Person Name="Jimmy" Role="PM" />
<Person Name="Joy" Role="PM" />
<Person Name="Jim" Role="PL" />
<Person Name="Jack" Role="PM" />
</Company>
</x:XData>
</XmlDataProvider>

<DataTemplate x:Key="categoryTemplate">
<TextBlock Text="{Binding Path=Name}" FontWeight="Bold" Background="ForestGreen" Margin="0,5,0,0"/>
</DataTemplate>
<DataTemplate x:Key="template">
<TextBlock Text="{Binding XPath=@Name}"/>
</DataTemplate>

<CollectionViewSource x:Key="cvs" Source="{Binding Source={StaticResource Company},XPath=Person}">
<CollectionViewSource.GroupDescriptions>
<PropertyGroupDescription PropertyName="@Role"/>
</CollectionViewSource.GroupDescriptions>
</CollectionViewSource>
</Grid.Resources>


<ListBox Name="lst"
ItemTemplate="{StaticResource template}"
ItemsSource="{Binding Source={StaticResource cvs}}">
<ListBox.GroupStyle>
<GroupStyle HeaderTemplate="{StaticResource categoryTemplate}" />
</ListBox.GroupStyle>
</ListBox>
</Grid>

If you want to sort items in these groups please use SortDescriptions along with GroupDescriptions.For more details visit
http://www.beacosta.com/2006/01/how-do-i-sort-groups-of-data-items.html

Extending HeaderedItemsControl to have Footer !!!

The normal HeaderedContentControl in WPF gives us the facility to have a header up on the ItemsControl.This will be enough in most of the cases.But if you are looking for a ItemsControl which needs Footer too this is your solution.

1. Solution 1

Use the Tag Property to hold Content of Footer.And Template it to have Footer.No inheritance!!!

<HeaderedItemsControl>
<HeaderedItemsControl.Header>Header</HeaderedItemsControl.Header>
<TextBlock Text="Item1" Background="LightGray"/>
<TextBlock Text="Item2" Background="LightGray"/>
<TextBlock Text="Item3" Background="LightGray"/>
<HeaderedItemsControl.Tag>Header</HeaderedItemsControl.Tag>
<HeaderedItemsControl.Template>
<ControlTemplate TargetType="{x:Type HeaderedItemsControl}">
<Border Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height ="Auto"/>
<RowDefinition Height="*"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<ContentPresenter ContentSource="Header" Grid.Row="0"/>
<ItemsPresenter Grid.Row="1" />
<ContentPresenter ContentSource="Tag" Grid.Row="2"/>
</Grid>
</Border>
</ControlTemplate>
</HeaderedItemsControl.Template>
</HeaderedItemsControl>

Hierarchical databinding into TreeView

<Grid>
<Grid.Resources>
<XmlDataProvider x:Key="Company" XPath="*">
<x:XData>
<Reporting xmlns="">
<Person Name="CEO">
<Person Name="GM" >
<Person Name="PM-1" />
<Person Name="PM-2" >
<Person Name="PL" />
</Person >
<Person Name="PM-3" />
<Person Name="PM-4">
<Person Name="PL-2" />
<Person Name="PL-3" />
</Person>
<Person Name="PM-5" />
</Person>
</Person>
</Reporting>
</x:XData>
</XmlDataProvider>
<HierarchicalDataTemplate DataType="Person" ItemsSource ="{Binding XPath=*}">
<TextBlock Text="{Binding XPath=@Name}" />
</HierarchicalDataTemplate>

</Grid.Resources>
<TreeView ItemsSource="{Binding Source={StaticResource Company}, XPath=*}"/>
</Grid>

How to specify which property of my custom class should take the Content from xaml?

Use System.Windows.Markup.ContentProperty attribut on the class
Eg:
If you are creating a custom class for clock control and wanna Time to take the Content from xaml use as follows.

[System.Windows.Markup.ContentProperty("Time")]
public class Clock : Control {
public DateTime Time{
}
}

Hence the xaml looks like

<MyControl:Clock >
4:30:34
</MyControl:Clock >