Group an ItemsControlby a property of itemsource model

Question

With this class:

Public Class PageBetModel
Private _name As String

Public Property Name As String
    Get
        Return _name
    End Get
    Set(ByVal value As String)
        _name = value
    End Set
End Property

Private _group As String

Public Property Group As String
    Get
        Return _group
    End Get
    Set(ByVal value As String)
        _group = value
    End Set
End Property
End Class

I want to create an style with an ItemsControl, painting the Name Property, and grouping by Group property.

<ItemsControl ItemsSource="{Binding Path=Model}" ItemsPanel="{DynamicResource MyPanel}" ItemTemplate="{DynamicResource MyTemplate}"/>

<DataTemplate x:Key="MyTemplate">
    <Border MinHeight="100" BorderThickness="0,0,0,2" BorderBrush="#dfe1e0">

            <TextBlock x:Name="RadioButtonText" Margin="16,40,16,16" Width="287" Text="{Binding Path=Name}" FontFamily="Arial" FontSize="17" Foreground="#474747" FontWeight="SemiBold" TextWrapping="Wrap" VerticalAlignment="Top" HorizontalAlignment="Left"/>

    </Border>
</DataTemplate>

I want to display this simple design but grouping the different names with an Expander by the Group Property.

Answer 1

Set the ItemsSource to a grouped CollectionViewSource:

<CollectionViewSource x:Key="cvs" Source="{Binding Path=Model}">
    <CollectionViewSource.GroupDescriptions>
        <PropertyGroupDescription PropertyName="Group" />
    </CollectionViewSource.GroupDescriptions>
</CollectionViewSource>

...and define a GroupStyle that contains an Expander:

<ItemsControl ItemsPanel="{DynamicResource MyPanel}"
            ItemsSource="{Binding Source={StaticResource cvs}}"
            ItemTemplate="{DynamicResource MyTemplate}">
    <ItemsControl.GroupStyle>
        <GroupStyle>
            <GroupStyle.ContainerStyle>
                <Style TargetType="{x:Type GroupItem}">
                    <Setter Property="Template">
                        <Setter.Value>
                            <ControlTemplate>
                                <Expander IsExpanded="True">
                                    <Expander.Header>
                                        <TextBlock Text="{Binding Name}" FontWeight="Bold" Foreground="Gray" FontSize="22" VerticalAlignment="Bottom" />
                                    </Expander.Header>
                                    <ItemsPresenter />
                                </Expander>
                            </ControlTemplate>
                        </Setter.Value>
                    </Setter>
                </Style>
            </GroupStyle.ContainerStyle>
        </GroupStyle>
    </ItemsControl.GroupStyle>
</ItemsControl>