prs/prs.desktop/Components/ProductGroupSelector/ProductGroupSelector.xaml

<UserControl x:Class="PRSDesktop.ProductGroupSelector"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
             xmlns:local="clr-namespace:PRSDesktop"
             xmlns:Syncfusion="http://schemas.syncfusion.com/wpf"
             mc:Ignorable="d"
             d:DesignHeight="600" d:DesignWidth="200">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition Height="*" />
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto" />
            <ColumnDefinition Width="*" />
        </Grid.ColumnDefinitions>
        
        <Button x:Name="SelectAll" Grid.Row="0" Grid.Column="0" Content="None" Width="40" Height="25" Click="SelectAll_OnClick" BorderBrush="DimGray" BorderThickness="0.75"/>

        <Border Grid.Row="0" Grid.Column="1" Margin="2,0,0,0" BorderBrush="DimGray" BorderThickness="0.75" Background="WhiteSmoke">
            <Label Content="Product Groups" HorizontalContentAlignment="Center" Padding="0" VerticalContentAlignment="Center" />
        </Border>
        
        <Syncfusion:CheckListBox 
            x:Name="SelectedGroups"
            Grid.Row="1"
            Grid.ColumnSpan="2"
            Margin="0,2,0,0"
            DisplayMemberPath="Value"
            IsSelectAllEnabled="False" 
            IsCheckOnFirstClick="True"
            ItemChecked="SelectedGroups_OnItemChecked" />
            
    </Grid>

</UserControl>