prs/prs.desktop/Panels/Suppliers/SupplierPanel.xaml

<UserControl x:Class="PRSDesktop.SupplierPanel"
             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:dynamicGrid="clr-namespace:InABox.DynamicGrid;assembly=InABox.Wpf"
             mc:Ignorable="d"
             d:DesignHeight="450" d:DesignWidth="800">
    <dynamicGrid:DynamicSplitPanel x:Name="SplitPanel" View="Combined" AnchorWidth="500" Anchor="Detail" MasterCaption="Supplier List"
                                   DetailCaption="Supplier Details" OnChanged="SplitPanel_OnChanged">

        <dynamicGrid:DynamicSplitPanel.Header>
            <Border BorderBrush="Gray" BorderThickness="0.75" Background="WhiteSmoke" Height="25">
                <Label Content="Supplier List" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" />
            </Border>
        </dynamicGrid:DynamicSplitPanel.Header>

        <dynamicGrid:DynamicSplitPanel.Master>
            <local:SupplierGrid Grid.Column="0" Grid.Row="1" Grid.RowSpan="2" x:Name="Suppliers" OnSelectItem="Suppliers_OnSelectItem"/>
        </dynamicGrid:DynamicSplitPanel.Master>

        <dynamicGrid:DynamicSplitPanel.Detail>

            <dynamicGrid:DynamicTabControl x:Name="SupplierDetails" SelectionChanged="SupplierDetails_SelectionChanged"
                                           BorderThickness="0" Background="WhiteSmoke" Margin="0,-2,0,-2">
                
                <dynamicGrid:DynamicTabItem x:Name="Contacts" Header="Contacts">
                    <local:SupplierContactGrid x:Name="SupplierContacts" />
                </dynamicGrid:DynamicTabItem>
                
                <dynamicGrid:DynamicTabItem x:Name="Products" Header="Products">
                    <local:SupplierProductGrid x:Name="SupplierProducts" />
                </dynamicGrid:DynamicTabItem>
                
                <dynamicGrid:DynamicTabItem x:Name="Spreadsheets" Header="Spreadsheets">
                    <local:SupplierSpreadsheetGrid x:Name="SupplierSpreadsheets" />
                </dynamicGrid:DynamicTabItem>
                
            </dynamicGrid:DynamicTabControl>

        </dynamicGrid:DynamicSplitPanel.Detail>

    </dynamicGrid:DynamicSplitPanel>

</UserControl>