How to: Enable horizontal and vertical item sizing within DockLayoutControl

The following code shows how to enable horizontal and vertical item sizing within a DockLayoutControl via the DockLayoutControl.AllowHorizontalSizing and DockLayoutControl.AllowVerticalSizing attached properties. Vertical sizing is enabled for GroupBox 1. Horizontal sizing is enabled for GroupBox 2 and GroupBox 3.

DockLayoutControl_Horz_Vert_Sizing

<Window x:Class="DockLayoutControl_Horz_Vert_Sizing.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:lc="http://schemas.devexpress.com/winfx/2008/xaml/layoutcontrol"
        Title="MainWindow" Height="350" Width="525">

    <Grid x:Name="LayoutRoot" Background="White">
        <lc:DockLayoutControl>
            <lc:GroupBox lc:DockLayoutControl.Dock="Top" Height="70" Header="GroupBox 1"
                lc:DockLayoutControl.AllowVerticalSizing="True"/>
            <lc:GroupBox lc:DockLayoutControl.Dock="Right" Header="GroupBox 2" 
                lc:DockLayoutControl.AllowHorizontalSizing="True"/>
            <lc:GroupBox lc:DockLayoutControl.Dock="Left" Header="GroupBox 3"
                lc:DockLayoutControl.AllowHorizontalSizing="True"/>
            <lc:GroupBox lc:DockLayoutControl.Dock="Client" Header="GroupBox 4"/>
        </lc:DockLayoutControl>
    </Grid>
</Window>