<DockPanel
   Name="ContainerDockPanel"
   xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
   xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
   xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:UserControls="clr-namespace:UserControls" mc:Ignorable="d" MaxWidth="500" Height="300" MinHeight="110">

	<DockPanel.RenderTransform>
		<TranslateTransform X="0" Y="0"/>
	</DockPanel.RenderTransform>
	
	<StackPanel Name="WindowList">
		<Button Name="ShowUserControl">Show UserControl</Button>
	</StackPanel>
</DockPanel>

<UserControl Name="TestWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
   xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
   xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
	<StackPanel>
		<Button>User Control!</Button>
	</StackPanel>
</UserControl>

public class TestController : MonoBehaviour
{
	private NoesisGUIPanel _uiPanel;
	private FrameworkElement _Root;
	private Button _ShowInvButton;
	private StackPanel _WindowList;
	private DockPanel _DockPanel;
	// Use this for initialization
	private void Start()
	{
		_uiPanel = NoesisGUISystem.GetPanel("TestController");

		_Root = _uiPanel.GetRoot<FrameworkElement>();
		_DockPanel = _Root.FindName<DockPanel>("ContainerDockPanel");
		_ShowInvButton = _Root.FindName<Button>("ShowUserControl");
		Debug.Log(_ShowInvButton.GetName());
		_ShowInvButton.Click += ShowInvButtonOnClick;
		_WindowList = _DockPanel.FindName<StackPanel>("WindowList");
		Debug.Log(_WindowList.GetName());
	}

	private void ShowInvButtonOnClick(BaseComponent arg0, RoutedEventArgs routedEventArgs)
	{
		ShowInventory();
	}

	private void ShowInventory()
	{
		_WindowList.GetChildren().Add(new TestWindow());
	}
}

namespace UserControls
{
	public class TestWindow : UserControl
	{
		private HandleRef swigCPtr;

		public static void Register()
		{
			// Override the source to indicate the user control xaml
			UserControl.SourceProperty.OverrideMetadata(typeof(TestWindow),
											new PropertyMetadata("Assets/_Game/NoesisUI/TestWindow.xaml"));
		}


		public TestWindow(IntPtr cPtr, bool cMemoryOwn)
			: base(cPtr, cMemoryOwn)
		{
			swigCPtr = new HandleRef(this, cPtr);
		}

		public TestWindow()
			: this(Noesis.Extend.New(typeof(TestWindow)), true)
		{
			Noesis.Extend.Register(typeof(TestWindow), swigCPtr.Handle, this);
		}

		public override void Dispose()
		{
			lock (this)
			{
				if (swigCPtr.Handle != IntPtr.Zero)
				{
					if (swigCMemOwn)
					{
						swigCMemOwn = false;
						if (Kernel.IsInitialized())
						{
							Noesis.Extend.Delete(typeof(TestWindow), swigCPtr.Handle);
						}
					}
					swigCPtr = new HandleRef(null, IntPtr.Zero);
				}
				GC.SuppressFinalize(this);
				base.Dispose();
			}
		}
	}
}

    <UserControl Name="TestWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
       xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
       xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
       x:Class="UserControls.TestWindow">
       <StackPanel>
          <Button>User Control!</Button>
       </StackPanel>
    </UserControl>