Can't compile pane.GetParentToolWindow()

[KA]

Hello,

i am trying to resize a radPane to fit its content when it's state changed to floating. I read in this forum that i should get the parent window and set the size of the parent toolwindow manually, but i cannot compile it:

'TelerikRadPaneTest.CustomPane' does not contain a definition for 'GetParentToolWindow' and no extension method 'GetParentToolWindow' accepting a first argument of type 'TelerikRadPaneTest.CustomPane' could be found (are you missing a using directive or an assembly reference?)

According to the official API the method should be in the assembly i am using:
2012.3.1129.40 Telerik.Windows.Controls
2012.3.1129.40 Telerik.Windows.Controls.Data
2012.3.1129.40 Telerik.Controls.Docking
2012.3.1129.40 Telerik.Controls.Navigation


MainWindow.xaml

<Window x:Class="TelerikRadPaneTest.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
        xmlns:c="clr-namespace:TelerikRadPaneTest"
        Title="MainWindow" Height="350" Width="525">
    <DockPanel>
        <telerik:RadDocking PaneStateChange="RadDocking_PaneStateChange_1" telerik:AnimationManager.IsAnimationEnabled="False" HasDocumentHost="False" Margin="0,50,0,0" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2"  Grid.RowSpan="2" telerik:StyleManager.Theme="Windows8" BorderThickness="0">

            <telerik:RadSplitContainer telerik:ProportionalStackPanel.RelativeSize="120, 200" MinWidth="450" InitialPosition="DockedLeft" telerik:StyleManager.Theme="Windows8">
                <telerik:RadPaneGroup>
                    <c:CustomPane CanUserPin="False" CanUserClose="False">
                        <ScrollViewer>
                            <TextBlock Text="Very Long Scrollable Text"/>
                        </ScrollViewer>
                    </c:CustomPane>
                </telerik:RadPaneGroup>
            </telerik:RadSplitContainer>
        </telerik:RadDocking>
    </DockPanel>
</Window>

MainWindow.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Telerik.Windows.Controls;

namespace TelerikRadPaneTest
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void RadDocking_PaneStateChange_1(object sender, Telerik.Windows.RadRoutedEventArgs e)
        {
            var radDock = sender as RadDocking;
            if (radDock.IsLayoutChanging)
            {
                var pane = e.OriginalSource as CustomPane;
                if (pane != null)
                {
                    var scrollviewer = pane.Content as ScrollViewer;
                    var view = scrollviewer.Content as TextBlock;
                    Size size = new Size(view.ActualWidth, view.ActualHeight);
                    Point loc = radDock.PointToScreen(new Point(0, 0));

                    //start, this won't compile

                    var win = pane.GetParentToolWindow();
                    //win.Width = size.Width;
                    //win.Height = size.Height;

                    //end
                }
            }
        }
    }
}

CustomPane.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Telerik.Windows.Controls;

namespace TelerikRadPaneTest
{
    public class CustomPane : RadPane
    {
        public CustomPane()
            : base()
        {
            base.ContextMenuTemplate = null;
        }

        protected override void OnMouseEnter(System.Windows.Input.MouseEventArgs e)
        {
            this.ChangeVisualState(true);
        }


        protected override void OnMouseUp(System.Windows.Input.MouseButtonEventArgs e)
        {
            base.OnMouseUp(e);

            if (!this.IsPinned)
            {
                this.IsPinned = true;
            }
        }


    }

}

[KA]

ok i just figured it out.
should have read the api description carefully in the first place..

i was missing an explicit

using Telerik.Windows.Controls.Docking;

as this is an extension Method

no compile errors any more