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How to access separate WPF interface stream elements from the Manager thread?

I need to create a print preview (long) using wpf user interface elements like FixedDocument, FlowDocument, PageContent, BlockUIContainer and all that. To maintain the responsiveness of my user interface, I am doing this part in a separate thread of the Thread thread (BackgroundWorker will not work, since I need an STA thread). Everything is fine up to this point.
But after the print preview is displayed, I need to print and click the "Print" icon in the generated preview, throws the infamous "The calling thread cannot access this object because it has a different thread." an exception. So is there a way?

EDIT (CODE):

Dispatcher.CurrentDispatcher.Invoke(new Action(() =>  
    {  
        Thread thread = new Thread(() =>  
            {  
                FixedDocument document = renderFlowDocumentTemplate(report);  
                PrintPreview preview = new PrintPreview();  
                preview.WindowState = WindowState.Normal;  
                preview.documentViewer.Document = document;  
                preview.ShowDialog();  
            });  
        thread.SetApartmentState(ApartmentState.STA);  
        thread.Start();  
    }));`

, RenderFlowDocumentTemplate() ( ) . PrintPreview - , DocumentViewer, , "", "", "PrintDialog".

EDIT (XAML):

<cw:CustomWindow x:Class="MyApp.Reports.PrintPreview"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:cw="clr-namespace:MyApp.UI.CustomWindows;assembly=MyApp.UI.CustomWindows">    
    <DocumentViewer Margin="0,30,0,0" Name="documentViewer"></DocumentViewer>
</cw:CustomWindow>`
+5
6

- DocumentViewer . . .
, , Dispatcher, . "VerifyAccess" , .:)

+1

:

Action a = () =>
{
    //Code from another thread.
};
Dispatcher.BeginInvoke(a);
+1

- , , printpreview mainthread.

+1

""...

. , FrameworkElement ContentPresenter. , ItemsControl ContentPresenter FrameworkElement ObservableCollection<FrameworkElement> .

+1

, , , , , .

/// <summary>
/// Creates UI element on a seperate thread and transfers it to
/// main UI thread. 
/// 
/// Usage; if you have complex UI operation that takes a lot of time, such as XPS object creation.
/// </summary>
/// <param name="constructObject">Function that creates the necessary UIElement - will be executed on new thread</param>
/// <param name="constructionCompleted">Callback to the function that receives the constructed object.</param>
public void CreateElementOnSeperateThread(Func<UIElement> constructObject, Action<UIElement> constructionCompleted)
{
    VerifyAccess();

    // save dispatchers for future usage.
    // we create new element on a seperate STA thread
    // and then basically swap UIELEMENT Dispatcher.
    Dispatcher threadDispatcher = null;
    var currentDispatcher = Dispatcher.CurrentDispatcher;

    var ev = new AutoResetEvent(false);
    var thread = new Thread(() =>
        {
            threadDispatcher = Dispatcher.CurrentDispatcher;
            ev.Set();

            Dispatcher.Run();
        });

    thread.SetApartmentState(ApartmentState.STA);
    thread.IsBackground = true;
    thread.Start();

    ev.WaitOne();

    threadDispatcher.BeginInvoke(new Action(() =>
        {
            var constructedObject = constructObject();
            currentDispatcher.BeginInvoke(new Action(() =>
                {
                    var fieldinfo = typeof (DispatcherObject).GetField("_dispatcher",
                                                                       BindingFlags.NonPublic |
                                                                       BindingFlags.Instance);
                    if (fieldinfo != null)
                        fieldinfo.SetValue(constructedObject, currentDispatcher);

                    constructionCompleted(constructedObject);
                    threadDispatcher.BeginInvokeShutdown(DispatcherPriority.Normal);
                }), DispatcherPriority.Normal);
        }), DispatcherPriority.Normal);
}

:

 CreateElementOnSeperateThread(() =>
        {
            // running on new temp dispatcher.
            var loadsOfItems = new List<int>();
            for(var i = 0; i < 100000; i++)
                loadsOfItems.Add(i+12);


            var dataGrid = new DataGrid {ItemsSource = loadsOfItems, Width = 500, Height = 500};

            dataGrid.Measure(new Size(500, 500));
            dataGrid.Arrange(new Rect(0, 0, 500, 500));

            return dataGrid;
        }, result => SampleGrid.Children.Add(result));
+1

. Dispatcher beginInvoke-. , . , ,

  App.Current.Dispatcher.BeginInvoke(DispatcherPriority.Background, new Action(() =>
{
//you code goes here.
 }));

The begin invoke call processes your asynchronous call.

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