How do I pass a WPF object that was created in thread X, to thread Y?

Question

I create a SolidColorBrush on some non-GUI thread, and want to pass it to a GUI thread to display it, but I get InvalidOperationException: The calling thread cannot access this object because a different thread owns it. (even if I try to Freeze(); it). How do I pass object that was created in thread X to thread Y ?

I know I can create this SolidColorBrush object in the GUI thread with Dispatcher, but that would complicate everything... I want to create it in the worker thread.

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Additional details:

I initialize some static delegate in some static class, to allow sending messages from business layer to GUI:

public static class Gui{
    private static PrintMethodDelegate _printMethod;
    public static void InitializeGuiInterface(PrintMethodDelegate printMethod){
        _printMethod = printMethod;
    }
    public static void Print(GuiMessage data) { _printMethod(data); }
}

Initialization (in the GUI thread):

Gui.InitializeGuiInterface(_messagesToUserHandler.PrintMessage);

Then in another (non-gui) thread, I use it:

Gui.Print(new GuiMessage(testDescription) { Foreground = new SolidColorBrush(someColor) });

while GuiMessage is:

public class GuiMessage {
    public string Msg { get; set; }

    private SolidColorBrush _foregroundBrush;
    public SolidColorBrush Foreground
    {
        get { return _foregroundBrush; }
        set { _foregroundBrush = value; }
    }
}

Answer 1

You can create wpf resources in another thread if you freeze them, after that the element can be passed to yet another thread or the gui thread. Remember that a once frozen object can only be modified by making a copy and using that copy. You can't freeze objects that have Bindings or animations attached to it.

Answer 2

You need to use a Delegate to safe invoke the control.

Use

Control.Invoke

or

Control.BeginInvoke

for this purpose.

private delegate void SetControlPropertyThreadSafeDelegate(Control control, string propertyName, object propertyValue);

public static void SetControlPropertyThreadSafe(Control control, string propertyName, object propertyValue)
{
  if (control.InvokeRequired)
  {
    control.Invoke(new SetControlPropertyThreadSafeDelegate(SetControlPropertyThreadSafe), new object[] { control, propertyName, propertyValue });
  }
  else
  {
    control.GetType().InvokeMember(propertyName, BindingFlags.SetProperty, null, control, new object[] { propertyValue });
  }
}

If you do not use the delegate to safe-invoke them, You will get the exception.

Check these links:

How to update the GUI from another thread in C#?enter link description here

enter link description here