The calling thread cannot access this object because a different thread owns it.WPF

Question

Whenever I refresh a label, I got this error: The calling thread cannot access this object because a different thread owns it. I tried to invoke b

Answer 1

I started one non-UI Thread and within this thread I stared one UI thread too. So my requirement is like running an UI thread within a non-UI thread. When handling this scenario I got the following exception. "Exception: The calling thread cannot access this object because a different thread owns it."

In this case I used the Dispatcher.Invoke method of the UI element as follows and it worked well.

if (m_contextWindow == null)
{   
    System.Threading.Thread newWindowThread = new System.Threading.Thread(new ThreadStart( () =>
    {
        // Create and show the Window
        m_contextWindow = new ContextWindow();
        m_contextWindow.DataContext = this;                            
        m_contextWindow.Show();
        // Start the Dispatcher Processing
        System.Windows.Threading.Dispatcher.Run();
    }));

    // Set the apartment state
    newWindowThread.SetApartmentState(ApartmentState.STA);
    // Make the thread a background thread
    newWindowThread.IsBackground = true;
    // Start the thread
    newWindowThread.Start();
}
else
{                     
    this.m_contextWindow.Dispatcher.Invoke(new ThreadStart(() => 
    {
        m_contextWindow.DataContext = this;
        if (m_contextWindow.Visibility == System.Windows.Visibility.Collapsed
         || m_contextWindow.Visibility == System.Windows.Visibility.Hidden)
            m_contextWindow.Visibility = System.Windows.Visibility.Visible;
    }));                            
}