Update progress bar in MainWindow from a different Thread

Question

I know this question has been asked several times an I spent all day trying to understand other answers, but since I am very new to C# and WPF nothing helped me so far. I wi

Answer 1

You can use Dispatcher.BeginInvoke() to push UI changes on the UI thread rather than worker thread. Most important thing - you need to access Dispatcher which is associated with UI thread not a worker thread you are creating manually. So I would suggest cache Dispatcher.Current and then use in a worker thread, you can do this via ParametersClass or just declaring a dispatchr field on a class level.

public partial class MainWindow
{
    private Dispatcher uiDispatcher;

    public MainWindow()
    {
        InitializeComponents();

        // cache and then use in worker thread method
        this.uiDispatcher = uiDispatcher;
    }

    public void MyLongCalculations(object myvalues)
    {
        ParameterObject values = (ParameterObject)myvalues;
        this.uiDispatcher.BeginInvoke(/*a calculations delegate*/);
    }
}

Also if you need to pass a UI dispatcher in some service/class (like ParametersClass) I would suggest take a look at this nice SO post which show how you can abstract it by an interfaces with ability to push UI changes synchronously/asynchronously so it would be up to a caller (basically use Invoke() or BeginInvoke() to queue a delegate in the UI messages pipeline).