WPF - Canvas won't update when BackgroundWorker is completed - wpf

Question

I need to update my Canvas when BackgroundWorker is completed. When i update the Canvas through a button actionlistener it works perfect. But when i call my update function when backroundWorker is completed. The gui won't update.
The function that add items to the canvas:
public void AddItemsToCanvas()
{
int factor = 0;
cvList.Children.Clear();
foreach (ItemControl item in ItemControl.ItemsList)
{
cvList.Children.Add(item.updateName);
Canvas.SetLeft(item.updateName, 13);
Canvas.SetTop(item.updateName, factor + 10);
Canvas.SetZIndex(item.updateName, 1);
cvList.Children.Add(item.imageButton);
Canvas.SetLeft(item.imageButton, 180);
Canvas.SetTop(item.imageButton, factor + 13);
Canvas.SetZIndex(item.imageButton, 5);}}
The button that calls the update function:
private void Button_Click_1(object sender, RoutedEventArgs e)
{
updateCanvas();
}
public void updateCanvas()
{
Service serv = new Service();
serv.SuperlinkCompartments();
//Check for updates and add them to a List of updates
Update up = new Update();
up.PropertyChanged += new PropertyChangedEventHandler(Items_PropertyChanged);
up.ShowUpdates();
}
public void Items_PropertyChanged(object sender, PropertyChangedEventArgs e)
{
AddItemsToCanvas();
}
The Canvas updates perfectly when called from the button actionListener. But not working when the UpdateCanvas() is called from the BackgroundWorker event.
public void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
var item = dic3[(BackgroundWorker)sender];
int index = (int)item.controlButton.Tag;
item.Progressbar.Value = 0;
SystemInfo.SystemList[Update.UpdateList[index].SystemIndex].Version = Update.UpdateList[index].UpdateVersion;
lvSystems.ItemsSource = SystemInfo.SystemList;
updateCanvas();
}
I'm i missing something in the BackgroundWorker event function?

Answer 1

try using the `Dispatcher':
Application.Current.Dispatcher.Invoke(new Action(()=>
{
updateCanvas();
}), DispatcherPriority.Render);
then, inside your updateCanvas() method, add the following at the end:
cvList.UpdateLayout();