Interop WPF in WinForms, how to handle events from WPF control

Question

I'm working with some WPF Interoperability in a WinForms application. I have the following set up.

• WinForms UserControl WFControl
  • WPF UserControl GalleryControl
    • ListBox GalleryItems
      • ListBox ItemTemplate GalleryItem

Winforms hosting the GalleryControl, which has GalleryItems (ListBox) that has a ItemTemplate of GalleryItem.

Now in the WFControl I want to see when GalleryItems has it's SelectionChanged Event triggered.

My current attempts have tried to:

• Handle the SelectionChanged Event in GalleryControl and have it raise a seperate public event that my winforms can read, but I can't handle the event like that since it's not a routed event. This would work if I could figure out how to handle that. applicable code:

  public event ClaimGallery SelectedClaimChanged;
  public ViewModels.InsuranceClaimViewModel ClaimViewModel { get; set; }
  public int SelectedClaimID
  {
      get
      {
          return ((Models.InsuranceClaim) ClaimList.SelectedItem).ID;
      }
  }
  public ClaimGallery()
  {
      InitializeComponent();
      ClaimViewModel = new ViewModels.InsuranceClaimViewModel();
      DataContext = ClaimViewModel;
      ClaimList.ItemsSource = ClaimViewModel.InsuranceClaims;
      ClaimList.SelectionChanged += ClaimSelectionChanged;
  }
  
  private void ClaimSelectionChanged(object sender, EventArgs e)
  {
      //This is the part that doesn't work
      ClaimList.RaiseEvent(new RoutedEventArgs(SelectedClaimChanged, this));
  } 
  

I've also seen that I could potentially find the ListBox via some control tree browsing the subscribe to the actual event in the WFControl but I can't seem to figure how to do this in an interop'd control.

Answer 1

I have similar problems in my current project, and I'm solving it the way you describe. The WPF controls re-raises a public (normal) event, that is then handled by the WinForms control.

Honestly I don't get the part where you are stating that is has to be routed in order to be handled by Winforms.

my winforms can read, but I can't handle the event like that since it's not a routed event

you use "+=" to handle this one ...