how to return more complex data than bool from popup v2

[maslewandowski]

i've read this https://github.com/CommunityToolkit/Maui/wiki/Migrating-to-Popup-v2 and this https://learn.microsoft.com/en-us/dotnet/communitytoolkit/maui/views/popup/popup-result

in my project i had this working with version 1 of popup (forgive me the use of dialog instead of popup)

var dialogResult = await popupService.ShowPopupAsync<CampaignsDialogViewModel>(onPresenting: vm => vm.SelectedCampaigns = SelectedCampaigns.ToObservableCollection());
if (dialogResult == default) return;
if (dialogResult is ObservableCollection<Campaign> campaigns)
{
//do something
}

now i migrated to this point:

var queryAttributes = new Dictionary<string, object>
{
    [nameof(CampaignsDialogViewModel.SelectedCampaigns)] = SelectedCampaigns.ToObservableCollection()
};

var result = await popupService.ShowPopupAsync<CampaignsDialogViewModel>(
    Shell.Current,
    options: PopupOptions.Empty,
    shellParameters: queryAttributes);

but i don't see a property to use in the result:

so i took a look at this:
https://learn.microsoft.com/en-us/dotnet/communitytoolkit/maui/views/popup/popup-result#awaiting-the-result-from-a-popup

and i understood it like this:

IPopupResult<ObservableCollection<Campaign>> dialogResult = await popupService.ShowPopupAsync<CampaignsDialogViewModel>(
    Shell.Current,
    options: PopupOptions.Empty,
    shellParameters: queryAttributes);

sadly this does not work.
can you help me please by giving me a simple best practice approach how to return more complex data than a bool?

i saw that i maybe need to update my code behind file of the popup by
public partial class CampaignsDialog : Popup<ObservableCollection<Campaign>>

but what to do then in my xaml?
x:TypeArguments="?"

[maslewandowski]

thanks claude sonnet 4.5.
the solution:

var popupResult = await popupService.ShowPopupAsync<CampaignsDialogViewModel, ObservableCollection<Campaign>>(
 Shell.Current,
options: PopupOptions.Empty,
shellParameters: queryAttributes);

so you have to use the generic overload: ShowPopupAsync<T, TResult> instead of just ShowPopupAsync<T>