Lets say i have an activity with InArgument<int> ProductId

I'd like to expose in the activity designer a combobox to show all Products and the user can select a product.

I can show the list of product in the combo no problem. But how do I bind the selected product to the InArgument<int> of my custom activity?

I suppose I need some kind of ValueConverter? Not sure how to code the value converter for this case, if anybody has an idea, suggestion, will be helpful. I have to convert the InArgument<int> to an int? and the convert back from int to InArgument<int>

Thanks,