How do I set the already selected items of a CheckComboBox in the VM?

[HuygheDaphne-Marie]

Hi I'm having some trouble understanding how to properly set the selected items in a CheckComboBox (or get them) without breaking MVVM.

I've been able to get them by using a SelectionChanged event as a workaround. But multiple times I've encountered what seems to be view code being suggested as the fix to a databinding issue such as here

I'm wondering if I'm missing something obvious or if I don't understand a part of how HandyControl is meant to be used without violating the separation between VM & View in these cases. Since if I would somehow pass the items I want to have already be selected to the View and then set them, I would violate this.

(Not that it matters since it's not like you can wait until a DataContext is bound inside of a view and then do something as far as I know)

Could anyone point me the right way or explain?