MultipleChoiceInput with variables choices

[davidebazzi]

I have the requirement to filter out some of the initial possible choices.
This is not yet possible neither with the values from the resources neither with the directValues these values are used during BuildShowProperty and can't be changed during the action use.
To avoid having to implement from scratch an input similar to MultipleChoiceInput, I suggest to allow to instantiate a derived MultipleChoiceProperty in a derived MultipleChoiceInput.
Then in the derived MultipleChoiceProperty it is easy to change the possible choices through the Choices property

[davidebazzi]

@SOFAgh what do you think?

[SOFAgh]

I didn't check deeply, but in the code it looks like when you change the Choices property of the MultipleChoiceProperty, next time when you open the dropdown list, there are the modified choices available. MultipleChoiceInput has the IInputObject.GetShowProperty() method, which returns a MultipleChoiceProperty, where you could change the Choices.
But I see: the interface IInputObject is private. Maybe we should make it public?
Or should we add a method to MultipleChoiceInput like SetChoices? Here we could access multipleChoiceProperty.Choices