Currently the ChoiceBox uses a SelectionModel to define the selected 'value'. Since the selectedItem is read-only this does not support bi-directional binding in a way that is easy for use in typical data entry screens (i.e. forms) or FXML.

A suggestion is to include a valueProperty in ChoiceBox directly that is synchronized with the selectedItem. This valueProperty would then allow for bi-directional binding and would update the selection model accordingly (e.g. by calling select(Item)).