DateTimePicker fromDatePicker = new DateTimePicker();
fromDatePicker.bindBidirectionalSelected(model.from);
from.setCenter(fromDatePicker.createContent());
DateTimePicker toDatePicker = new DateTimePicker();
toDatePicker.bindBidirectionalSelected(model.to);
to.setCenter(toDatePicker.createContent());
ArrayList<EmptySelectionWorkaround> states = new ArrayList<EmptySelectionWorkaround>();
for (WorkflowInstanceState state: WorkflowInstanceState.values()){
states.add(new EmptySelectionWorkaround(state,state.toString()));