change method
Function used to change state.
This function receives the new value of state and preforms changes to the currentValue and the previousValue.
Implementation
@override
void change(T newValue, {StateChange<T>? stateChange}) {
componentState.change(newValue, stateChange: stateChange);
_stateController.add(
stateChange ?? StateChange(triggerEvent: null, newValue: newValue));
}