updateNewStateX method
Update the 'new' StateX object from the 'old' StateX object. Returning to this app from another app will re-create the State object You 'update' the current State object using this function.
Implementation
@override
@protected
@mustCallSuper
void updateNewStateX(covariant StateX oldState) {
/// No 'setState()' functions are allowed
_setStateAllowed = false;
for (final con in controllerList) {
con.updateNewStateX(oldState);
}
/// Re-enable setState() function
_setStateAllowed = true;
}