Flutter pass User instance to another state and keep it updated - dart

Question

I am trying to make a login/registration process and redirect user to a Dashboard view.
So I have this method:
Future _redirectToDashboard() async {
var route = new MaterialPageRoute(
builder: (BuildContext context) => new Dashboard(userID: userID),
);
Navigator.of(context).push(route);
}
And then call it after login() is finished.
_register().whenComplete(() => _redirectToDashboard());
And then in Dashboard I do this:
class Dashboard extends StatefulWidget
{
int userID;
Dashboard({Key key, this.userID}) : super(key: key);
#override
_Dashboard createState() => _DashboardState();
}
And use it with:
Text('User ID: ${widget.userID}')
But then I cannot do this in Dashboard class:
Dashboard({Key key, this.userID, this.name, this.balance}) : super(key: key);
even though I set it in a function above as:
builder: (BuildContext context) => new Dashboard(userID: userID, name: name, balance: balance),
But it doesn't work. I get an error that name for example is not defined Why can I only pass one parameter? And is there a way how can I update the Dashboard with new data every time user opens this state?
I read that I should create a seperate User class with all properties. But how can I apply it to a dashboard?

Answer 1

I assume you only added constructor parameters, without adding the actual class members.
class Dashboard extends StatefulWidget
{
final int userID;
final String name;
final String balance;
Dashboard({Key key, this.userID, this.name, this.balance}) : super(key: key);
#override
_Dashboard createState() => _DashboardState();
}