Flutter API Fetch and Sending Data from One screen to another screen - flutter

Question

When I am logged in through the API I am getting the value User_id which I am able to print on console, but I want to use it on another screen.
So how can I send the data to another screen?
// First Screen
Future postMethod() async {
var api = Uri.parse("https://demo.likemyfiles.com/DS/api/auth/otp");
Map mapeddate = {
'phone': _phone.text,
'otp': _otp.text,
};
final response = await http.post(api, body: mapeddate);
print(response.body);
var res = json.decode(response.body);
print(res['user_id']);
Navigator.pushNamed(context, StartActivity.id); //here i want to send the User_Id
}
//Second Screen (Start Activity) in this screen there is a function FetchData where i want to use the data
Future fetchdata() async {
var url = await http.get(Uri.parse(
"http://demo.likemyfiles.com/DS/api/api_supervisor/supervisor/3")); //Instead of 3 i want
to use the User_Id variable
}

Answer 1

You should try to declare constructor the first page accept the id and push this id to second page or screen like this below code is first page
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => ABC.withId(
id,
),
),
)
the create constructor inside second page screen
class ABC extends StatefulWidget {
#override
_ABCState createState() => _ABCState();
var id;
ABC.withId(String uid) {
id = uid;
}
}
accept your id inside widget using widget.id