how to pass Future<int> to super class - flutter

Question

I am trying to learn Flutter and BLoC pattern. So, I created a simple counter app. Initially count value is 0 and it increases/decreases as respective buttons are pressed. The initial value(zero) is sent to the initial state as follows.
class CounterBloc extends Bloc<CounterEvent, CounterState> {
CounterBloc() : super(CounterInitialState(0));
The Counter app worked as expected, but whenever I restart the app count starts from zero. Now I wish to start the count from where I left. I read about SharedPreferences and could successfully save the current value. But I can't load the value and send it to CounterInitialState()(The argument type 'Future' can't be assigned to the parameter type 'int'). How can I achieve this?
My counter_bloc.dart looks like this;
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:bloc/bloc.dart';
import 'package:meta/meta.dart';
import 'package:sampleOne/config/config.dart';
import 'package:shared_preferences/shared_preferences.dart';
part 'counter_event.dart';
part 'counter_state.dart';
class CounterBloc extends Bloc<CounterEvent, CounterState> {
CounterBloc() : super(CounterInitialState(0));
#override
Stream<CounterState> mapEventToState(
CounterEvent event,
) async* {
if (event is CounterIncrementEvent) {
yield* _mapIncrementEvent(event.countVal);
}
if (event is CounterDecrementEvent) {
yield* _mapDecrementEvent(event.countVal);
}
}
}
Stream<CounterState> _mapIncrementEvent(val) async* {
await saveData(val);
yield CounterIncrementState(val + 1);
}
Stream<CounterState> _mapDecrementEvent(val) async* {
await saveData(val);
yield CounterDecrementState(val + 1);
}
Future<bool> saveData(int val) async {
SharedPreferences pref = await SharedPreferences.getInstance();
return pref.setInt('key', val + 1);
}
Future<int> loadData() async {
SharedPreferences pref = await SharedPreferences.getInstance();
return pref.getInt('key') ?? 0;
}
Please help.

Answer 1

you need to wrap your widget with a FutureBuilder widget.
for example
FutureBuilder<int>(
future: _bloc.loadData(),
initalData: 0,
builder: (context, snapshot) {
return Text(snapshot.data.toString());
}
)

Answer 2

Where do you call loadData()?
Maybe you need to to put an await before like this:
Future<int> data = loadData();
int data = await loadData();
Your function is asynchronous so it returns a Future, add await to get an integer