I want to save user preferences using Flutter's SharedPreference. But the registered preferences are ALL null at new start (when app have been closed, not unistalled).
settings.dart :
import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';
class SettingsPage extends StatefulWidget{
@override
_SettingsPageState createState() => new _SettingsPageState();
}
class _SettingsPageState extends State<SettingsPage>{
bool _param1IsON;
bool _param2IsON;
bool _param3IsON;
@override
void initState() {
super.initState();
_param1IsON = false;
_param2IsON = false;
_param3IsON = false;
loadPreferences();
}
Future<Null> loadPreferences() async {
SharedPreferences _preferences = await SharedPreferences.getInstance();
if(_preferences.getBool('setted') == null || !_preferences.getBool('setted'))
SharedPreferences.setMockInitialValues({}); // Library fix line
bool param1IsON = _preferences.getBool('param1IsON');
bool param2IsON = _preferences.getBool('param2IsON');
bool param3IsON = _preferences.getBool('param3IsON');
setState(() {
_param1IsON = (param1IsON != null)? param1IsON : _param1IsON;
_param2IsON = (param2IsON != null)? param2IsON : _param2IsON;
_param3IsON = (param3IsON != null)? param3IsON : _param3IsON;
});
_preferences.setBool('setted', true);
}
Future<Null> setBoolSettings(String key, bool value) async {
switch(key){
case 'param1IsON':
setState(() {
_param1IsON = value;
});
break;
case 'param2IsON':
setState(() {
_param2IsON = value;
});
break;
case 'param3IsON':
setState(() {
_param3IsON = value;
});
break;
default:
print("Unknown settings '$key'");
}
SharedPreferences _preferences = await SharedPreferences.getInstance();
await _preferences.setBool(key, value);
}
@override
Widget build(BuildContext context) {
return new ListView(
children: <Widget>[
new ListTile(
title: new Text(Param 1'),
trailing: new Switch(value: _param1IsON,
onChanged: (bool newValue) {
setBoolSettings('param1IsON', newValue);
}),
),
new ListTile(
title: new Text('Param 2'),
trailing: new Switch(value: _param2IsON,
onChanged: (bool newValue) {
setBoolSettings('param2IsON', newValue);
}),
),
new ListTile(
title: new Text('Param 3'),
trailing: new Switch(value: _param3IsON,
onChanged:
(bool newValue) {
setBoolSettings('param3IsON', newValue);
}),
),
]
);
}
}
What I get:
At lunch 3 parameters are false. If I turn 'ON' one of them, wait 2s (it is not an async problem), then close the app and Start again... All of my parameters are false.
What I want:
At lunch 3 parameters are false. I turn 'ON' one of them. I close the app. Start again. The previous param I turned 'ON' is still true.
