Flutter problem with saving the value from document from database to a initState value - flutter

Question

I have a problem with fetching value from database document to a variable called in initState method. When I am doing that there is a problem with null value and I think that get() method from Firebase is taking the value too late(it happens when i reload the scene).
bool _dark;
bool options;
MainModel model;
final MyUser myUser;
final UserSettings userSettings;
_SettingsOnePageState(this.userSettings, this.myUser);
final user = FirebaseAuth.instance.currentUser;
#override
void initState() {
super.initState();
// _dark = false;
FirebaseFirestore.instance
.collection("settings")
.doc(user.uid)
.get()
.then((value) {
print(value.data()['darkMode']);
_dark = value.data()['darkMode'];
});
options = false;
}
Brightness _getBrightness() {
return _dark ? Brightness.dark : Brightness.light;
}
#override
Widget build(BuildContext context) {
return Theme(
// return StreamProvider<QuerySnapshot>.value(
isMaterialAppTheme: true,
data: ThemeData(
brightness: _getBrightness(),
),
// value: SettingsUser().settings,
child: StreamBuilder<UserSettings>(
//setting the stream for settings from database
stream: DatabaseUser(userId: user.uid).userData,
builder: (context, snapshot) {
if (snapshot.hasData) {
//data for user from database
UserSettings userSettings = snapshot.data;
// _dark = userSettings.darkMode;
// print("dark mode " + userSettings.darkMode.toString());
return Form(
key: _formKey,
child: Scaffold(
backgroundColor: _dark ? null : Colors.grey.shade200,
appBar: AppBar(
//elevation: 10,
brightness: _getBrightness(),
iconTheme: IconThemeData(
color: _dark ? Colors.white : Colors.black),
backgroundColor: Colors.transparent,
title: Text(
'Change theme',
style: TextStyle(
color: _dark ? Colors.white : Colors.black),
textAlign: TextAlign.center,
),
actions: <Widget>[
IconButton(
icon: Icon(Icons.auto_awesome),
onPressed: () {
setState(() {
_dark = !_dark;
});
},
)
],
),
body: Stack(fit: StackFit.expand, children: <Widget>[
SingleChildScrollView(
//padding: const EdgeInsets.all(16.0),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Stack(
children: <Widget>[
Align(
alignment: Alignment.center,
child: Text(
userSettings.nick,
textScaleFactor: 4,
style: TextStyle(
color: _dark
? Colors.white
: Colors.purple[500],
//fontWeight: FontWeight.w500,
),
)),
const SizedBox(height: 50.0),
],
),
Stack(
children: <Widget>[
Align(
alignment: Alignment.center,
child: Container(
// width: 200,
// height: 200,
child: CircleAvatar(
radius: 100.0,
backgroundImage:
//NetworkImage(user.photoURL),
NetworkImage(
userSettings.pictureUrl),
),
),
),
],
),
//const SizedBox(height: 20.0),
if (options == true) ...[
//SettingsEdit(),
//NickChange(),
ImageInput(),
],
const SizedBox(height: 10.0),
Card(
elevation: 4.0,
margin: const EdgeInsets.fromLTRB(
32.0, 8.0, 32.0, 16.0),
shape: RoundedRectangleBorder(
borderRadius:
BorderRadius.circular(10.0)),
child: Column(
children: <Widget>[
ListTile(
leading: Icon(
Icons.account_box,
color: Colors.purple,
),
title: Text("Change Nickname"),
trailing:
Icon(Icons.keyboard_arrow_right),
onTap: () {
//open change nick
//changeNick();
},
),
_buildDivider(),
ListTile(
leading: Icon(
Icons.add_a_photo,
color: Colors.purple,
),
title: Text("Change Photo"),
trailing:
Icon(Icons.keyboard_arrow_right),
onTap: () {
//open change photo
//changePhoto();
},
),
_buildDivider(),
ListTile(
leading: Icon(
Icons.lock_rounded,
color: Colors.purple,
),
title: Text("Change Password"),
trailing:
Icon(Icons.keyboard_arrow_right),
onTap: () {
//open change password
//changePassword();
},
),
_buildDivider(),
ListTile(
leading: Icon(
Icons.location_on,
color: Colors.purple,
),
title: Text("Change Your Location"),
trailing:
Icon(Icons.keyboard_arrow_right),
onTap: () {
//open change location
},
),
],
),
),
const SizedBox(height: 20.0),
]))
])));
}
return Scaffold();
}));
}
debug console
settings where I use theme now
Do you know how to avoid this null in initState? I am trying to change theme of the app and I am taking that from Firebase document whick I created when the user registered. Than I will be changing it in user settings and also want to use it(this theme) in whole app.
Thanks for help

Answer 1

InitState is not async (meaning execution doesn't wait for your firebase call to complete). This means that your view will be rendered before you assign _dark a value.
If you want to wait until that call is complete, use something called FutureBuilder.