Flutter : Autorun a function whenever a screen is opened - firebase

Question

I want to run a function to check Firestore data everytime a screen is loaded.
Here is my code :
class PlaceTile extends StatefulWidget {
//String flag='inactive';
final Place place;
PlaceTile({ this.place });
#override
_PlaceTileState createState() => _PlaceTileState(place);
}
class _PlaceTileState extends State<PlaceTile> {
final Place place;
_PlaceTileState(this.place);
String flag = 'inactive';
void getUserById(String id) {
DatabaseService().placesCollection.document(id).get().then((DocumentSnapshot doc) {
print(doc.data);
});
}
checkUserStatus() async {
final FirebaseAuth auth = FirebaseAuth.instance;
final FirebaseUser user = await auth.currentUser();
String uid = user.uid;
UserDatabaseService().userCollection.getDocuments().then((QuerySnapshot snapshot) {
snapshot.documents.forEach((DocumentSnapshot doc) {
if(doc.documentID == uid)
{
if(doc.data['status']=='true')
{
setState(() {
flag = 'active';
});
}
else
{
setState(() {
flag = 'inactive';
});
}
}
});
});
return flag;
}
void showQueueDetailsPanel() {
showModalBottomSheet(context: context, builder: (context) {
return Container(
padding: EdgeInsets.symmetric(vertical: 20.0, horizontal: 60.0),
child: QueueDetails(value: place.name),
);
});
}
String value;
#override
initState() {
super.initState();
checkUserStatus();
}
Widget build(BuildContext context) {
return Padding(
padding: EdgeInsets.only(top: 8.0),
child: Card(
margin: EdgeInsets.fromLTRB(20.0, 6.0, 20.0, 0.0),
child: ListTile(
isThreeLine: true,
leading: CircleAvatar(
radius: 25.0,
backgroundColor: Colors.white,
),
title: Text(place.name),
subtitle: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
//Text("People "+place.totalPeople.toString()),
Text(""),
Text("Token "+place.tokenAvailable.toString()),
],
),
trailing: FlatButton.icon(
icon: Icon(Icons.add_box_rounded),
label: Text('Join'),
onPressed: checkUserStatus() =='inactive' ? showQueueDetailsPanel : null,
),
),
)
);
}
}
The code in its current state doesn't perform the way I expect. It s a fallacy actually. Once flag is set to active, the Join buttons get disabled and for them to get re-enabled they need to be pressed for condition to be checked. But that's not possible since the buttons can't be pressed as they are disabled.
I want to run checkUserStatus() everytime this page with PlaceTile is loaded. How can I achieve that? A code snippet would be helpful.

Answer 1

Add your function to initState:
#override
void initState() {
super.initState();
checkUserStatus();
}

Answer 2

Widget build(BuildContext context) {
return FutureBuilder(
future: futurePackageListModel,
builder: (BuildContext context,
AsyncSnapshot<List<Model>> snapshot) {
if (snapshot.hasData) {
return YourWidget();
} else if (snapshot.hasError) {
return ApiStatusFail();
} else {
return Center(child: CircularProgressIndicator());
}
},
);
}