Why when i add data to firebase, the data keep looping? - flutter

Question

I'm new to flutter and firebase and I do not know why when I upload any data to firebase the data will keep repeating the same thing but when I hot restart the upload item back to 1, this is my code:
Future getDocId() async {
await FirebaseFirestore.instance
.collection('users')
.orderBy('mobile', descending: true)
.get()
.then(
(snapshot) => snapshot.docs.forEach(
(document) {
print(document.reference);
docIDs.add(document.reference.id);
},
),
);
}
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Expanded(
child: FutureBuilder(
future: getDocId(),
builder: (context, snapshot) {
return ListView.builder(
itemCount: docIDs.length,
itemBuilder: (context, index) {
return Padding(
padding: const EdgeInsets.all(10.0),
child: ListTile(
title: ReadUser(documentId: docIDs[index]),
tileColor: Colors.purple[100],
),
);
},
);
},
),
),
This is my future builder
return FutureBuilder<DocumentSnapshot>(
future: users.doc(documentId).get(),
builder: ((context, snapshot) {
if (snapshot.connectionState == ConnectionState.done) {
Map<String, dynamic> data =
snapshot.data!.data() as Map<String, dynamic>;
return Text('Name:' +
'${data['name']}' +
"\n"
'Email:' +
'${data['email']}' +
"\n"
'Mobile Number:' +
'+' +
'${data['mobile']}' +
"");
}
return Text('Loading..');
}),
);

Answer 1

the way you are fetching your data is wrong, instead of pass the result into outside variable you need to return it like this, I assume docIDs is a list of string:
Future<List<String>> getDocId() async {
try {
var snapshot = await FirebaseFirestore.instance
.collection('users')
.orderBy('mobile', descending: true)
.get();
return snapshot.docs.map((document) => document.reference.id).toList();
} catch (e) {
return [];
}
}
then change your FutureBuilder to this:
FutureBuilder<List<String>>(
future: getDocId(),
builder: (context, snapshot) {
switch (snapshot.connectionState) {
case ConnectionState.waiting:
return Text('Loading....');
default:
if (snapshot.hasError) {
return Text('Error: ${snapshot.error}');
} else {
List<String> data = snapshot.data ?? [];
return ListView.builder(
itemCount: data.length,
itemBuilder: (context, index) {
return Padding(
padding: const EdgeInsets.all(10.0),
child: ListTile(
title: ReadUser(documentId: data[index]),
tileColor: Colors.purple[100],
),
);
},
);
}
}
},
),