Retrive a data from firebase database with Timer - database

Question

How can I retrieve a data from firebase database with Timer function in flutter app?
P.S.After user request data will be retrieved from firebase database 5 minutes later.
Thank you

Answer 1

So what you are do by calling where('index' isEqualTo: ' 0' is it first finds any documents with a field named index like above then it only returns the ones the has a value this is equal to to the one you provided

Answer 2

My code is just like below but it did not work with your code.#wcyankees424
body: StreamBuilder(
stream: qs.collection('collection').snapshots(),
builder: (context, snapshot) {
if (!snapshot.hasData) {
const Text('Loading');
return Center(
child: CircularProgressIndicator(),
);
} else {
return ListView.builder(
itemCount: snapshot.data.documents.length,
itemBuilder: (context, index) {
List<DocumentSnapshot> listedQS = snapshot.data.documents;
var random = new Random();
for (var i = listedQS.length - 1; i > 0; i--) {
var n = random.nextInt(i + 1);
var temp = listedQS[i];
listedQS[i] = listedQS[n];
listedQS[n] = temp;
}
DocumentSnapshot mypost = listedQS[0];

Answer 3

Future.delayed(Duration(minutes: 5), () {
Timer.periodic(Duration(minutes: 5), (Timer t) {
setState(() {});
});
});
okay put this in the stateful widget with you StreamBuilder this worked on my emulator. Let me know if it works for you.

Answer 4

Future<void> addEntry(Brew newBrew) async {
//value you want saved are stored in newBrew and passed in
Map<String, Object> entryData = {
'name': newBrew.name,
'strength': newBrew.strength,
'sugars': newBrew.sugars,
'index': newBrew.index,
};
await Firestore.instance.collection('//collection name').add(entryData);
}
Future<Brew> getEntries(Brew newBrew) async {
QuerySnapshot snapshot = await Firestore.instance
.collection('//Collection name')
.where('index', isGreaterThanOrEqualTo: Random().nextInt('//this number should be higher than the number of documents'))
.orderBy('index')
.limit(1)
.getDocuments();
if (snapshot.documents.isNotEmpty) {
Map<String, dynamic> documentData = snapshot.documents[0].data;
return Brew(
strength: documentData['strngth'],
sugars: documentData['sugars'],
name: documentData['name'],
index: documentData['index'],
);
} else {
snapshot = await Firestore.instance
.collection('//Collection name')
.where('index', isGreaterThanOrEqualTo: 0)
.orderBy('index')
.limit(1)
.getDocuments();
Map<String, dynamic> documentData = snapshot.documents[0].data;
return Brew(
strength: documentData['strngth'],
sugars: documentData['sugars'],
name: documentData['name'],
index: documentData['index'],
);
}
}
class Brew {
final String name;
final String sugars;
final int strength;
final int index;
Brew({
this.name,
this.sugars,
this.strength,
this.index,
});
}
you would create and field for every called index which would start at 0 increment by 1 for every entry in your in your database. This might help you

Answer 5

My code is like below how could I show text and image values with Querysnapshot method ? That you've mentioned with brew code! I cant use your code with below code structure...
Your code: #wcyankees424
snapshot = await Firestore.instance
.collection('//Collection name')
.where('index', isGreaterThanOrEqualTo: 0)
.orderBy('index')
.limit(1)
.getDocuments();
my code:
body: StreamBuilder(
stream: qs.collection('collection').limit(1).snapshots(),
builder: (context, snapshot) {
if (!snapshot.hasData) {
const Text('Loading');
} else {
return ListView.builder(
itemCount: snapshot.data.documents.length,
itemBuilder: (context, index) {
List<DocumentSnapshot> listedQS =
snapshot.data.documents; //listed documents
var random = new Random(); //dart math
for (var i = listedQS.length - 1; i > 0; i--) {
var n = random.nextInt(i + 1);
var temp = listedQS[i];
listedQS[i] = listedQS[n];
listedQS[n] = temp;
}
DocumentSnapshot mypost = listedQS[0];
return Stack(
children: <Widget>[
Container(
width: MediaQuery.of(context).size.width,
height: 350,
child: Padding(
padding: EdgeInsets.only(top: 8.0, bottom: 8.0),
child: Material(
color: Colors.white,
elevation: 14.0,
shadowColor: Color(0x882196F3),
child: Center(
child: Padding(
padding: EdgeInsets.all(8.0),
child: Column(
children: <Widget>[
Container(
width:
MediaQuery.of(context).size.width,
height: 200,
child: Image.network(
'${mypost['image']}',
fit: BoxFit.fill),
),
SizedBox(height: 10.0),
Text(
'${mypost['title']}',
style: TextStyle(
fontSize: 20.0,
fontWeight: FontWeight.bold),
),
SizedBox(height: 10.0),
Text(
'${mypost['subtitle']}',
style: TextStyle(
fontSize: 16.0,
fontWeight: FontWeight.bold,
color: Colors.blueGrey),
),
],
),
),
),
),
),
),

Answer 6

#override
Widget build(BuildContext context) {
return Scaffold(
body: StreamBuilder(
stream: Firestore.instance.collection('fortunepool').where('index', isGreaterThanOrEqualTo: 0).orderBy('index').limit(1).snapshots(),
builder: (context, snapshot) {
if (!snapshot.hasData) {
return Container(child: CircularProgressIndicator());
} else {
return ListView.builder(
itemCount: snapshot.data.documents.length,
itemBuilder: (context, index) {
List<DocumentSnapshot> listedQS =
snapshot.data.documents; //listed documents
var random = new Random(); //dart math
for (var i = listedQS.length - 1; i > 0; i--) {
var n = random.nextInt(i + 1);
var temp = listedQS[i];
listedQS[i] = listedQS[n];
listedQS[n] = temp;
}
DocumentSnapshot mypost = listedQS[0];
return Stack(

Answer 7

My code is just like below. I aso updated database as you've indicated above but still white screen
Widget build(BuildContext context) {
return Scaffold(
body: StreamBuilder(
stream: Firestore.instance
.collection('fortunepool')
.where('index', isGreaterThanOrEqualTo: 0)
.orderBy('index')
.limit(1)
.snapshots(),
builder: (context, snapshot) {
if (!snapshot.hasData) {
return Container(child: CircularProgressIndicator());
} else {
return ListView.builder(
itemCount: snapshot.data.documents.length,
itemBuilder: (context, index) {
List<DocumentSnapshot> listedQS =
snapshot.data.documents; //listed documents
DocumentSnapshot mypost = listedQS[0];
return Stack(