Hi Guys,
In this code below, I want users to be able to vote only once. I am having difficulty in doing this. Please is there anybody here that can help? I use dart/flutter and firestore as backend.
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:compuvote/models/finance_model.dart';
import 'package:compuvote/routes/home_page.dart';
import 'package:compuvote/routes/transitionroute.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:flutter/material.dart';
import 'package:charts_flutter/flutter.dart' as charts;
class FinanceResult extends StatefulWidget {
@override
_FinanceResultState createState() {
return _FinanceResultState();
}
}
class _FinanceResultState extends State<FinanceResult> {
List<charts.Series<Record, String>> _seriesBarData;
List<Record> mydata;
_generateData(mydata) {
_seriesBarData = List<charts.Series<Record, String>>();
_seriesBarData.add(
charts.Series(
domainFn: (Record record, _) => record.name.toString(),
measureFn: (Record record, _) => record.votes,
//colorFn: (Record record, _) => record.color,
id: 'Record',
data: mydata,
// Set a label accessor to control the text of the arc label.
labelAccessorFn: (Record row, _) => '${row.name}: ${row.votes}',
colorFn: (_, __) => charts.MaterialPalette.cyan.shadeDefault,
fillColorFn: (_, __) => charts.MaterialPalette.transparent,
),
);
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Finance Result'),
leading: IconButton(
icon: Icon(Icons.home),
onPressed: () {
Navigator.push(context, TransitionPageRoute(widget: HomePage()));
},
),
),
body: Container(
color: Colors.grey.shade100,
child: _buildBody(context),
));
}
Widget _buildBody(BuildContext context) {
return Column(
children: <Widget>[
StreamBuilder<QuerySnapshot>(
stream: Firestore.instance.collection('finance').snapshots(),
builder: (context, snapshot) {
if (!snapshot.hasData) {
return Center(
child: LinearProgressIndicator(
valueColor: AlwaysStoppedAnimation(
Theme.of(context).primaryColor,
),
),
);
} else {
List<Record> finance = snapshot.data.documents
.map((documentSnapshot) =>
Record.fromMap(documentSnapshot.data))
.toList();
return _buildChart(context, finance);
}
},
),
],
);
}
Widget _buildChart(BuildContext context, List<Record> recorddata) {
mydata = recorddata;
_generateData(mydata);
return Padding(
padding: EdgeInsets.all(8.0),
child: Container(
width: MediaQuery.of(context).size.width,
height: MediaQuery.of(context).size.height / 1.2,
child: Center(
child: Column(
children: <Widget>[
/*
* Text(
'Result for Finance',
style: TextStyle(fontSize: 24.0, fontWeight: FontWeight.bold),
),
* */
SizedBox(
height: 10.0,
),
Expanded(
child: charts.PieChart(
_seriesBarData,
animate: true,
animationDuration: Duration(seconds: 3),
//For adding labels to the chart
defaultRenderer: new charts.ArcRendererConfig(
strokeWidthPx: 2.0,
arcWidth: 100,
arcRendererDecorators: [
// <-- add this to the code
charts.ArcLabelDecorator(
labelPosition: charts.ArcLabelPosition.auto,
labelPadding: 3,
showLeaderLines: true,
insideLabelStyleSpec: charts.TextStyleSpec(
color: charts.Color.white,
fontSize: 12,
),
outsideLabelStyleSpec: charts.TextStyleSpec(
color: charts.Color.black,
fontSize: 12,
),
),
]),
/*
* behaviors: [
new charts.DatumLegend(
entryTextStyle: charts.TextStyleSpec(
color: charts.MaterialPalette.purple.shadeDefault,
fontSize: 18),
)
],
* */
),
),
Container(
width: MediaQuery.of(context).size.width / 3.5,
height: 1,
color: Colors.black38,
),
Expanded(
child: Scaffold(
backgroundColor: Colors.grey.shade100,
body: _castVote(context),
),
),
],
),
),
),
);
}
Widget _castVote(BuildContext context) {
return StreamBuilder<QuerySnapshot>(
stream: Firestore.instance.collection('finance').snapshots(),
builder: (context, snapshot) {
if (!snapshot.hasData)
return Center(
child: LinearProgressIndicator(
valueColor: AlwaysStoppedAnimation(
Theme.of(context).primaryColor,
),
),
);
return _buildList(context, snapshot.data.documents);
},
);
}
Widget _buildList(BuildContext context, List<DocumentSnapshot> snapshot) {
return ListView(
padding: const EdgeInsets.only(top: 20.0),
// ignore: missing_return
children: snapshot.map((data) => _buildListItem(context, data)).toList(),
);
}
Widget _buildListItem(BuildContext context, DocumentSnapshot data) {
final record = Record.fromSnapshot(data);
return Padding(
key: ValueKey(record.name),
padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 8.0),
child: Card(
elevation: 2,
child: Container(
decoration: BoxDecoration(
border: Border.all(color: Colors.grey.shade100),
borderRadius: BorderRadius.circular(5.0),
),
child: ListTile(
title: Text(record.name),
trailing: Text(record.votes.toString()),
onTap: () => record.reference.updateData({'votes': record.votes + 1}),
),
),
),
);
}
}