我想制作一个奖励积分应用程序，因为我使用了随机函数。
问题是我不知道如何将此号码添加到先前的号码。得到总分。
这是我想要在此处求和的结果。
修改后，我收到此错误
这是我的奖励应用程序的完整代码
rewards.dart
import 'dart:async';
import 'package:fid786/Services/CardScreen.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:fid786/styles.dart';
import 'package:fid786/Services/Clasnumber.dart';
class RewardsScreen extends StatefulWidget {
@override
_RewardsScreenState createState() => _RewardsScreenState();
}
class _RewardsScreenState extends State<RewardsScreen> {
@override
void initState() {
super.initState();
startTimer();
}
startTimer() async{
var duration=Duration(seconds: 4);
return Timer(duration,route);
}
route(){
Navigator.pushReplacement(context,MaterialPageRoute(builder:
(context)=>CardScreen()));
}
@override
Widget build(BuildContext context) {
return Scaffold(
resizeToAvoidBottomPadding: false,body: AnnotatedRegion<SystemUiOverlayStyle>(
value: SystemUiOverlayStyle.light,child: Container(
height: MediaQuery.of(context).size.height,width: MediaQuery.of(context).size.width,decoration: BoxDecoration(
gradient: LinearGradient(
begin: Alignment.topCenter,end: Alignment.bottomCenter,stops: [0.1,0.4,0.7,0.9],colors: [
Color(0xFF3594DD),Color(0xFF4563DB),Color(0xFF5036D5),Color(0xFF5B16D0),],),child: Padding(
padding: EdgeInsets.only(top:80),child: Column(
crossAxisAlignment: CrossAxisAlignment.stretch,children: <Widget>[
Expanded(
flex: 8,child:Container(
height: MediaQuery.of(context).size.height,//height: 600.0,child: PageView(
children: <Widget>[
Padding(
padding: EdgeInsets.symmetric(horizontal: 2),child: Column(
crossAxisAlignment: CrossAxisAlignment.start,children: <Widget>[
Center(
child: ClipRRect(
borderRadius: BorderRadius.circular(50.0),child: Image(
image: AssetImage(
'assets/images/congrats.gif',height: 300.0,width: 300.0,fit: BoxFit.fill,SizedBox(height: 30.0),Text(
' Congratulations,You have Got',style: kTitleStyle,SizedBox(height: 20.0),Center(
child:Text(
Classname.generateRandomNumber().toString(),style: TextStyle(color: Colors.greenaccent,fontWeight: FontWeight.bold,fontSize: 50)),SizedBox(height: 10.0),Center(
child:Text(
' Points ',SizedBox(height: 50.0),Center(
child:Text(
'Earn More Points and Win Prizes ',style:
TextStyle(
color: Colors.yellowaccent,fontSize: 16,fontFamily: 'muso',decoration: TextDecoration.underline),);
}
}
文件CardScreen.dart
import 'package:flutter/material.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:font_awesome_flutter/font_awesome_flutter.dart';
import 'package:fid786/ScanQR/Card_Scanner.dart';
import 'package:fid786/Authentification/LogInScreen.dart';
import 'package:fid786/Services/Clasnumber.dart';
class CardScreen extends StatefulWidget {
@override
_CardScreenState createState()=>_CardScreenState();
}
class _CardScreenState extends State<CardScreen>{
FirebaseAuth auth=FirebaseAuth.instance;
Future<void>logOut() async{
FirebaseUser user=auth.signOut() as FirebaseUser;
return user;
}
@override
void initState() {
super.initState();
}
int points = 0;
int generateNumber() {
int newPoints = Classname.generateRandomNumber();
setState(() {
points += newPoints;
});
return points;
}
@override
Widget build(BuildContext context){
return Scaffold(
backgroundColor:Color(0xffffffff),appBar:AppBar(
backgroundColor: Colors.greenaccent,title:Text("Loyalty Points"),actions: <Widget>[
SizedBox(width:1.0),flatButton.icon(onpressed: (){
logOut();
Navigator.pushReplacement(context,MaterialPageRoute(builder:
(BuildContext context)=>LogInScreen()));
},icon: Icon(Icons.shopping_cart,size: 40.0,color:
Colors.pinkaccent,label: Text("Log Out",style: TextStyle(color:
Colors.pinkaccent),))
],body: StreamBuilder(
stream:Firestore.instance.collection('screen').snapshots(),builder:(context,snapshot){
if(!snapshot.hasData) return Text('');
return Column(
children: <Widget>[
Padding(
padding: EdgeInsets.only(left: 8.0,right: 8.0,top:
40.0),child: Container(
width: MediaQuery.of(context).size.width,height: 80.0,child: Padding(
padding: EdgeInsets.only(top: 8.0,bottom: 8.0),child: Material(
shape: Border.all(width: 2.0,color:
Colors.blueaccent),color: Colors.white,elevation: 18.0,shadowColor: Color(0x802196F3),child: Center(
child: Padding(
padding: EdgeInsets.all(5.0),child: Row(
// mainAxisAlignment:
// MainAxisAlignment.spaceBetween,children: <Widget>[
Text(
snapshot.data.documents[0]['player'],style: TextStyle(
color: Colors.greenaccent,fontSize: 18.0),// mainAxisAlignment:
// MainAxisAlignment.spaceBetween,SizedBox(width:175),Column(
mainAxisAlignment:
MainAxisAlignment.center,children: <Widget>[
Text(
generateNumber().toString(),fontSize: 25)),Text(
'Points',style: TextStyle(
color: Colors.pinkaccent,fontSize: 16.0,fontFamily: 'muso'),)
],);
}
),floatingactionButton: FloatingactionButton(
backgroundColor: Color(0xFFFA7397),child: Icon(
FontAwesomeIcons.listUl,color: Color(0xFFFDDE42),onpressed: () {
Navigator.push(
context,MaterialPageRoute(
builder: (context) => HomePage(),fullscreenDialog: true),);
},)
);
}
}
import 'dart:math';
class Classname{
static int generateRandomNumber() {
List<int> pointvalue = [5,6,7,8,10,15];
return pointvalue[new Random().nextInt(pointvalue.length)];
}
}