在flutter和sqflite中，我创建了这个函数来计算colPrix中的总价格。我想计算两个日期（周期时间）之间的总价格，每次想计算总价格时，我应该怎么做？
1/函数计算数据库中的Total（我在其中创建数据库）。
class DatabaseHelper {
static DatabaseHelper _databaseHelper; // Singleton DatabaseHelper
static Database _database; // Singleton Database
String clientTable = 'client_table';
String colId = 'id';
String colNumerotelephone = 'numerotelephone';
String colCode = 'code';
String colPrix = 'prix';
String colPriority = 'priority';
String colColor = 'color';
String colDate = 'date';
DatabaseHelper._createInstance();
factory DatabaseHelper() {
if (_databaseHelper == null) {_databaseHelper = DatabaseHelper._createInstance(); // This is executed only once, singleton object}
return _databaseHelper;
}
Future<Database> get database async {
if (_database == null) { _database = await initializeDatabase();}
return _database;
}
.....
.....
Future claculTotalPeriod (String startDate, String endDate) async {
var totalClientperiod = await database;
var result = await totalClientperiod.rawQuery("SELECT SUM($colPrix) AS TOTAL from $clientTable WHERE $colDate BETWEEN '$startDate' AND '$endDate'");
return result.toList();
}
}2/显示结果
class ClientList extends StatefulWidget {
const ClientList({Key key}) : super(key: key);
@override
State<StatefulWidget> createState() {
return ClientListState();
}
}
class ClientListState extends State<ClientList> {
DatabaseHelper databaseHelper = DatabaseHelper();
List<Client> clientList;
int count = 0;
int axisCount = 2;
double somme_period = 00;
String somme_total_period = "00.00";
String startDate='';
String endDate='';
TextEditingController startdate = TextEditingController();
TextEditingController finishdate = TextEditingController();
void calcul_total_period() async {
var total_sum_period = (await databaseHelper.claculTotalPeriod(startDate, endDate))[0]['$startDate''$endDate'];
setState(() {
somme_period = total_sum_period ?? 00;
somme_total_period = somme.toStringAsFixed(2);
});
}
@override
Widget build(BuildContext context) {
if (clientList == null) {
clientList = [];
updateListView();
}
return Scaffold(
appBar: myAppBar(),
body: clientList.isEmpty
? Container(
color: Colors.white,
child: Center(
child: Padding(
padding: const EdgeInsets.all(16.0),
child: Text('add+',
style: Theme.of(context).textTheme.bodyText2),
),
),
)
: Container(
color: Colors.white,
child: getClientsList(),
),
floatingActionButton: FloatingActionButton(
onPressed: () {
navigateToDetail(Client('', '', '', 3, 0, 0.0), 'new');
},
tooltip: 'add',
shape: const CircleBorder(
side: BorderSide(color: Colors.black, width: 2.0)),
child: const Icon(Icons.add, color: Colors.black),
backgroundColor: Colors.white,
),
bottomNavigationBar: OutlinedButton(
onPressed: () {
showDialog(
...
child: Column(
TextField(
controller: startdate,
decoration: const InputDecoration(
icon: Icon(Icons.calendar_today
),
onTap: () async {
DateTime pickedDate = await showDatePicker(
context: context,
initialDate: DateTime.now(),
firstDate: DateTime(2022,12),
lastDate: DateTime(2026,12));
if (pickedDate != null) {
print(
pickedDate);
String formattedDate =
DateFormat('yyyy-MM-dd').format(pickedDate);
print(
formattedDate); //formatted date output using intl package => 2021-03-16
setState(() {
startdate.text =
formattedDate;
startDate = startdate.text.toString();
});
} else {}
},
),
const SizedBox(height: 20,),
TextField(
controller: finishdate,
decoration: const InputDecoration(
icon: Icon(Icons.calendar_today), //icon of text field
),
onTap: () async {
DateTime pickedDate = await showDatePicker(
context: context,
initialDate: DateTime.now(),
firstDate: DateTime(2022,12),
lastDate: DateTime(2026,12));
if (pickedDate != null) {
print(
pickedDate); //pickedDate output format => 2021-03-10 00:00:00.000
String formattedDate =
DateFormat('yyyy-MM-dd').format(pickedDate);
print(
formattedDate); //formatted date output using intl package => 2021-03-16
setState(() {
finishdate.text =
formattedDate; //set output date to TextField value.
endDate = finishdate.text.toString();
});
} else {}
},
),
const SizedBox(height: 20,),
OutlinedButton(
onPressed: () {
calcul_total_period();
},
child: const Text(' total in period')),
Padding(
padding: const EdgeInsets.all(8.0),
child: Text(
somme_total_period,
style: Theme.of(context).textTheme.headline5,
textAlign: TextAlign.center,
),
),
],
),
),
);
});
},
child: const Text('total')),
);
}
Widget getClientsList() {
return StaggeredGridView.countBuilder(
physics: const BouncingScrollPhysics(),
crossAxisCount: 4,
itemCount: count,
itemBuilder: (BuildContext context, int index) => GestureDetector(
onTap: () {
navigateToDetail(clientList[index], 'edit');
},
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Container(
padding: const EdgeInsets.all(8.0),
decoration: BoxDecoration(
color: colors[clientList[index].color],
border: Border.all(width: 2, color: Colors.black),
borderRadius: BorderRadius.circular(8.0)),
child: Column(
children: <Widget>[
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Expanded(
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Text(
clientList[index].numerotelephone,
style: Theme.of(context).textTheme.bodyText2,
),
),
),
Text(
getPriorityText(clientList[index].priority),
),
],
),
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Expanded(
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Text(
clientList[index].code,
style: Theme.of(context).textTheme.bodyText2,
),
),
),
],
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Row(
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
Expanded(
child: Text(clientList[index].prix.toString() ?? 0,
style: Theme.of(context).textTheme.bodyText1),
)
],
),
),
Row(
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
Text(clientList[index].date,
style: Theme.of(context).textTheme.subtitle2),
])
],
),
),
),
),
staggeredTileBuilder: (int index) => StaggeredTile.fit(axisCount),
mainAxisSpacing: 4.0,
crossAxisSpacing: 4.0,
);
}
void navigateToDetail(Client client, String title) async {
bool result = await Navigator.push(context,
MaterialPageRoute(builder: (context) => ClientDetail(client, title)));
if (result == true) {
updateListView();
}
}
void updateListView() {
final Future<Database> dbFuture = databaseHelper.initializeDatabase();
dbFuture.then((database) {
Future<List<Client>> clientListFuture = databaseHelper.getClientList();
clientListFuture.then((clientList) {
setState(() {
this.clientList = clientList;
count = clientList.length;
});
});
});
}
}
1条答案
按热度按时间aiazj4mn1#
你可以这样做