我在抖动中构建了一个EMI计算器，但结果显示为1250568.00，但希望显示为N$ 1,250,568.00
我尝试了intl软件包，但在Text(f.format(_tiResults)),上遇到了错误，如解释如何实现。还尝试了MoneyMask软件包，但无济于事。
import 'package:homenet/pages/home_page.dart';
import 'dart:math';
class MyHomePage extends StatefulWidget {
@override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
List _durationTypes = ['Month(s)', 'Year(s)'];
String _durationType = "Year(s)";
String _miResult = "";
String _tiResult = "";
String _tcResult = "";
bool _switchValue = true;
final TextEditingController _principalAmount = TextEditingController();
final TextEditingController _interestRate = TextEditingController();
final TextEditingController _loanDuration = TextEditingController();
_onClear(){
setState(() {
_principalAmount.text = "";
_interestRate.text = "";
_loanDuration.text = "";
_miResult = "";
_tiResult = "";
_tcResult = "";
});
}
@override
Widget build(BuildContext context) {
return new Scaffold(
resizeToAvoidBottomPadding: false,
appBar: AppBar(
backgroundColor: new Color(0xFFFA983A),
title: InkWell(
onTap: (){
Navigator.push(context,
MaterialPageRoute(builder: (context) => new HomePage()));},
child: Image.asset(
'assets/images/logo_white.png',
fit: BoxFit.cover,
),
),
elevation: 0.0,
centerTitle: true,
actions: <Widget>[
new IconButton(
icon: new Icon(Icons.cancel, size: 30,),
onPressed: () {
_onClear();
},
),
],
),
body: Center(
child: Container(
margin: EdgeInsets.all(24),
child: Column(
children: <Widget>[
Container(
child: TextField(
cursorColor: Color(0xFFFA983A),
controller: _principalAmount,
decoration:
InputDecoration(
icon: Icon(Icons.monetization_on),
border: OutlineInputBorder(
borderRadius: BorderRadius.circular(25),
gapPadding: 5),
labelText: "Enter Principal Amount"),
keyboardType: TextInputType.numberWithOptions(),
),
),
SizedBox(
height: 12,
),
Container(
child: TextField(
cursorColor: Color(0xFFFA983A),
controller: _interestRate,
decoration:
InputDecoration(
icon: Icon(Icons.show_chart),
border: OutlineInputBorder(
borderRadius: BorderRadius.circular(25),
gapPadding: 5),
labelText: "Interest Rate per Annum %"),
keyboardType: TextInputType.numberWithOptions(),
),
),
SizedBox(
height: 12,
),
Row(
children: <Widget>[
Flexible(
flex: 3,
child: Container(
child: TextField(
cursorColor: Color(0xFFFA983A),
controller: _loanDuration,
decoration: InputDecoration(
icon: Icon(Icons.date_range),
border: OutlineInputBorder(
borderRadius: BorderRadius.circular(25),
gapPadding: 5),
labelText: "Loan Duration"),
keyboardType: TextInputType.numberWithOptions(),
),
),
),
// TODO: ========= SWITCH ================
Flexible(
flex: 1,
child: Column(
children: <Widget>[
Text(
_durationType,
style: TextStyle(
fontWeight: FontWeight.bold,
),
),
Switch(
activeColor: Color(0xFFFA983A),
value: _switchValue,
onChanged: (bool value) {
print(value);
if (value) {
_durationType = _durationTypes[1];
} else {
_durationType = _durationTypes[0];
}
setState(() {
_switchValue = value;
});
}),
],
),
),
],
),
SizedBox(
height: 12,
),
// TODO: ============== Button ============
Flexible(
child: FlatButton(
padding: EdgeInsets.fromLTRB(48, 8, 48, 8),
onPressed: _handleCalculation,
child: Text(
"CALCULATE",
style: TextStyle(color: Colors.white),
),
color: Color(0xFFFA983A),
),
),
SizedBox(
height: 12,
),
// TODO: Results Widget =====================================
monthlyInstalmentsResult(_miResult),
SizedBox(
height: 12,
),
totalInterestResult(_tiResult),
SizedBox(
height: 12,
),
totalCostResult(_tcResult),
SizedBox(
height: 12,
),
Container(
child: Text(
"Disclaimer* This is just an approximate amount"
"and in no way reflect the exact figures, please consult your bank.",
style: TextStyle(
color: Colors.grey,
fontSize: 10,
),
),
),
],
),
),
),
);
}
void _handleCalculation() {
// TODO: Amortization
// TODO: A = Payment amount per period
// TODO: P = Initial Principal (Loan Amount)
// TODO: r = interest Rate
// TODO: n = Total number of payments
double A = 0.0;
double I = 0.0;
double T = 0.0;
double P = double.parse(_principalAmount.text);
double r = double.parse(_interestRate.text) / 12 / 100;
int n = _durationType == "Year(s)"
? int.parse(_loanDuration.text) * 12
: int.parse(_loanDuration.text);
A = (P * r * pow((1 + r), n) / (pow((1 + r), n) - 1));
T = (A * n);
I = (T - P);
_miResult = A.toStringAsFixed(2);
setState(() {});
_tiResult = I.toStringAsFixed(2);
setState(() {});
_tcResult = T.toStringAsFixed(2);
setState(() {});
}
Widget monthlyInstalmentsResult(miResults) {
// var f = new NumberFormat("#,###,###.0#");
// var f = new NumberFormat("###.0#", "en_US");
bool canShow = false;
String _miResults = miResults;
if (_miResults.length > 0) {
canShow = true;
}
return Container(
child: canShow
? Row(
children: <Widget>[
Text(
"Monthly Instalments: ",
style: TextStyle(
color: Colors.grey,
fontSize: 18,
),
),
Text(
"N\$ ",
style: TextStyle(
color: Color(0xFFFA983A),
fontSize: 24,
fontWeight: FontWeight.bold,
),
),
Text(
_miResult,
style: TextStyle(
color: Color(0xFFFA983A),
fontSize: 24,
fontWeight: FontWeight.bold,
),
)
],
)
: Row());
}
Widget totalInterestResult(tiResults) {
bool canShow = false;
String _miResults = tiResults;
if (_miResults.length > 0) {
canShow = true;
}
return Container(
child: canShow
? Row(
children: <Widget>[
Text(
"Total Interest: ",
style: TextStyle(
color: Colors.grey,
fontSize: 18,
),
),
Text(
"N\$ ",
style: TextStyle(
color: Color(0xFFFA983A),
fontSize: 24,
fontWeight: FontWeight.bold,
),
),
Text(
_tiResult,
style: TextStyle(
color: Color(0xFFFA983A),
fontSize: 24,
fontWeight: FontWeight.bold,
),
)
],
)
: Row());
}
Widget totalCostResult(tcResults) {
bool canShow = false;
String _miResults = tcResults;
if (_miResults.length > 0) {
canShow = true;
}
return Container(
child: canShow
? Row(
children: <Widget>[
Text(
"Total Cost: ",
style: TextStyle(
color: Colors.grey,
fontSize: 18,
),
),
Text(
"N\$ ",
style: TextStyle(
color: Color(0xFFFA983A),
fontSize: 24,
fontWeight: FontWeight.bold,
),
),
Text(
_tcResult,
style: TextStyle(
color: Color(0xFFFA983A),
fontSize: 24,
fontWeight: FontWeight.bold,
),
)
],
)
: Row());
}
}
该代码可以完全复制，就像我在我的应用程序中一样。...我希望结果（miResults，tiResults和tcResults以财务/货币格式显示。谢谢。
答案 0 :(得分：2)
尝试一下：
void _handleCalculation() {
// TODO: Amortization
// TODO: A = Payment amount per period
// TODO: P = Initial Principal (Loan Amount)
// TODO: r = interest Rate
// TODO: n = Total number of payments
double A = 0.0;
double I = 0.0;
double T = 0.0;
double P = double.parse(_principalAmount.text);
double r = double.parse(_interestRate.text) / 12 / 100;
int n = _durationType == "Year(s)"
? int.parse(_loanDuration.text) * 12
: int.parse(_loanDuration.text);
A = (P * r * pow((1 + r), n) / (pow((1 + r), n) - 1));
T = (A * n);
I = (T - P);
NumberFormat format = NumberFormat('#,###,###.00');
setState(() {
_miResult = format.format(A);
_tiResult = format.format(I);
_tcResult = format.format(T);
});
}