Text field update doesn't work with flutter_masked_text - dart

Question

I'm creating a app, where one of the features is update text fields
based on changes of another text fields.
The fields are about product prices in: Dollar, Euro, Real.
If the price in Dollar are changed by user, the Euro and Real price are too, and so on...
The problem is, if I use the normal TextEditingController all works well, but if I use MoneyMaskedTextController from the flutter_masked_text package, the updating stops.
Could any one test my code and to answer me why the updating stops with the MoneyMaskedTextController?
To test, don't forget to install the flutter_masked_text: ^0.8.0 in your pubspec.yaml.
If I can not use the flutter_masked_text for it, how could I use masks and update text fields?
Thank you.
import 'package:flutter/material.dart';
import 'package:flutter_masked_text/flutter_masked_text.dart';
void main() {
runApp(MaterialApp(
home: ProductType(),
));
}
class ProductType extends StatefulWidget {
_ProductTypeScreen createState() => _ProductTypeScreen();
}
class _ProductTypeScreen extends State<ProductType> {
#override
Widget build(BuildContext context) {
double dollarRate = 3.70;
double euroRate = 4.20;
//Normal controllers
/* final ctrl_real = TextEditingController();
final ctrl_dollar = TextEditingController();
final ctrl_euro = TextEditingController();*/
//Money Mask controllers
final ctrl_real = MoneyMaskedTextController();
final ctrl_dollar = MoneyMaskedTextController();
final ctrl_euro = MoneyMaskedTextController();
void change_real(String text) {
double real = double.parse(text);
ctrl_dollar.text = (real / dollarRate).toString();
ctrl_euro.text = (real / euroRate).toString();
}
void change_dollar(String text) {
double dolar = double.parse(text);
ctrl_real.text = (dolar * dollarRate).toString();
ctrl_euro.text = (dolar * dollarRate / euroRate).toString();
}
void change_euro(String text) {
double euro = double.parse(text);
ctrl_real.text = (euro * euroRate).toString();
ctrl_dollar.text = (euro * euroRate / dollarRate).toString();
}
return Scaffold(
body: SingleChildScrollView(
child: Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Container(
width: 160.0,
height: 200.0,
padding: EdgeInsets.all(20.0),
child: TextField(
controller: ctrl_euro,
decoration: InputDecoration(
labelText: "Euro price",
prefixText: "€"),
onChanged: change_euro,
keyboardType: TextInputType.numberWithOptions(
decimal: true),
)),
Container(
width: 160.0,
height: 200.0,
padding: EdgeInsets.all(20.0),
child: TextField(
controller: ctrl_dollar,
decoration: InputDecoration(
labelText: "Dolar price",
prefixText: "US\$"),
onChanged: change_dollar,
keyboardType: TextInputType.numberWithOptions(
decimal: true),
)),
Container(
width: 160.0,
height: 200.0,
padding: EdgeInsets.all(20.0),
child: TextField(
controller: ctrl_real,
decoration: InputDecoration(
labelText: "Real price",
prefixText: "R\$"),
onChanged: change_real,
keyboardType: TextInputType.numberWithOptions(
decimal: true),
)),
]
)
)
);
}
}

Answer 1

If you check the value received on each method , you will see a comma "," in your decimal values.
void change_real(String text) {
print("Text : $text");
}
so every time you try to parse those values , it crashes here:
double real = double.parse(text);
One way to solve your issue just change the decimalSeparator to '.' , like this:
final ctrl_real = MoneyMaskedTextController(decimalSeparator: ".");
final ctrl_dollar = MoneyMaskedTextController(decimalSeparator: ".");
final ctrl_euro = MoneyMaskedTextController(decimalSeparator: ".");