I'm new with flutter and wondering is it possible to prefix the number with decimal in textfield. The prefix number is 0.00 and should not delete it.
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So far i have tried something like limited two decimal entry.
CupertinoFormRow(
child: CupertinoTextFormFieldRow(
controller: controller.price,
onChanged: (value) {
controller.calTotal(controller.qty.text, value);
},
placeholder: "Enter item price",
inputFormatters: [
FilteringTextInputFormatter.allow(
RegExp(r'^\d+\.?\d{0,2}')),
],
),
prefix: Text('0.00'),
),
Use currency_text_input_formatter
CupertinoFormRow(
child: CupertinoTextFormFieldRow(
controller: controller.price,
onChanged: (value) {
controller.calTotal(controller.qty.text, value);
},
placeholder: "Enter item price",
inputFormatters: [
CurrencyTextInputFormatter(decimalDigits: 2),
],
),
),
Related
Hi im facing the issue when converting user input to a double example when i input -3 i faced with an FormatException (FormatException: Invalid double -). How can i deal with this? Furthermore how can i prevent user from entering 2 - or . ( 3.3.3 or 3- or --3)as this will also cause error with the double.parse(). Thanks in advance!
TextFormField(
inputFormatters: [FilteringTextInputFormatter.allow(RegExp('[0-9.-]')),],
keyboardType: TextInputType.number,
onChanged:(value) {
setState(() {
fieldPointX = double.parse(value);
});
},
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'X'
),
),
try using this regExp in your TextFormField widget
TextFormField(
keyboardType: const TextInputType.numberWithOptions(
signed: true,
decimal: true,
),
inputFormatters: [
FilteringTextInputFormatter.allow(
RegExp(r'^-?\d*.?\d*')),
],
),
By using TextEditingController in Flutter, I'm trying to force the user to enter a number that starts with zero and then the number 4 or 8, then enter whatever he wants. Like this:
04****** or 08******
What should I do?
My code:
TextFormField(
maxLength: 10,
controller: _inputdat,
inputFormatters: [ FilteringTextInputFormatter.digitsOnly,],
keyboardType: TextInputType.number),
ElevatedButton(
......
onPressed: () async {
if (_inputdat.text.length < 10
|| !RegExp(r'^[0][8/4/2]{1}[0-9]{8}$').hasMatch(value))
{
ScaffoldMessenger.of(context).showSnackBar(const SnackBar(
backgroundColor: Color(0xff446d74),
content: Text(
"Error",
)));
What's wrong with my code? I got the error: Undefined name 'value'.
You can use https://pub.dev/packages/mask_text_input_formatter and do something like this:
var maskFormatter = new MaskTextInputFormatter(
mask: '0*########',
filter: { "*": RegExp(r'[48]'), "#": RegExp(r'[0-9]') },
type: MaskAutoCompletionType.lazy
);
and then pass maskFormatter to your text filed
TextField(inputFormatters: [maskFormatter])
Use this regex in the TextFormFiled validator r'^0[48][0-9]{7}$'
If you want to specify a specific number in total you can specify it in this part [0-9]{7} instead of seven you can choose different number.
This regex has in total of 9 numbers:
start with Zero 0
Second choose one 4 or 8 [48]
Third choose any 7 number [0-9]{7}
The validator should look something like this:
validator: (value) {
if (value!.isEmpty || !RegExp(r'^0[48][0-9]{7}$').hasMatch(value)) {
return "error message";
} else {
return null;
}
},
initialize a form key like below:
final formKey = GlobalKey<FormState>();
Full code:
Form(
autovalidateMode: AutovalidateMode.onUserInteraction,
key: formKey,
child: Column(
children: [
TextFormField(
validator: (value) {
if (value!.isEmpty || !RegExp(r'^0[48][0-9]{7}$').hasMatch(value)) {
return "error message";
} else {
return null;
}
},
decoration: const InputDecoration(
errorMaxLines: 2, // specify how many error lines you want
border: OutlineInputBorder(),
labelText: 'number',
),
maxLength: 10,
controller: _inputdat,
inputFormatters: [FilteringTextInputFormatter.digitsOnly],
keyboardType: TextInputType.number),
ElevatedButton(
onPressed: () {
if (formKey.currentState!.validate()) {
// do something like a function or toast message etc...
}
},
child: const Text('Confirm'),
),
],
),
),
I have TextFormField and i want to allow only number and 1 "." and also only 2 digit after decimal.
I have set below things :
keyboardType: TextInputType.number,
inputFormatters: [FilteringTextInputFormatter.allow((RegExp("[0-9.0-9]"))) ],
But this one allows me to enter multiple "." and unlimited after decimal.
I want to allow digits and only 1 "." and only 2 digits after "."
How can i do that?
I got it. It should be
keyboardType: TextInputType.number,
inputFormatters: [FilteringTextInputFormatter.allow(RegExp(r'^(\d+)?\.?\d{0,2}')), FilteringTextInputFormatter.allow(RegExp(r'^\d+\.?\d*')) ],
You can use the
onChanged : (val) {
// your logic here
}
eg: -
TextFormField(
controller: numberController,
decoration: const InputDecoration(
label: Text(
'Enter Number'
),
),
keyboardType: TextInputType.number,
onChanged: (val){
if(val.indexOf('.') != val.lastIndexOf('.')){
numberController.text = val.substring(0, val.length -1);
showDialog(context: context, builder: (ctx) => AlertDialog(
title: const Text('Please enter valid number'),
actions: [
IconButton(
onPressed: (){
Navigator.of(context).pop();
},
icon: const Icon(Icons.close))
],
));
}
},
),
to check the values dynamically. You can use, control and change your values and fields there.
or you can use the simplest solution from Alex
I want the field to allow the entry of numbers and the + sign only but all I could do was make the field allow the entry of numbers only and I couldn't make it accept the + sign
here is my code
TextField(
inputFormatters: [
FilteringTextInputFormatter.allow(
RegExp(
"[0-9]",
),
),
],
),
TextField(
inputFormatters: [
FilteringTextInputFormatter.allow(
RegExp(
r'^\+?\d*',
),
),],
)
This will accept an optional + sign at the begining and the rest are numbers. The same as international phone numbers.
TextField(
keyboardType:TextInputType.numberWithOptions(decimal:true,signed:true),
inputFormatters: [
FilteringTextInputFormatter.allow(RegExp('[0-9.,]+')),
],
)
,
just add this.
I want a user can input no more than 100 in my textfield.
If a user put more than 100 --let's say 123--, the text will show 100 instead of 123.
here is my code
TextField(
controller: qtyController,
keyboardType: TextInputType.number,
onTap: () => qtyController.text = '',
inputFormatters: [FilteringTextInputFormatter. digitsOnly,
LengthLimitingTextInputFormatter(3),
],
textAlign: TextAlign.center,
style: TextStyle(color: Colors.white),
)
You can use the onChanged callback to listen to the changes
TextField(
controller: qtyController,
keyboardType: TextInputType.number,
onTap: () => qtyController.text = '',
onChanged: (val){
if (val.isNotEmpty) {
if(int.parse(val)>=100) {
qtyController.text = "100";
}
}
},
inputFormatters: [
FilteringTextInputFormatter.digitsOnly,
LengthLimitingTextInputFormatter(3),
],
textAlign: TextAlign.center,
style: TextStyle(color: Colors.white),
)
The simplest approach is to supply an onChanged() callback to a TextField or a TextFormField. Whenever the text changes, the callback is invoked.
A more powerful, but more elaborate approach, is to supply a TextEditingController as the controller property of the TextField or a TextFormField.
Details on here:https://docs.flutter.dev/cookbook/forms/text-field-changes
You can use the maxLength property to set the maximum characters allowed in the TextField. Read more about it here.