aplicacion_movil_syp/lib/memorias_calculo/widgets/formatters.dart

import 'package:flutter/services.dart';

class DecimalTextInputFormatter extends TextInputFormatter{
  @override
  TextEditingValue formatEditUpdate(TextEditingValue oldValue, TextEditingValue newValue) {
    final regExp = RegExp(r"^\d*\.?\d*");
    String newString = regExp.stringMatch(newValue.text) ?? "";
    return newString == newValue.text ? newValue : oldValue;
  }
}

class IntegerTextInputFormatter extends TextInputFormatter{
  @override
  TextEditingValue formatEditUpdate(TextEditingValue oldValue, TextEditingValue newValue) {
    final regExp = RegExp(r"^[0-9]*$");
    String newString = regExp.stringMatch(newValue.text) ?? "";
    return newString == newValue.text ? newValue : oldValue;
  }
}