setCountry method
Implementation
void setCountry(CountryModel? newCountry) {
clear();
selectedCountry = newCountry;
maskFormatter.updateMask(
mask: selectedCountry?.format,
filter: {'.': RegExp(r'[0-9]')},
newValue: TextEditingValue(text: selectedCountry?.currentAreaCode ?? ''),
);
text = maskFormatter.maskText(newCountry?.currentAreaCode ?? '');
notifyListeners();
}