validateAddress method
Implementation
String? Function(String?) validateAddress(String? value,
{String? requiredError, String? invalidError}) {
return (String? value) {
if (value == null || value.isEmpty) {
return requiredError ?? 'Please enter an address';
}
// Regular expression to validate address format
final addressRegex = RegExp(r'^[a-zA-Z0-9 ]+$');
if (!addressRegex.hasMatch(value)) {
return invalidError ?? 'Please enter a valid address';
}
return null;
}; // Return null to indicate valid input
}