I am using the Flutter local_auth plugin, biometrics works fine but Pincode/pattern doesn't provide authentication. I found if I remove my fingerprints from my mobile then Pincode and pattern authentication works but I need to input 2 times. The library seems correct but couldn't get a proper hold on the reason for this strange behaviour. Can anyone suggest?
Moreover, can we use a custom UI for the authentication, like how it is in WhatsApp?
local_auth_api.dart:
import 'package:flutter/services.dart';
import 'package:local_auth/local_auth.dart';
import 'package:local_auth/auth_strings.dart';
class LocalAuthApi {
static final _auth = LocalAuthentication();
static const iosStrings = IOSAuthMessages(
cancelButton: 'cancel',
goToSettingsButton: 'settings',
goToSettingsDescription: 'Please set up your Touch ID.',
lockOut: 'Please reenable your Touch ID');
static const androidStrings = AndroidAuthMessages(
cancelButton: 'cancel',
goToSettingsButton: 'settings',
goToSettingsDescription: 'Please set up your Touch ID.',
signInTitle: 'User Authorization Required',
);
static Future<bool> hasBiometrics() async {
try {
return await _auth.canCheckBiometrics;
} on PlatformException catch (e) {
return false;
}
}
static Future<List<BiometricType>> getBiometrics() async {
try {
return await _auth.getAvailableBiometrics();
} on PlatformException catch (e) {
return <BiometricType>[];
}
}
static Future<bool> authenticate() async {
try {
return await _auth.authenticate(
localizedReason: 'Scan your Fingerprint to Authenticate',
useErrorDialogs: true,
sensitiveTransaction: true,
stickyAuth: true,
iOSAuthStrings: iosStrings,
androidAuthStrings: androidStrings
);
} on PlatformException catch (e) {
print(e);
return false;
}
}
}
lock_screen.dart
import 'package:xyz/resources/constants.dart';
import 'package:xyz/src/services/local_auth_api.dart';
import 'package:flutter/material.dart';
class LockScreen extends StatefulWidget{
const LockScreen({Key? key}) : super(key: key);
@override
_LockScreenState createState() => _LockScreenState();
}
class _LockScreenState extends State<LockScreen>{
@override
void initState() {
super.initState();
authenticate();
}
authenticate() async {
bool isAuthenticated = false;
while(true){
isAuthenticated = await LocalAuthApi.authenticate();
if (isAuthenticated) {
print(isAuthenticated);
break;
}
}
print("unlocked");
}
@override
Widget build(BuildContext context) {
Size size = MediaQuery.of(context).size;
double screenHeight = size.height;
double screenWidth = size.width;
return Scaffold(
backgroundColor: primaryColor,
body: Center(
)
);
}
}
Response:
E/BiometricFragment(19568): Not launching prompt. Client activity was null.