https://github.com/ajinasokan/flutter_local_auth
local_auth, but with support for devices that doesn't advertise the feature flag PackageManager.FEATURE_FINGERPRINT
https://github.com/ajinasokan/flutter_local_auth
flutter
Last synced: about 1 month ago
JSON representation
local_auth, but with support for devices that doesn't advertise the feature flag PackageManager.FEATURE_FINGERPRINT
- Host: GitHub
- URL: https://github.com/ajinasokan/flutter_local_auth
- Owner: ajinasokan
- License: bsd-3-clause
- Created: 2019-07-03T06:13:29.000Z (almost 6 years ago)
- Default Branch: master
- Last Pushed: 2024-10-31T11:07:43.000Z (7 months ago)
- Last Synced: 2025-04-05T19:51:16.701Z (2 months ago)
- Topics: flutter
- Language: Dart
- Homepage:
- Size: 93.8 KB
- Stars: 21
- Watchers: 0
- Forks: 7
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
# About this fork
Some devices with older versions of Android doesn't advertise the feature flag `PackageManager.FEATURE_FINGERPRINT`. This makes the library think that the device doesn't have finger print sensor. This repo contains a patched version of local_auth lib with support for these devices. This fork also adds a [patch](https://github.com/flutter/plugins/pull/3807) to add an option to force use of only strong biometric authentication.
References:
[https://github.com/flutter/flutter/issues/46227](https://github.com/flutter/flutter/issues/46227)
[https://issuetracker.google.com/issues/37132365](https://issuetracker.google.com/issues/37132365)
## Usage
Add to pubspec:
```yaml
local_auth:
git:
url: https://github.com/ajinasokan/flutter_local_auth
ref: v1.0.0
```
## local_auth
This Flutter plugin provides means to perform local, on-device authentication of
the user.
This means referring to biometric authentication on iOS (Touch ID or lock code)
and the fingerprint APIs on Android (introduced in Android 6.0).
## Usage in Dart
Import the relevant file:
```dart
import 'package:local_auth/local_auth.dart';
```
To check whether there is local authentication available on this device or not, call canCheckBiometrics:
```dart
bool canCheckBiometrics =
await localAuth.canCheckBiometrics;
```
Currently the following biometric types are implemented:
- BiometricType.face
- BiometricType.fingerprint
To get a list of enrolled biometrics, call getAvailableBiometrics:
```dart
List availableBiometrics =
await auth.getAvailableBiometrics();
if (Platform.isIOS) {
if (availableBiometrics.contains(BiometricType.face)) {
// Face ID.
} else if (availableBiometrics.contains(BiometricType.fingerprint)) {
// Touch ID.
}
}
```
We have default dialogs with an 'OK' button to show authentication error
messages for the following 2 cases:
1. Passcode/PIN/Pattern Not Set. The user has not yet configured a passcode on
iOS or PIN/pattern on Android.
2. Touch ID/Fingerprint Not Enrolled. The user has not enrolled any
fingerprints on the device.
Which means, if there's no fingerprint on the user's device, a dialog with
instructions will pop up to let the user set up fingerprint. If the user clicks
'OK' button, it will return 'false'.
Use the exported APIs to trigger local authentication with default dialogs:
The `authenticate()` method uses biometric authentication, but also allows
users to use pin, pattern, or passcode.
```dart
var localAuth = LocalAuthentication();
bool didAuthenticate =
await localAuth.authenticate(
localizedReason: 'Please authenticate to show account balance');
```
To authenticate using biometric authentication only, set `biometricOnly` to `true`.
```dart
var localAuth = LocalAuthentication();
bool didAuthenticate =
await localAuth.authenticate(
localizedReason: 'Please authenticate to show account balance',
biometricOnly: true);
```
If you don't want to use the default dialogs, call this API with
'useErrorDialogs = false'. In this case, it will throw the error message back
and you need to handle them in your dart code:
```dart
bool didAuthenticate =
await localAuth.authenticate(
localizedReason: 'Please authenticate to show account balance',
useErrorDialogs: false);
```
You can use our default dialog messages, or you can use your own messages by
passing in IOSAuthMessages and AndroidAuthMessages:
```dart
import 'package:local_auth/auth_strings.dart';
const iosStrings = const IOSAuthMessages(
cancelButton: 'cancel',
goToSettingsButton: 'settings',
goToSettingsDescription: 'Please set up your Touch ID.',
lockOut: 'Please reenable your Touch ID');
await localAuth.authenticate(
localizedReason: 'Please authenticate to show account balance',
useErrorDialogs: false,
iOSAuthStrings: iosStrings);
```
If needed, you can manually stop authentication for android:
```dart
void _cancelAuthentication() {
localAuth.stopAuthentication();
}
```
### Exceptions
There are 6 types of exceptions: PasscodeNotSet, NotEnrolled, NotAvailable, OtherOperatingSystem, LockedOut and PermanentlyLockedOut.
They are wrapped in LocalAuthenticationError class. You can
catch the exception and handle them by different types. For example:
```dart
import 'package:flutter/services.dart';
import 'package:local_auth/error_codes.dart' as auth_error;
try {
bool didAuthenticate = await local_auth.authenticate(
localizedReason: 'Please authenticate to show account balance');
} on PlatformException catch (e) {
if (e.code == auth_error.notAvailable) {
// Handle this exception here.
}
}
```
## iOS Integration
Note that this plugin works with both Touch ID and Face ID. However, to use the latter,
you need to also add:
```xml
NSFaceIDUsageDescription
Why is my app authenticating using face id?
```
to your Info.plist file. Failure to do so results in a dialog that tells the user your
app has not been updated to use Face ID.
## Android Integration
Note that local_auth plugin requires the use of a FragmentActivity as
opposed to Activity. This can be easily done by switching to use
`FlutterFragmentActivity` as opposed to `FlutterActivity` in your
manifest (or your own Activity class if you are extending the base class).
Update your MainActivity.java:
```java
import android.os.Bundle;
import io.flutter.app.FlutterFragmentActivity;
import io.flutter.plugins.flutter_plugin_android_lifecycle.FlutterAndroidLifecyclePlugin;
import io.flutter.plugins.localauth.LocalAuthPlugin;
public class MainActivity extends FlutterFragmentActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
FlutterAndroidLifecyclePlugin.registerWith(
registrarFor(
"io.flutter.plugins.flutter_plugin_android_lifecycle.FlutterAndroidLifecyclePlugin"));
LocalAuthPlugin.registerWith(registrarFor("io.flutter.plugins.localauth.LocalAuthPlugin"));
}
}
```
OR
Update your MainActivity.kt:
```kotlin
import io.flutter.embedding.android.FlutterFragmentActivity
import io.flutter.embedding.engine.FlutterEngine
import io.flutter.plugins.GeneratedPluginRegistrant
class MainActivity: FlutterFragmentActivity() {
override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
GeneratedPluginRegistrant.registerWith(flutterEngine)
}
}
```
Update your project's `AndroidManifest.xml` file to include the
`USE_FINGERPRINT` permissions:
```xml
```
On Android, you can check only for existence of fingerprint hardware prior
to API 29 (Android Q). Therefore, if you would like to support other biometrics
types (such as face scanning) and you want to support SDKs lower than Q,
_do not_ call `getAvailableBiometrics`. Simply call `authenticate` with `biometricOnly: true`.
This will return an error if there was no hardware available.
## Sticky Auth
You can set the `stickyAuth` option on the plugin to true so that plugin does not
return failure if the app is put to background by the system. This might happen
if the user receives a phone call before they get a chance to authenticate. With
`stickyAuth` set to false, this would result in plugin returning failure result
to the Dart app. If set to true, the plugin will retry authenticating when the
app resumes.
## Getting Started
For help getting started with Flutter, view our online
[documentation](https://flutter.dev/).
For help on editing plugin code, view the [documentation](https://flutter.dev/docs/development/packages-and-plugins/developing-packages#plugin).