BioPass ID Fingerprint SDK Flutter

Latest Version

May 18, 2023 - 0.0.10

Table of Contents

Quick Start Guide

First, you will need a license key to use the SDK. To get your license key contact us through our website BioPass ID.

Check out our official documentation for more in depth information on BioPass ID.

1. Prerequisites:

Android iOS
Support SDK 21+ iOS 13+ 
- A device with a camera
- License key
- Internet connection is required to verify the license

2. Installation

First, add fingerprint_sdk_flutter as a dependency in your pubspec.yaml file.

Android

Change the minimum Android sdk version to 21 (or higher) in your android/app/build.gradle file.

minSdkVersion 21

Change the compile Android sdk version to 31 (or higher) in your android/app/build.gradle file.

compileSdkVersion 31

iOS

Requires iOS 13.0 or higher.

Add to the ios/Info.plist:

  • the key Privacy - Camera Usage Description and a usage description.

If editing Info.plist as text, add:

<key>NSCameraUsageDescription</key>
<string>Your camera usage description</string>

Then go into your project's ios folder and run pod install.

# Go into ios folder
$ cd ios

# Install dependencies
$ pod install

3. How to use

To call Fingerprint in your Flutter project is as easy as follow:

import 'package:flutter/material.dart';
import 'package:fingerprint_sdk_flutter/fingerprint_sdk_flutter.dart';
import 'dart:typed_data';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Fingerprint Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key});

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final config = FingerprintConfig(
    licenseKey: 'your-license-key',
    captureType: FingerprintCaptureType.LEFT_HAND_FINGERS,
    outputType: FingerprintOutputType.CAPTURE_AND_SEGMENTATION,
    nFingersToCapture: 4,
    showStatusView: true,
    showDistanceIndicatorView: true,
    showFingersIndicatorView: true,
  );

  IFingerprintCaptureListener listener() => FingerprintCaptureListener(
        onFingerCapture: (List<Uint8List> images) async {
          print('Demo App - onFingerCapture: ${images[0][0]}');
        },
        onCaptureCanceled: () async {
          print('Demo App: onCaptureCanceled');
        },
        onStatusChanged: (FingerprintCaptureState state) async {
          print('Demo App - onStatusChanged: $state');
        },
        onFingerDetected: (List<Rect> displayFingerRects) async {
          print('Demo App - onFingerDetected: $displayFingerRects');
        },
        onClassificationChanged: (String classif) async {
          print('Demo App - onClassificationChanged: $classif');
        },
      );

  void openCamera() async {
    await Fingerprint.buildCameraView(
      config: config,
      listener: listener(),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Fingerprint Demo'),
      ),
      body: Center(
        child: ElevatedButton(
          onPressed: openCamera,
          child: const Text('Capture Fingers'),
        ),
      ),
    );
  }
}

4. FingerCaptureListener

You can set a custom listener to receive captured fingers as well as finger rectangles and monitor the current capture status, among other features. You can write you own listener following this example:

IFingerprintCaptureListener listener() => FingerprintCaptureListener(
        onFingerCapture: (List<Uint8List> images) async {
          print('onFingerCapture: $images');
        },
        onCaptureCanceled: () async {
          print('onCaptureCanceled');
        },
        onStatusChanged: (FingerprintCaptureState state) async {
          print('onStatusChanged: $state');
        },
        onFingerDetected: (List<Rect> displayFingerRects) async {
          print('onFingerDetected: $displayFingerRects');
        },
        onClassificationChanged: (String classif) async {
          print('onClassificationChanged: $classif');
        },
      );

FingerprintCaptureState (enum)

Name
FingerprintCaptureState.NO_DETECTION
FingerprintCaptureState.MISSING_FINGERS
FingerprintCaptureState.TOO_CLOSE
FingerprintCaptureState.TOO_FAR
FingerprintCaptureState.OK
FingerprintCaptureState.STOPPED
FingerprintCaptureState.PROCESSING
FingerprintCaptureState.MODEL_NOT_FOUND

5. LicenseKey

First, you will need a license key to use the SDK. To get your license key contact us through our website BioPass ID.

To use Fingerprint Capture you need a license key. To set the license key needed is simple as setting another attribute. Simply doing:

final config = FingerprintConfig(licenseKey: 'your-license-key');

Configs

FingerprintConfig

Variable name Type Default value
licenseKey String ''
showStatusView bool true
showDistanceIndicatorView bool true
showFingersIndicatorView bool true
nFingersToCapture int 4
captureType FingerprintCaptureType FingerprintCaptureType.LEFT_HAND_FINGERS
outputType FingerprintOutputType FingerprintOutputType.CAPTURE_AND_SEGMENTATION

FingerprintCaptureType (enum)

Name
FingerprintCaptureType.RIGHT_HAND_FINGERS
FingerprintCaptureType.LEFT_HAND_FINGERS
FingerprintCaptureType.THUMBS

FingerprintOutputType (enum)

Name
FingerprintOutputType.ONLY_CAPTURE
FingerprintOutputType.CAPTURE_AND_SEGMENTATION

Changelog

0.0.10

  • Documentation update;
  • Focus adjustments for Android.

0.0.9

  • Documentation update;
  • License functionality fix for iOS.

0.0.8

  • Documentation update.

0.0.7

  • Documentation update;
  • Improved license functionality for iOS.

0.0.6

  • Finger capture;
  • Fingers segmentation;
  • Parameterizable distance, status and fingers indicators.
  • Documentation update;
  • dlib bug fix;
  • New licensing feature;
  • Finger indicator fix.

Libraries

fingerprint_sdk_flutter