1 2 Android FingerprintDialog Sample (Kotlin) 3 ========================================= 4 5 A sample that demonstrates to use registered fingerprints to authenticate the user in your app 6 7 Introduction 8 ------------ 9 10 This sample demonstrates how you can use registered fingerprints in your app to authenticate the 11 user before proceeding some actions such as purchasing an item. 12 13 First you need to create a symmetric key in the Android Key Store using [KeyGenerator][1] 14 which can be only be used after the user has authenticated with fingerprint and pass 15 a [KeyGenParameterSpec][2]. 16 17 By setting [KeyGenParameterSpec.Builder.setUserAuthenticationRequired][3] to true, you can permit 18 the use of the key only after the user authenticate it including when authenticated with the user's 19 fingerprint. 20 21 Then start listening to a fingerprint on the fingerprint sensor by calling 22 [FingerprintManager.authenticate][4] with a [Cipher][5] initialized with the symmetric key created. 23 Or alternatively you can fall back to server-side verified password as an authenticator. 24 25 Once the fingerprint (or password) is verified, the 26 [FingerprintManager.AuthenticationCallback#onAuthenticationSucceeded()][6] callback is called. 27 28 [1]: https://developer.android.com/reference/javax/crypto/KeyGenerator.html 29 [2]: https://developer.android.com/reference/android/security/keystore/KeyGenParameterSpec.html 30 [3]: https://developer.android.com/reference/android/security/keystore/KeyGenParameterSpec.Builder.html#setUserAuthenticationRequired%28boolean%29 31 [4]: https://developer.android.com/reference/android/hardware/fingerprint/FingerprintManager.html#authenticate%28android.hardware.fingerprint.FingerprintManager.CryptoObject,%20android.os.CancellationSignal,%20int,%20android.hardware.fingerprint.FingerprintManager.AuthenticationCallback,%20android.os.Handler%29 32 [5]: https://developer.android.com/reference/javax/crypto/Cipher.html 33 [6]: https://developer.android.com/reference/android/hardware/fingerprint/FingerprintManager.AuthenticationCallback.html#onAuthenticationSucceeded%28android.hardware.fingerprint.FingerprintManager.AuthenticationResult%29 34 35 Pre-requisites 36 -------------- 37 38 - Android SDK 27 39 - Android Support Repository 40 41 Screenshots 42 ------------- 43 44 <img src="screenshots/1-purchase-screen.png" height="400" alt="Screenshot"/> 45 <img src="screenshots/2-fingerprint-dialog.png" height="400" alt="Screenshot"/> 46 <img src="screenshots/3-fingerprint-authenticated.png" height="400" alt="Screenshot"/> 47 <img src="screenshots/4-new-fingerprint-enrolled.png" height="400" alt="Screenshot"/> 48 49 Getting Started 50 --------------- 51 52 This sample uses the Gradle build system. To build this project, use the 53 "gradlew build" command or use "Import Project" in Android Studio. 54 55 Support 56 ------- 57 58 - Google+ Community: https://plus.google.com/communities/105153134372062985968 59 - Stack Overflow: http://stackoverflow.com/questions/tagged/android 60 61 If you've found an error in this sample, please file an issue: 62 https://github.com/googlesamples/android-FingerprintDialog 63 64 Patches are encouraged, and may be submitted by forking this project and 65 submitting a pull request through GitHub. Please see CONTRIBUTING.md for more details. 66 67 License 68 ------- 69 70 Copyright 2017 The Android Open Source Project, Inc. 71 72 Licensed to the Apache Software Foundation (ASF) under one or more contributor 73 license agreements. See the NOTICE file distributed with this work for 74 additional information regarding copyright ownership. The ASF licenses this 75 file to you under the Apache License, Version 2.0 (the "License"); you may not 76 use this file except in compliance with the License. You may obtain a copy of 77 the License at 78 79 http://www.apache.org/licenses/LICENSE-2.0 80 81 Unless required by applicable law or agreed to in writing, software 82 distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 83 WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 84 License for the specific language governing permissions and limitations under 85 the License. 86