Bespoke Android App Developers: Biometric Library

Bespoke Android App Developers: Biometric Library

Android provides a Biometric Library as part of its AndroidX Library package, which allows developers to add biometric authentication to their Android apps easily. The Biometric Library provides a standardized way to use biometric authentication, such as fingerprint or face recognition, across all Android devices.

To use the Biometric Library in your app, you must add the following dependency to your app's build.gradle file:

implementation 'androidx.biometric:biometric:1.2.0'

After adding the dependency, you can start using the Biometric Library. Here is an example code snippet that demonstrates how to use the Biometric Library to authenticate a user using fingerprint:

BiometricPrompt.PromptInfo promptInfo = new BiometricPrompt.PromptInfo.Builder() .setTitle("Title for the authentication dialog") .setSubtitle("Subtitle for the authentication dialog") .setDescription("Description for the authentication dialog") .setNegativeButtonText("Cancel") .build(); BiometricPrompt biometricPrompt = new BiometricPrompt(this, executor, new BiometricPrompt.AuthenticationCallback() { @Override public void onAuthenticationSucceeded( BiometricPrompt.AuthenticationResult result) { // User authentication succeeded } @Override public void onAuthenticationFailed() { // User authentication failed } }); biometricPrompt.authenticate(promptInfo);

In this example, we create a BiometricPrompt.PromptInfo object that specifies the title, subtitle, and description for the authentication dialog. We also set the negative button text to "Cancel". We then create a BiometricPrompt object, passing in an Executor object and an AuthenticationCallback object. Finally, we call the authenticate method on the BiometricPrompt object, passing in the PromptInfo object.

When the authenticate method is called, the Biometric Library displays an authentication dialog to the user. If the user successfully authenticates using their fingerprint, the onAuthenticationSucceeded method is called. If the user fails to authenticate or cancels the authentication dialog, the onAuthenticationFailed method is called.

Android provides a biometric library that allows developers to easily integrate biometric authentication into their apps. This library supports several biometric authentication methods, including fingerprint, face, and iris recognition.

To use the biometric library in your app, you need to first check if the device supports biometric authentication using the BiometricManager class. You can then create an instance of the BiometricPrompt class and set the prompt message, title, and other parameters.

Next, you need to implement the BiometricPrompt.AuthenticationCallback interface to handle the authentication result. The interface provides methods for handling success, failure, and other events.

Once you have implemented the callback interface, you can call the authenticate method of the BiometricPrompt instance to initiate the authentication process. The library will handle the biometric authentication and return the result to your callback implementation.

Here's some sample code that shows how to use the biometric library to authenticate a user using their fingerprint:

BiometricManager biometricManager = BiometricManager.from(context); if (biometricManager.canAuthenticate() == BiometricManager.BIOMETRIC_SUCCESS) { BiometricPrompt biometricPrompt = new BiometricPrompt.Builder(context) .setTitle("Authenticate with fingerprint") .setSubtitle("Place your finger on the sensor to authenticate") .setNegativeButton("Cancel", context.getMainExecutor(), (dialogInterface, i) -> {}) .build(); biometricPrompt.authenticate(new BiometricPrompt.PromptInfo.Builder() .setDescription("Confirm your identity using your fingerprint") .setNegativeButtonText("Cancel") .build()); } else { // Biometric authentication is not available on this device }

Note that you also need to add the following permissions to your app's manifest file to use the biometric library:

<uses-permission android:name="android.permission.USE_BIOMETRIC"/> <uses-permission android:name="android.permission.USE_FINGERPRINT"/> <uses-permission android:name="android.permission.USE_FACE"/> <uses-permission android:name="android.permission.USE_IRIS"/>

Make sure to handle the case where the device does not support biometric authentication, or the user has not enrolled any biometric credentials on their device.

Read more about Biometric Library