Introduction
The androidx.biometric.BiometricPrompt class in Jetpack is a powerful tool for developers to use for authentication purposes. However, it has been reported that it can throw a NullPointerException when used in certain circumstances. This article will discuss the causes of this issue and provide solutions to help developers avoid this issue in the future. We will also discuss the best practices for using the BiometricPrompt class and how to handle the NullPointerException if it does occur.
Solution
The most likely cause of this issue is that the BiometricPrompt is not initialized correctly. To fix this, make sure that the BiometricPrompt is initialized with the correct parameters. Additionally, ensure that the BiometricPrompt is initialized with the correct context, such as the application context. Finally, make sure that the BiometricPrompt is initialized with the correct executor, such as the main thread executor.
This was reported three months ago as a bug, and it was reported as fixed two months ago. However, they have not yet released a fresh artifact.
There are some comments in that issue that suggest that “it’s a timing thing”, and that adding delays can help as a workaround.
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solved Jetpack’s BiometricPrompt (androidx.biometric.BiometricPrompt) throws NullPointerException
Solving Jetpack’s BiometricPrompt (androidx.biometric.BiometricPrompt) NullPointerException
If you’re using Jetpack’s BiometricPrompt (androidx.biometric.BiometricPrompt) and you’re getting a NullPointerException, you’re not alone. This is a common issue that many Android developers have encountered. Fortunately, there are a few simple steps you can take to solve this problem.
Step 1: Check Your Manifest
The first step is to check your AndroidManifest.xml file and make sure that you have the necessary permissions set up. Specifically, you need to add the following permissions:
- android.permission.USE_BIOMETRIC
- android.permission.USE_FINGERPRINT
If you don’t have these permissions set up, the BiometricPrompt will throw a NullPointerException.
Step 2: Check Your BiometricPrompt Instance
The next step is to check your BiometricPrompt instance. Make sure that you are passing in the correct parameters when you create the instance. Specifically, you need to make sure that you are passing in a valid BiometricPrompt.AuthenticationCallback instance. If you don’t, the BiometricPrompt will throw a NullPointerException.
Step 3: Check Your BiometricPrompt Callback
The last step is to check your BiometricPrompt.AuthenticationCallback instance. Make sure that you are implementing the onAuthenticationError and onAuthenticationSucceeded methods. If you don’t, the BiometricPrompt will throw a NullPointerException.
By following these steps, you should be able to solve the NullPointerException issue with Jetpack’s BiometricPrompt (androidx.biometric.BiometricPrompt). If you’re still having issues, you can reach out to the Android developer community for help.