Android crashed after updating androidx biometric to 1.0.0-alpha04

Question

Everything works fine with 'androidx.biometric:biometric:1.0.0-alpha03', however when I build my project with the latest 'androidx.biometric:biometric:1.0.0-alpha04' and call myBiometricPrompt.authenticate(promptInfo) it throws this exception: FragmentManager is already executing transactions.

Here is the stacktrace:

 java.lang.IllegalStateException: FragmentManager is already executing transactions
        at androidx.fragment.app.FragmentManagerImpl.ensureExecReady(FragmentManager.java:2207)
        at androidx.fragment.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2267)
        at androidx.fragment.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:814)
        at androidx.biometric.BiometricPrompt.authenticateInternal(BiometricPrompt.java:525)
        at androidx.biometric.BiometricPrompt.authenticate(BiometricPrompt.java:465)
        at com.my.app.ui.LoginFragment.handleTouchIdAuth(LoginFragment.kt:161)
        at com.my.app.ui.LoginFragment.onViewCreated(LoginFragment.kt:62)
        at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1471)
        at androidx.fragment.app.FragmentManagerImpl.addAddedFragments(FragmentManager.java:2646)
        at androidx.fragment.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2416)
        at androidx.fragment.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2372)
        at androidx.fragment.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:2273)
        at androidx.fragment.app.FragmentManagerImpl.dispatchStateChange(FragmentManager.java:3273)
        at androidx.fragment.app.FragmentManagerImpl.dispatchActivityCreated(FragmentManager.java:3229)
        at androidx.fragment.app.Fragment.performActivityCreated(Fragment.java:2466)
        at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1483)
        at androidx.fragment.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1784)
        at androidx.fragment.app.FragmentManagerImpl.moveToState(FragmentManager.java:1852)
        at androidx.fragment.app.FragmentManagerImpl.dispatchStateChange(FragmentManager.java:3269)
        at androidx.fragment.app.FragmentManagerImpl.dispatchActivityCreated(FragmentManager.java:3229)
        at androidx.fragment.app.FragmentController.dispatchActivityCreated(FragmentController.java:201)
        at androidx.fragment.app.FragmentActivity.onStart(FragmentActivity.java:620)
        at androidx.appcompat.app.AppCompatActivity.onStart(AppCompatActivity.java:178)
        at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1391)
        at android.app.Activity.performStart(Activity.java:7157)
        at android.app.ActivityThread.handleStartActivity(ActivityThread.java:2937)
        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:180)
        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:165)
        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:142)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:70)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1808)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:193)
        at android.app.ActivityThread.main(ActivityThread.java:6669)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

Does anyone know what happened and what to do? For now, I'll stick with version 1.0.0-alpha03

Thank you!

Answer 1

The problem is fixed in androidx.biometric:biometric:1.0.0-beta01 by providing a second constructor. Until this release, i solved the issue by reverting to alpha03 but there's an actual solution available now.

You can find the beta01 release notes here

We’ve introduced a second constructor for BiometricPrompt that allows it to be hosted in a Fragment (as opposed to the existing constructor, which requires a FragmentActivity).

You can find the new BiometricPrompt constructor documentation here

BiometricPrompt(Fragment fragment, Executor executor, BiometricPrompt.AuthenticationCallback callback)

To fix, please follow the simple steps:

1. Change your build.gradle to use biometric version 1.0.0-beta01

2. Use the new constructor. In short, change the first argument to your fragment instead of the activity. See my code change below:

   val biometricPrompt = BiometricPrompt(activity!!, executor, callback)
   // Change the above line to the below line
   val biometricPrompt = BiometricPrompt(this, executor, callback)