IssueTracker

Component used: Navigation Version used: 2.4.0-alpha02 Devices/Android versions reproduced on: Pixel 4a

Unfortunately I do not have repro steps as this is showing on the developer console after updating to Navigation 2.4.0-alpha02. It appears there is an exception when a Dialog (declared in the nav graph) is closed. The stack trace is below

java.util.NoSuchElementException: 
  at androidx.navigation.fragment.DialogFragmentNavigator$observer$1.onStateChanged (DialogFragmentNavigator.java:87)
  at androidx.lifecycle.LifecycleRegistry$ObserverWithState.dispatchEvent (LifecycleRegistry.java:14)
  at androidx.lifecycle.LifecycleRegistry.backwardPass (LifecycleRegistry.java:69)
  at androidx.lifecycle.LifecycleRegistry.sync (LifecycleRegistry.java:41)
  at androidx.lifecycle.LifecycleRegistry.moveToState (LifecycleRegistry.java:19)
  at androidx.lifecycle.LifecycleRegistry.handleLifecycleEvent (LifecycleRegistry.java:9)
  at androidx.fragment.app.Fragment.performStop (Fragment.java:20)
  at androidx.fragment.app.FragmentStateManager.stop (FragmentStateManager.java:33)
  at androidx.fragment.app.FragmentStateManager.moveToExpectedState (FragmentStateManager.java:142)
  at androidx.fragment.app.FragmentManager.executeOpsTogether (FragmentManager.java:230)
  at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute (FragmentManager.java:81)
  at androidx.fragment.app.FragmentManager.execPendingActions (FragmentManager.java:21)
  at androidx.fragment.app.FragmentManager$4.run (FragmentManager.java:3)
  at android.os.Handler.handleCallback (Handler.java:938)
  at android.os.Handler.dispatchMessage (Handler.java:99)
  at android.os.Looper.loop (Looper.java:223)
  at android.app.ActivityThread.main (ActivityThread.java:7664)
  at java.lang.reflect.Method.invoke (Native Method)
  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:592)
  at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:947)

This is how the nav graph is defined

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/nav_graph"
    app:startDestination="@id/dataListFragment">

    <fragment
        android:id="@+id/dataListFragment"
        android:name="com.example.myapp.feature.list.DataListFragment"
        android:label="@string/app_name">
        <action
            android:id="@+id/action_dataListFragment_to_displayEntryFragment"
            app:destination="@id/displayEntryFragment"
            app:enterAnim="@anim/fragment_enter_from_right"
            app:exitAnim="@anim/fragment_exit_to_left"
            app:popEnterAnim="@anim/fragment_enter_from_left"
            app:popExitAnim="@anim/fragment_exit_to_right" />
        <action
            android:id="@+id/action_dataListFragment_to_editEntryFragment"
            app:destination="@id/editEntryFragment"
            app:enterAnim="@anim/fragment_enter_from_right"
            app:exitAnim="@anim/fragment_exit_to_left"
            app:popEnterAnim="@anim/fragment_enter_from_left"
            app:popExitAnim="@anim/fragment_exit_to_right" />
        <action
            android:id="@+id/action_dataListFragment_to_settingsFragment"
            app:destination="@id/settingsFragment"
            app:enterAnim="@anim/fragment_enter_from_right"
            app:exitAnim="@anim/fragment_exit_to_left"
            app:popEnterAnim="@anim/fragment_enter_from_left"
            app:popExitAnim="@anim/fragment_exit_to_right" />
        <action
            android:id="@+id/action_dataListFragment_to_pinFragment"
            app:destination="@id/pinFragment"
            app:enterAnim="@anim/fade_in"
            app:exitAnim="@anim/fade_out"
            app:popEnterAnim="@anim/fade_in"
            app:popExitAnim="@anim/fade_out" />
        <action
            android:id="@+id/action_dataListFragment_to_onboardingFragment"
            app:destination="@id/onboardingFragment"
            app:enterAnim="@anim/fade_in"
            app:exitAnim="@anim/fade_out"
            app:popEnterAnim="@anim/fade_in"
            app:popExitAnim="@anim/fade_out" />
        <action
            android:id="@+id/action_dataListFragment_to_analysisFragment"
            app:destination="@id/analysisFragment"
            app:enterAnim="@anim/fragment_enter_from_right"
            app:exitAnim="@anim/fragment_exit_to_left"
            app:popEnterAnim="@anim/fragment_enter_from_left"
            app:popExitAnim="@anim/fragment_exit_to_right"/>
        <action
            android:id="@+id/action_dataListFragment_to_aboutDialogFragment"
            app:destination="@id/aboutDialogFragment" />
        <action
            android:id="@+id/action_dataListFragment_to_driveInfoDialogFragment"
            app:destination="@id/driveInfoDialogFragment" />
        <action
            android:id="@+id/action_dataListFragment_to_passwordGeneratorDialogFragment"
            app:destination="@id/passwordGeneratorDialogFragment" />
        <action
            android:id="@+id/action_dataListFragment_to_categoryPickerDialogFragment"
            app:destination="@id/categoryPickerDialogFragment" />
        <action
            android:id="@+id/action_dataListFragment_to_licensesDialogFragment"
            app:destination="@id/licensesDialogFragment" />
    </fragment>
    <fragment
        android:id="@+id/displayEntryFragment"
        android:name="com.example.myapp.feature.display.DisplayEntryFragment">
        <action
            android:id="@+id/action_displayEntryFragment_to_editEntryFragment"
            app:destination="@id/editEntryFragment"
            app:enterAnim="@anim/fragment_enter_from_right"
            app:exitAnim="@anim/fragment_exit_to_left"
            app:popEnterAnim="@anim/fragment_enter_from_left"
            app:popExitAnim="@anim/fragment_exit_to_right" />
        <action
            android:id="@+id/action_displayEntryFragment_to_pinFragment"
            app:destination="@id/pinFragment"
            app:enterAnim="@anim/fade_in"
            app:exitAnim="@anim/fade_out"
            app:popEnterAnim="@anim/fade_in"
            app:popExitAnim="@anim/fade_out" />
        <argument
            android:name="entryId"
            app:argType="integer" />
        <argument
            android:name="entryName"
            app:argType="string" />
    </fragment>
    <fragment
        android:id="@+id/editEntryFragment"
        android:name="com.example.myapp.feature.edit.EditEntryFragment"
        android:label="@string/title_add_entry">
        <action
            android:id="@+id/action_editEntryFragment_to_pinFragment"
            app:destination="@id/pinFragment"
            app:enterAnim="@anim/fade_in"
            app:exitAnim="@anim/fade_out"
            app:popEnterAnim="@anim/fade_in"
            app:popExitAnim="@anim/fade_out" />
        <argument
            android:name="dataEntry"
            android:defaultValue="@null"
            app:argType="com.example.myapp.repository.database.VaultEntry"
            app:nullable="true" />
        <argument
            android:name="entryId"
            app:argType="integer"
            android:defaultValue="-1" />
        <action
            android:id="@+id/action_editEntryFragment_to_passwordGeneratorDialogFragment"
            app:destination="@id/passwordGeneratorDialogFragment" />
        <action
            android:id="@+id/action_editEntryFragment_to_categoryPickerDialogFragment"
            app:destination="@id/categoryPickerDialogFragment" />
    </fragment>
    <fragment
        android:id="@+id/settingsFragment"
        android:name="com.example.myapp.feature.settings.SettingsFragment"
        android:label="@string/settings">
        <action
            android:id="@+id/action_settingsFragment_to_pinFragment"
            app:destination="@id/pinFragment"
            app:enterAnim="@anim/fade_in"
            app:exitAnim="@anim/fade_out"
            app:popEnterAnim="@anim/fade_in"
            app:popExitAnim="@anim/fade_out" />
    </fragment>
    <fragment
        android:id="@+id/onboardingFragment"
        android:name="com.example.myapp.feature.onboarding.OnboardingFragment"/>
    <fragment
        android:id="@+id/pinFragment"
        android:name="com.example.myapp.feature.pin.PinFragment"
        android:label="@string/app_name" />
    <fragment
        android:id="@+id/analysisFragment"
        android:name="com.example.myapp.feature.analysis.AnalysisFragment"
        android:label="@string/password_analysis" >
        <action
            android:id="@+id/action_analysisFragment_to_pinFragment"
            app:destination="@id/pinFragment" />
        <action
            android:id="@+id/action_analysisFragment_to_displayEntryFragment"
            app:destination="@id/displayEntryFragment"
            app:enterAnim="@anim/fragment_enter_from_right"
            app:exitAnim="@anim/fragment_exit_to_left"
            app:popEnterAnim="@anim/fragment_enter_from_left"
            app:popExitAnim="@anim/fragment_exit_to_right" />
    </fragment>
    <dialog
        android:id="@+id/aboutDialogFragment"
        android:name="com.example.myapp.feature.list.AboutDialogFragment"
        android:label="AboutDialogFragment" />
    <dialog
        android:id="@+id/driveInfoDialogFragment"
        android:name="com.example.myapp.feature.edit.DriveInfoDialogFragment"
        android:label="DriveInfoDialogFragment" />
    <dialog
        android:id="@+id/passwordGeneratorDialogFragment"
        android:name="com.example.myapp.feature.passwordgenerator.PasswordGeneratorDialogFragment"
        android:label="PasswordGeneratorDialogFragment" >
        <argument
            android:name="mode"
            app:argType="com.example.myapp.feature.passwordgenerator.PasswordMode" />
    </dialog>
    <dialog
        android:id="@+id/categoryPickerDialogFragment"
        android:name="com.example.myapp.feature.common.categorypicker.CategoryPickerDialogFragment"
        android:label="CategoryPickerDialogFragment" >
        <argument
            android:name="index"
            app:argType="integer" />
    </dialog>
    <dialog
        android:id="@+id/licensesDialogFragment"
        android:name="com.example.myapp.feature.list.LicensesDialogFragment"
        android:label="LicensesDialogFragment" />
</navigation>