seletion state retain support in question player

app/src/main/java/org/oppia/android/app/player/state/StateFragment.kt

@@ -43,8 +43,8 @@ class StateFragment :
     /** Arguments key for StateFragment. */
     const val STATE_FRAGMENT_ARGUMENTS_KEY = "StateFragment.arguments"
 
-    /** Arguments key for StateFragment. */
-    const val STATE_FRAGMENT_USER_ANSWER_STATE_KEY = "StateFragment.user_answer_state"
+    /** Arguments key for StateFragment saved state. */
+    const val STATE_FRAGMENT_STATE_KEY = "StateFragment.state"
 
     /**
      * Creates a new instance of a StateFragment.
@@ -92,7 +92,7 @@ class StateFragment :
       arguments?.getProto(STATE_FRAGMENT_ARGUMENTS_KEY, StateFragmentArguments.getDefaultInstance())
 
     val userAnswerState = savedInstanceState?.getProto(
-      STATE_FRAGMENT_USER_ANSWER_STATE_KEY,
+      STATE_FRAGMENT_STATE_KEY,
       UserAnswerState.getDefaultInstance()
     ) ?: UserAnswerState.getDefaultInstance()
 
@@ -161,7 +161,7 @@ class StateFragment :
   override fun onSaveInstanceState(outState: Bundle) {
     super.onSaveInstanceState(outState)
     outState.putProto(
-      STATE_FRAGMENT_USER_ANSWER_STATE_KEY,
+      STATE_FRAGMENT_STATE_KEY,
       stateFragmentPresenter.getUserAnswerState()
     )
   }

app/src/main/java/org/oppia/android/app/topic/questionplayer/QuestionPlayerFragment.kt

@@ -22,6 +22,8 @@ import org.oppia.android.app.player.state.listener.SubmitNavigationButtonListene
 import org.oppia.android.util.extensions.getProto
 import org.oppia.android.util.extensions.putProto
 import javax.inject.Inject
+import org.oppia.android.app.model.UserAnswerState
+import org.oppia.android.app.player.state.StateFragment
 
 /** Fragment that contains all questions in Question Player. */
 class QuestionPlayerFragment :
@@ -52,8 +54,12 @@ class QuestionPlayerFragment :
     val args = checkNotNull(arguments) {
       "Expected arguments to be passed to QuestionPlayerFragment"
     }
+    val userAnswerState = savedInstanceState?.getProto(
+      QUESTION_PLAYER_FRAGMENT_STATE_KEY,
+      UserAnswerState.getDefaultInstance()
+    ) ?: UserAnswerState.getDefaultInstance()
     val profileId = args.getProto(PROFILE_ID_ARGUMENT_KEY, ProfileId.getDefaultInstance())
-    return questionPlayerFragmentPresenter.handleCreateView(inflater, container, profileId)
+    return questionPlayerFragmentPresenter.handleCreateView(inflater, container, profileId,userAnswerState)
   }
 
   override fun onAnswerReadyForSubmission(answer: UserAnswer) {
@@ -98,6 +104,9 @@ class QuestionPlayerFragment :
   companion object {
     private const val PROFILE_ID_ARGUMENT_KEY = "QuestionPlayerFragment.profile_id"
 
+    /** Arguments key for QuestionPlayerFragment saved state. */
+    const val QUESTION_PLAYER_FRAGMENT_STATE_KEY = "QuestionPlayerFragment.state"
+
     /**
      * Creates a new fragment to play a question session.
      *
@@ -112,4 +121,12 @@ class QuestionPlayerFragment :
       }
     }
   }
+
+  override fun onSaveInstanceState(outState: Bundle) {
+    super.onSaveInstanceState(outState)
+    outState.putProto(
+      QUESTION_PLAYER_FRAGMENT_STATE_KEY,
+      questionPlayerFragmentPresenter.getUserAnswerState()
+    )
+  }
 }

app/src/main/java/org/oppia/android/app/topic/questionplayer/QuestionPlayerFragmentPresenter.kt

@@ -36,6 +36,7 @@ import org.oppia.android.util.data.DataProvider
 import org.oppia.android.util.data.DataProviders.Companion.toLiveData
 import org.oppia.android.util.gcsresource.QuestionResourceBucketName
 import javax.inject.Inject
+import org.oppia.android.app.model.UserAnswerState
 
 /** The presenter for [QuestionPlayerFragment]. */
 @FragmentScope
@@ -69,7 +70,8 @@ class QuestionPlayerFragmentPresenter @Inject constructor(
   fun handleCreateView(
     inflater: LayoutInflater,
     container: ViewGroup?,
-    profileId: ProfileId
+    profileId: ProfileId,
+    userAnswerState: UserAnswerState
   ): View? {
     binding = QuestionPlayerFragmentBinding.inflate(
       inflater,
@@ -79,7 +81,7 @@ class QuestionPlayerFragmentPresenter @Inject constructor(
     this.profileId = profileId
 
     recyclerViewAssembler = createRecyclerViewAssembler(
-      assemblerBuilderFactory.create(resourceBucketName, "skill", profileId),
+      assemblerBuilderFactory.create(resourceBucketName, "skill", profileId,userAnswerState),
       binding.congratulationsTextView,
       binding.congratulationsTextConfettiView
     )
@@ -154,6 +156,11 @@ class QuestionPlayerFragmentPresenter @Inject constructor(
     recyclerViewAssembler.adapter.notifyDataSetChanged()
   }
 
+  /** Returns the [UserAnswerState] representing the user's current pending answer. */
+  fun getUserAnswerState(): UserAnswerState {
+    return questionViewModel.getUserAnswerState(recyclerViewAssembler::getPendingAnswerHandler)
+  }
+
   /**
    * Updates whether the submit button should be active based on whether the pending answer is in an
    * error state.
@@ -257,6 +264,9 @@ class QuestionPlayerFragmentPresenter @Inject constructor(
   private fun subscribeToAnswerOutcome(
     answerOutcomeResultLiveData: LiveData<AsyncResult<AnsweredQuestionOutcome>>
   ) {
+    if (questionViewModel.getCanSubmitAnswer().get() == true) {
+      recyclerViewAssembler.resetUserAnswerState()
+    }
     val answerOutcomeLiveData =
       Transformations.map(answerOutcomeResultLiveData, ::processAnsweredQuestionOutcome)
     answerOutcomeLiveData.observe(

app/src/main/java/org/oppia/android/app/topic/questionplayer/QuestionPlayerViewModel.kt

@@ -12,6 +12,7 @@ import org.oppia.android.app.translation.AppLanguageResourceHandler
 import org.oppia.android.app.viewmodel.ObservableArrayList
 import org.oppia.android.app.viewmodel.ObservableViewModel
 import javax.inject.Inject
+import org.oppia.android.app.model.UserAnswerState
 
 /** [ObservableViewModel] for the question player. */
 class QuestionPlayerViewModel @Inject constructor(
@@ -92,6 +93,13 @@ class QuestionPlayerViewModel @Inject constructor(
     }
   }
 
+  fun getUserAnswerState(
+    retrieveAnswerHandler: (List<StateItemViewModel>) -> InteractionAnswerHandler?
+  ): UserAnswerState {
+    return retrieveAnswerHandler(getAnswerItemList())?.getUserAnswerState()
+      ?: UserAnswerState.getDefaultInstance()
+  }
+
   private fun getPendingAnswerWithoutError(
     answerHandler: InteractionAnswerHandler?
   ): UserAnswer? {

app/src/main/res/layout/item_selection_interaction_items.xml

@@ -27,14 +27,13 @@
       android:id="@+id/item_selection_checkbox"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
+      app:buttonTint="@{viewModel.isEnabled ? @color/component_color_shared_item_selection_interaction_enabled_color : @color/component_color_shared_item_selection_interaction_disabled_color}"
       android:clickable="false"
       android:enabled="@{viewModel.isEnabled}"
       android:focusable="false"
       android:labelFor="@id/item_selection_contents_text_view"
-      app:buttonTint="@{viewModel.isEnabled ? @color/component_color_shared_item_selection_interaction_enabled_color : @color/component_color_shared_item_selection_interaction_disabled_color}"
       android:checked="@{viewModel.answerSelected}"
       />
-
     <TextView
       android:id="@+id/item_selection_contents_text_view"
       android:layout_width="wrap_content"