Add the next button navigation view to a default long scroll

datacapture/src/main/java/com/google/android/fhir/datacapture/QuestionnaireAdapterItem.kt

@@ -34,4 +34,7 @@ internal sealed interface QuestionnaireAdapterItem {
     val responses: List<QuestionnaireResponse.QuestionnaireResponseItemComponent>,
     val title: String,
   ) : QuestionnaireAdapterItem
+
+  data class Navigation(val questionnaireNavigationUIState: QuestionnaireNavigationUIState) :
+    QuestionnaireAdapterItem
 }

datacapture/src/main/java/com/google/android/fhir/datacapture/QuestionnaireEditAdapter.kt

@@ -24,6 +24,7 @@ import androidx.recyclerview.widget.RecyclerView
 import com.google.android.fhir.datacapture.contrib.views.PhoneNumberViewHolderFactory
 import com.google.android.fhir.datacapture.extensions.inflate
 import com.google.android.fhir.datacapture.extensions.itemControl
+import com.google.android.fhir.datacapture.views.NavigationViewHolder
 import com.google.android.fhir.datacapture.views.QuestionnaireViewItem
 import com.google.android.fhir.datacapture.views.factories.AttachmentViewHolderFactory
 import com.google.android.fhir.datacapture.views.factories.AutoCompleteViewHolderFactory
@@ -69,6 +70,13 @@ internal class QuestionnaireEditAdapter(
           ),
         )
       }
+      ViewType.Type.NAVIGATION -> {
+        ViewHolder.NavigationHolder(
+          NavigationViewHolder(
+            parent.inflate(R.layout.pagination_navigation_view),
+          ),
+        )
+      }
     }
   }
 
@@ -122,6 +130,10 @@ internal class QuestionnaireEditAdapter(
         holder as ViewHolder.RepeatedGroupHeaderHolder
         holder.viewHolder.bind(item)
       }
+      is QuestionnaireAdapterItem.Navigation -> {
+        holder as ViewHolder.NavigationHolder
+        holder.viewHolder.bind(item.questionnaireNavigationUIState)
+      }
     }
   }
 
@@ -143,6 +155,10 @@ internal class QuestionnaireEditAdapter(
         // All of the repeated group headers will be rendered identically
         subtype = 0
       }
+      is QuestionnaireAdapterItem.Navigation -> {
+        type = ViewType.Type.NAVIGATION
+        subtype = 0xFFFFFF
+      }
     }
     return ViewType.from(type = type, subtype = subtype).viewType
   }
@@ -174,6 +190,7 @@ internal class QuestionnaireEditAdapter(
     enum class Type {
       QUESTION,
       REPEATED_GROUP_HEADER,
+      NAVIGATION,
     }
   }
 
@@ -269,6 +286,8 @@ internal class QuestionnaireEditAdapter(
 
     class RepeatedGroupHeaderHolder(val viewHolder: RepeatedGroupHeaderItemViewHolder) :
       ViewHolder(viewHolder.itemView)
+
+    class NavigationHolder(val viewHolder: NavigationViewHolder) : ViewHolder(viewHolder.itemView)
   }
 
   internal companion object {
@@ -296,6 +315,7 @@ internal object DiffCallbacks {
             newItem is QuestionnaireAdapterItem.RepeatedGroupHeader &&
               oldItem.index == newItem.index
           }
+          is QuestionnaireAdapterItem.Navigation -> newItem is QuestionnaireAdapterItem.Navigation
         }
 
       override fun areContentsTheSame(
@@ -311,6 +331,10 @@ internal object DiffCallbacks {
             newItem is QuestionnaireAdapterItem.RepeatedGroupHeader &&
               oldItem.responses == newItem.responses
           }
+          is QuestionnaireAdapterItem.Navigation -> {
+            newItem is QuestionnaireAdapterItem.Navigation &&
+              oldItem.questionnaireNavigationUIState == newItem.questionnaireNavigationUIState
+          }
         }
     }
 

datacapture/src/main/java/com/google/android/fhir/datacapture/QuestionnaireFragment.kt

@@ -21,7 +21,6 @@ import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
-import android.widget.Button
 import androidx.annotation.VisibleForTesting
 import androidx.appcompat.view.ContextThemeWrapper
 import androidx.core.content.res.use
@@ -34,6 +33,7 @@ import androidx.lifecycle.lifecycleScope
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
 import com.google.android.fhir.datacapture.validation.Invalid
+import com.google.android.fhir.datacapture.views.NavigationViewHolder
 import com.google.android.fhir.datacapture.views.factories.QuestionnaireItemViewHolderFactory
 import com.google.android.material.progressindicator.LinearProgressIndicator
 import kotlinx.coroutines.launch
@@ -94,58 +94,44 @@ class QuestionnaireFragment : Fragment() {
       view.findViewById<RecyclerView>(R.id.questionnaire_edit_recycler_view)
     val questionnaireReviewRecyclerView =
       view.findViewById<RecyclerView>(R.id.questionnaire_review_recycler_view)
-    val paginationPreviousButton = view.findViewById<View>(R.id.pagination_previous_button)
-    paginationPreviousButton.setOnClickListener { viewModel.goToPreviousPage() }
-    val paginationNextButton = view.findViewById<View>(R.id.pagination_next_button)
-    paginationNextButton.setOnClickListener { viewModel.goToNextPage() }
-    view.findViewById<Button>(R.id.cancel_questionnaire).setOnClickListener {
+
+    // This container frame floats at the bottom of the view to make navigation controls visible at
+    // all times when the user scrolls. Use
+    // [QuestionnaireFragment.Builder.setShowNavigationInDefaultLongScroll] to disable this.
+    val bottomNavContainerFrame = view.findViewById<View>(R.id.bottom_nav_container_frame)
+
+    viewModel.setOnCancelButtonClickListener {
       QuestionnaireCancelDialogFragment()
         .show(requireActivity().supportFragmentManager, QuestionnaireCancelDialogFragment.TAG)
     }
-
-    view
-      .findViewById<Button>(R.id.submit_questionnaire)
-      .apply {
-        text =
-          requireArguments()
-            .getString(EXTRA_SUBMIT_BUTTON_TEXT, getString(R.string.submit_questionnaire))
-      }
-      .setOnClickListener {
-        lifecycleScope.launch {
-          viewModel.validateQuestionnaireAndUpdateUI().let { validationMap ->
-            if (validationMap.values.flatten().filterIsInstance<Invalid>().isEmpty()) {
-              setFragmentResult(SUBMIT_REQUEST_KEY, Bundle.EMPTY)
-            } else {
-              val errorViewModel: QuestionnaireValidationErrorViewModel by activityViewModels()
-              errorViewModel.setQuestionnaireAndValidation(viewModel.questionnaire, validationMap)
-              QuestionnaireValidationErrorMessageDialogFragment()
-                .show(
-                  requireActivity().supportFragmentManager,
-                  QuestionnaireValidationErrorMessageDialogFragment.TAG,
-                )
-            }
+    viewModel.setOnSubmitButtonClickListener {
+      lifecycleScope.launch {
+        viewModel.validateQuestionnaireAndUpdateUI().let { validationMap ->
+          if (validationMap.values.flatten().filterIsInstance<Invalid>().isEmpty()) {
+            setFragmentResult(SUBMIT_REQUEST_KEY, Bundle.EMPTY)
+          } else {
+            val errorViewModel: QuestionnaireValidationErrorViewModel by activityViewModels()
+            errorViewModel.setQuestionnaireAndValidation(viewModel.questionnaire, validationMap)
+            QuestionnaireValidationErrorMessageDialogFragment()
+              .show(
+                requireActivity().supportFragmentManager,
+                QuestionnaireValidationErrorMessageDialogFragment.TAG,
+              )
           }
         }
       }
+    }
     val questionnaireProgressIndicator: LinearProgressIndicator =
       view.findViewById(R.id.questionnaire_progress_indicator)
     val questionnaireEditAdapter =
       QuestionnaireEditAdapter(questionnaireItemViewHolderFactoryMatchersProvider.get())
     val questionnaireReviewAdapter = QuestionnaireReviewAdapter()
 
-    val submitButton = requireView().findViewById<Button>(R.id.submit_questionnaire)
-    val cancelButton = requireView().findViewById<Button>(R.id.cancel_questionnaire)
-
     val reviewModeEditButton =
       view.findViewById<View>(R.id.review_mode_edit_button).apply {
         setOnClickListener { viewModel.setReviewMode(false) }
       }
 
-    val reviewModeButton =
-      view.findViewById<View>(R.id.review_mode_button).apply {
-        setOnClickListener { viewModel.setReviewMode(true) }
-      }
-
     questionnaireEditRecyclerView.adapter = questionnaireEditAdapter
     val linearLayoutManager = LinearLayoutManager(view.context)
     questionnaireEditRecyclerView.layoutManager = linearLayoutManager
@@ -163,23 +149,20 @@ class QuestionnaireFragment : Fragment() {
             // Set items
             questionnaireEditRecyclerView.visibility = View.GONE
             questionnaireReviewAdapter.submitList(
-              state.items.filterIsInstance<QuestionnaireAdapterItem.Question>(),
+              state.items,
             )
             questionnaireReviewRecyclerView.visibility = View.VISIBLE
-
-            // Set button visibility
-            submitButton.visibility = if (displayMode.showSubmitButton) View.VISIBLE else View.GONE
-            cancelButton.visibility = if (displayMode.showCancelButton) View.VISIBLE else View.GONE
-
-            reviewModeButton.visibility = View.GONE
             reviewModeEditButton.visibility =
               if (displayMode.showEditButton) {
                 View.VISIBLE
               } else {
                 View.GONE
               }
-            paginationPreviousButton.visibility = View.GONE
-            paginationNextButton.visibility = View.GONE
+
+            // Set bottom navigation
+            bottomNavContainerFrame.visibility = View.VISIBLE
+            NavigationViewHolder(bottomNavContainerFrame)
+              .bind(state.bottomNavItems.single().questionnaireNavigationUIState)
 
             // Hide progress indicator
             questionnaireProgressIndicator.visibility = View.GONE
@@ -189,25 +172,12 @@ class QuestionnaireFragment : Fragment() {
             questionnaireReviewRecyclerView.visibility = View.GONE
             questionnaireEditAdapter.submitList(state.items)
             questionnaireEditRecyclerView.visibility = View.VISIBLE
-
-            // Set button visibility
-            submitButton.visibility =
-              if (displayMode.pagination.showSubmitButton) View.VISIBLE else View.GONE
-            cancelButton.visibility =
-              if (displayMode.pagination.showCancelButton) View.VISIBLE else View.GONE
-            reviewModeButton.visibility =
-              if (displayMode.pagination.showReviewButton) View.VISIBLE else View.GONE
             reviewModeEditButton.visibility = View.GONE
 
-            if (displayMode.pagination.isPaginated) {
-              paginationPreviousButton.visibility =
-                if (displayMode.pagination.hasPreviousPage) View.VISIBLE else View.GONE
-              paginationNextButton.visibility =
-                if (displayMode.pagination.hasNextPage) View.VISIBLE else View.GONE
-            } else {
-              paginationPreviousButton.visibility = View.GONE
-              paginationNextButton.visibility = View.GONE
-            }
+            // Set bottom navigation
+            bottomNavContainerFrame.visibility = View.VISIBLE
+            NavigationViewHolder(bottomNavContainerFrame)
+              .bind(state.bottomNavItems.single().questionnaireNavigationUIState)
 
             // Set progress indicator
             questionnaireProgressIndicator.visibility = View.VISIBLE
@@ -241,13 +211,9 @@ class QuestionnaireFragment : Fragment() {
           is DisplayMode.InitMode -> {
             questionnaireReviewRecyclerView.visibility = View.GONE
             questionnaireEditRecyclerView.visibility = View.GONE
-            paginationPreviousButton.visibility = View.GONE
-            paginationNextButton.visibility = View.GONE
             questionnaireProgressIndicator.visibility = View.GONE
-            submitButton.visibility = View.GONE
-            cancelButton.visibility = View.GONE
-            reviewModeButton.visibility = View.GONE
             reviewModeEditButton.visibility = View.GONE
+            bottomNavContainerFrame.visibility = View.GONE
           }
         }
       }
@@ -425,6 +391,14 @@ class QuestionnaireFragment : Fragment() {
      */
     fun setShowCancelButton(value: Boolean) = apply { args.add(EXTRA_SHOW_CANCEL_BUTTON to value) }
 
+    /**
+     * A [Boolean] extra to show questionnaire page as a default/long scroll with the
+     * previous/next/submit buttons anchored to bottom/end of page. Default is false.
+     */
+    fun setShowNavigationInDefaultLongScroll(value: Boolean) = apply {
+      args.add(EXTRA_SHOW_NAVIGATION_IN_DEFAULT_LONG_SCROLL to value)
+    }
+
     @VisibleForTesting fun buildArgs() = bundleOf(*args.toTypedArray())
 
     /** @return A [QuestionnaireFragment] with provided [Bundle] arguments. */
@@ -524,6 +498,9 @@ class QuestionnaireFragment : Fragment() {
 
     internal const val EXTRA_SUBMIT_BUTTON_TEXT = "submit-button-text"
 
+    internal const val EXTRA_SHOW_NAVIGATION_IN_DEFAULT_LONG_SCROLL =
+      "show-navigation-in-default-long-scroll"
+
     fun builder() = Builder()
   }
 

datacapture/src/main/java/com/google/android/fhir/datacapture/QuestionnaireNavigationViewUIState.kt

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2023-2024 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.android.fhir.datacapture
+
+sealed class QuestionnaireNavigationViewUIState(val isShown: Boolean, val isEnabled: Boolean) {
+  data object Hidden : QuestionnaireNavigationViewUIState(isShown = false, isEnabled = false)
+
+  data class Enabled(val labelText: String? = null, val onClickAction: () -> Unit) :
+    QuestionnaireNavigationViewUIState(isShown = true, isEnabled = true)
+}
+
+data class QuestionnaireNavigationUIState(
+  val navPrevious: QuestionnaireNavigationViewUIState = QuestionnaireNavigationViewUIState.Hidden,
+  val navNext: QuestionnaireNavigationViewUIState = QuestionnaireNavigationViewUIState.Hidden,
+  val navSubmit: QuestionnaireNavigationViewUIState = QuestionnaireNavigationViewUIState.Hidden,
+  val navCancel: QuestionnaireNavigationViewUIState = QuestionnaireNavigationViewUIState.Hidden,
+  val navReview: QuestionnaireNavigationViewUIState = QuestionnaireNavigationViewUIState.Hidden,
+)

datacapture/src/main/java/com/google/android/fhir/datacapture/QuestionnaireReviewAdapter.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2023 Google LLC
+ * Copyright 2022-2024 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,21 +16,65 @@
 
 package com.google.android.fhir.datacapture
 
+import android.view.LayoutInflater
 import android.view.ViewGroup
 import androidx.recyclerview.widget.ListAdapter
+import androidx.recyclerview.widget.RecyclerView
+import com.google.android.fhir.datacapture.views.NavigationViewHolder
 import com.google.android.fhir.datacapture.views.factories.QuestionnaireItemViewHolder
 import com.google.android.fhir.datacapture.views.factories.ReviewViewHolderFactory
 
 /** List Adapter used to bind answers to [QuestionnaireItemViewHolder] in review mode. */
 internal class QuestionnaireReviewAdapter :
-  ListAdapter<QuestionnaireAdapterItem.Question, QuestionnaireItemViewHolder>(
-    DiffCallbacks.QUESTIONS,
+  ListAdapter<QuestionnaireAdapterItem, RecyclerView.ViewHolder>(
+    DiffCallbacks.ITEMS,
   ) {
-  override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): QuestionnaireItemViewHolder {
-    return ReviewViewHolderFactory.create(parent)
+  override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
+    val typedViewType = QuestionnaireEditAdapter.ViewType.parse(viewType)
+    return when (typedViewType.type) {
+      QuestionnaireEditAdapter.ViewType.Type.QUESTION -> ReviewViewHolderFactory.create(parent)
+      QuestionnaireEditAdapter.ViewType.Type.NAVIGATION ->
+        NavigationViewHolder(
+          LayoutInflater.from(parent.context)
+            .inflate(R.layout.pagination_navigation_view, parent, false),
+        )
+      QuestionnaireEditAdapter.ViewType.Type.REPEATED_GROUP_HEADER -> TODO()
+    }
   }
 
-  override fun onBindViewHolder(holder: QuestionnaireItemViewHolder, position: Int) {
-    holder.bind(getItem(position).item)
+  override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
+    when (val item = getItem(position)) {
+      is QuestionnaireAdapterItem.Question -> {
+        holder as QuestionnaireItemViewHolder
+        holder.bind(item.item)
+      }
+      is QuestionnaireAdapterItem.Navigation -> {
+        holder as NavigationViewHolder
+        holder.bind(item.questionnaireNavigationUIState)
+      }
+      is QuestionnaireAdapterItem.RepeatedGroupHeader -> TODO()
+    }
+  }
+
+  override fun getItemViewType(position: Int): Int {
+    // Because we have multiple Item subtypes, we will pack two ints into the item view type.
+
+    // The first 8 bits will be represented by this type, which is unique for each Item subclass.
+    val type: QuestionnaireEditAdapter.ViewType.Type
+    // The last 24 bits will be represented by this subtype, which will further divide each Item
+    // subclass into more view types.
+    val subtype: Int
+    when (getItem(position)) {
+      is QuestionnaireAdapterItem.Question -> {
+        type = QuestionnaireEditAdapter.ViewType.Type.QUESTION
+        subtype = 0xFFFFFF
+      }
+      is QuestionnaireAdapterItem.Navigation -> {
+        type = QuestionnaireEditAdapter.ViewType.Type.NAVIGATION
+        subtype = 0xFFFFFF
+      }
+      is QuestionnaireAdapterItem.RepeatedGroupHeader -> TODO()
+    }
+    return QuestionnaireEditAdapter.ViewType.from(type = type, subtype = subtype).viewType
   }
 }