Fixed: When selecting page items the changes are not reflecting in UI.

* Improved the clicking on page item.
* Fixed: Page items are not showing updating after deleting.
* Fixed: Switch was not disabling when selecting the page items.
* Added SearchView, navigationIcon, and menuItems to page fragment.

app/src/main/java/org/kiwix/kiwixmobile/language/LanguageFragment.kt

@@ -38,6 +38,7 @@ import org.kiwix.kiwixmobile.core.base.BaseActivity
 import org.kiwix.kiwixmobile.core.base.BaseFragment
 import org.kiwix.kiwixmobile.core.extensions.viewModel
 import org.kiwix.kiwixmobile.core.main.CoreMainActivity
+import org.kiwix.kiwixmobile.core.page.SEARCH_ICON_TESTING_TAG
 import org.kiwix.kiwixmobile.core.ui.components.NavigationIcon
 import org.kiwix.kiwixmobile.core.ui.models.ActionMenuItem
 import org.kiwix.kiwixmobile.core.ui.models.IconItem
@@ -46,7 +47,6 @@ import org.kiwix.kiwixmobile.language.viewmodel.Action
 import org.kiwix.kiwixmobile.language.viewmodel.LanguageViewModel
 import javax.inject.Inject
 
-const val SEARCH_ICON_TESTING_TAG = "search"
 const val SAVE_ICON_TESTING_TAG = "saveLanguages"
 const val SEARCH_FIELD_TESTING_TAG = "searchField"
 

app/src/main/res/navigation/kiwix_nav_graph.xml

@@ -94,13 +94,11 @@
   <fragment
     android:id="@+id/bookmarksFragment"
     android:name="org.kiwix.kiwixmobile.core.page.bookmark.BookmarksFragment"
-    android:label="BookmarksFragment"
-    tools:layout="@layout/fragment_page" />
+    android:label="BookmarksFragment" />
   <fragment
     android:id="@+id/notesFragment"
     android:name="org.kiwix.kiwixmobile.core.page.notes.NotesFragment"
-    android:label="NotesFragment"
-    tools:layout="@layout/fragment_page" />
+    android:label="NotesFragment" />
   <fragment
     android:id="@+id/introFragment"
     android:name="org.kiwix.kiwixmobile.intro.IntroFragment"
@@ -115,8 +113,7 @@
   <fragment
     android:id="@+id/historyFragment"
     android:name="org.kiwix.kiwixmobile.core.page.history.HistoryFragment"
-    android:label="HistoryFragment"
-    tools:layout="@layout/fragment_page" />
+    android:label="HistoryFragment" />
   <fragment
     android:id="@+id/languageFragment"
     android:name="org.kiwix.kiwixmobile.language.LanguageFragment"

core/src/main/java/org/kiwix/kiwixmobile/core/page/PageFragment.kt

@@ -24,13 +24,20 @@ import android.view.Menu
 import android.view.MenuInflater
 import android.view.MenuItem
 import android.view.View
-import android.view.View.GONE
-import android.view.View.VISIBLE
 import android.view.ViewGroup
 import androidx.appcompat.app.AppCompatActivity
 import androidx.appcompat.view.ActionMode
 import androidx.appcompat.widget.SearchView
 import androidx.appcompat.widget.Toolbar
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.runtime.MutableState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.referentialEqualityPolicy
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.platform.ComposeView
 import androidx.core.view.MenuHost
 import androidx.core.view.MenuProvider
@@ -44,7 +51,6 @@ import org.kiwix.kiwixmobile.core.R
 import org.kiwix.kiwixmobile.core.base.BaseFragment
 import org.kiwix.kiwixmobile.core.base.FragmentActivityExtensions
 import org.kiwix.kiwixmobile.core.databinding.FragmentPageBinding
-import org.kiwix.kiwixmobile.core.extensions.ActivityExtensions.isCustomApp
 import org.kiwix.kiwixmobile.core.extensions.closeKeyboard
 import org.kiwix.kiwixmobile.core.extensions.setToolTipWithContentDescription
 import org.kiwix.kiwixmobile.core.extensions.setUpSearchView
@@ -52,14 +58,21 @@ import org.kiwix.kiwixmobile.core.main.CoreMainActivity
 import org.kiwix.kiwixmobile.core.page.adapter.OnItemClickListener
 import org.kiwix.kiwixmobile.core.page.adapter.Page
 import org.kiwix.kiwixmobile.core.page.adapter.PageAdapter
+import org.kiwix.kiwixmobile.core.page.notes.viewmodel.NotesState
 import org.kiwix.kiwixmobile.core.page.viewmodel.Action
 import org.kiwix.kiwixmobile.core.page.viewmodel.PageState
 import org.kiwix.kiwixmobile.core.page.viewmodel.PageViewModel
+import org.kiwix.kiwixmobile.core.ui.components.NavigationIcon
+import org.kiwix.kiwixmobile.core.ui.models.ActionMenuItem
+import org.kiwix.kiwixmobile.core.ui.models.IconItem
 import org.kiwix.kiwixmobile.core.utils.SharedPreferenceUtil
 import org.kiwix.kiwixmobile.core.utils.SimpleRecyclerViewScrollListener
 import org.kiwix.kiwixmobile.core.utils.SimpleTextListener
 import javax.inject.Inject
 
+const val SEARCH_ICON_TESTING_TAG = "search"
+const val DELETE_MENU_ICON_TESTING_TAG = "deleteMenuIconTestingTag"
+
 abstract class PageFragment : OnItemClickListener, BaseFragment(), FragmentActivityExtensions {
   abstract val pageViewModel: PageViewModel<*, *>
 
@@ -74,7 +87,26 @@ abstract class PageFragment : OnItemClickListener, BaseFragment(), FragmentActiv
   abstract val searchQueryHint: String
   abstract val pageAdapter: PageAdapter
   abstract val switchIsChecked: Boolean
-  abstract val deleteIconTitle: String
+  abstract val deleteIconTitle: Int
+  private val pageState: MutableState<PageState<*>> =
+    mutableStateOf(
+      NotesState(
+        emptyList(),
+        true,
+        ""
+      ),
+      policy = referentialEqualityPolicy()
+    )
+
+  /**
+   * Controls the visibility of the "Switch", and its controls.
+   *
+   * A [Triple] containing:
+   *  - [String]: The text displayed with switch.
+   *  - [Boolean]: Whether the switch is checked or not.
+   *  - [Boolean]: Whether the switch is enabled or disabled.
+   */
+  private val pageSwitchItem = mutableStateOf(Triple("", true, true))
   private var fragmentPageBinding: FragmentPageBinding? = null
   override val fragmentToolbar: Toolbar? by lazy {
     fragmentPageBinding?.root?.findViewById(R.id.toolbar)
@@ -119,7 +151,7 @@ abstract class PageFragment : OnItemClickListener, BaseFragment(), FragmentActiv
               }
             )
           }
-          menu.findItem(R.id.menu_pages_clear).title = deleteIconTitle // Bug fix #3825
+          // menu.findItem(R.id.menu_pages_clear).title = deleteIconTitle // Bug fix #3825
         }
 
         @Suppress("ReturnCount")
@@ -155,16 +187,16 @@ abstract class PageFragment : OnItemClickListener, BaseFragment(), FragmentActiv
     }
     fragmentPageBinding?.noPage?.text = noItemsString
 
-    fragmentPageBinding?.pageSwitch?.apply {
-      text = switchString
-      isChecked = switchIsChecked
-      // hide switches for custom apps, see more info here https://github.com/kiwix/kiwix-android/issues/3523
-      visibility = if (requireActivity().isCustomApp()) GONE else VISIBLE
-    }
+    // fragmentPageBinding?.pageSwitch?.apply {
+    //   text = switchString
+    //   isChecked = switchIsChecked
+    //   // hide switches for custom apps, see more info here https://github.com/kiwix/kiwix-android/issues/3523
+    //   visibility = if (requireActivity().isCustomApp()) GONE else VISIBLE
+    // }
     compositeDisposable.add(pageViewModel.effects.subscribe { it.invokeWith(activity) })
-    fragmentPageBinding?.pageSwitch?.setOnCheckedChangeListener { _, isChecked ->
-      pageViewModel.actions.offer(Action.UserClickedShowAllToggle(isChecked))
-    }
+    // fragmentPageBinding?.pageSwitch?.setOnCheckedChangeListener { _, isChecked ->
+    //   pageViewModel.actions.offer(Action.UserClickedShowAllToggle(isChecked))
+    // }
     pageViewModel.state.observe(viewLifecycleOwner, Observer(::render))
 
     // hides keyboard when scrolled
@@ -184,38 +216,85 @@ abstract class PageFragment : OnItemClickListener, BaseFragment(), FragmentActiv
   ): View? {
     return ComposeView(requireContext()).apply {
       setContent {
+        val isSearchActive = remember { mutableStateOf(false) }
         PageScreen(
-          pageState = pageViewModel.state,
-          effects = pageViewModel.effects,
+          pageState = pageState.value,
+          pageSwitchItem = pageSwitchItem.value,
           screenTitle = screenTitle,
           noItemsString = noItemsString,
-          switchString = switchString,
           searchQueryHint = searchQueryHint,
-          switchIsChecked = switchIsChecked,
-          onSwitchChanged = { isChecked ->
-            pageViewModel.actions.offer(Action.UserClickedShowAllToggle(isChecked))
+          onSwitchChanged = { onSwitchCheckedChanged(it) },
+          itemClickListener = this@PageFragment,
+          navigationIcon = {
+            NavigationIcon(
+              iconItem = navigationIconItem(isSearchActive.value),
+              onClick = navigationIconClick(isSearchActive)
+            )
           },
-          onItemClick = { pageViewModel.actions.offer(Action.OnItemClick(it)) },
-          onItemLongClick = { pageViewModel.actions.offer(Action.OnItemLongClick(it)) }
+          actionMenuItems = actionMenuList(
+            isSearchActive = isSearchActive.value,
+            onSearchClick = { isSearchActive.value = true },
+            onDeleteClick = { pageViewModel.actions.offer(Action.UserClickedDeleteButton) }
+          )
         )
       }
     }
   }
 
+  private fun onSwitchCheckedChanged(isChecked: Boolean): () -> Unit = {
+    pageSwitchItem.value = pageSwitchItem.value.copy(second = isChecked)
+    pageViewModel.actions.offer(Action.UserClickedShowAllToggle(isChecked))
+  }
+
+  private fun navigationIconItem(isSearchActive: Boolean) = if (isSearchActive) {
+    IconItem.Drawable(R.drawable.ic_close_white_24dp)
+  } else {
+    IconItem.Vector(Icons.AutoMirrored.Filled.ArrowBack)
+  }
+
+  private fun navigationIconClick(isSearchActive: MutableState<Boolean>): () -> Unit = {
+    if (isSearchActive.value) {
+      isSearchActive.value = false
+      pageViewModel.actions.offer(Action.Exit)
+    } else {
+      requireActivity().onBackPressedDispatcher.onBackPressed()
+    }
+  }
+
+  private fun actionMenuList(
+    isSearchActive: Boolean,
+    onSearchClick: () -> Unit,
+    onDeleteClick: () -> Unit
+  ): List<ActionMenuItem> {
+    return listOfNotNull(
+      when {
+        !isSearchActive -> ActionMenuItem(
+          icon = IconItem.Drawable(R.drawable.action_search),
+          contentDescription = R.string.search_label,
+          onClick = onSearchClick,
+          testingTag = SEARCH_ICON_TESTING_TAG
+        )
+
+        else -> null
+      },
+      ActionMenuItem(
+        icon = IconItem.Vector(Icons.Default.Delete),
+        // Adding content description for #3825.
+        contentDescription = deleteIconTitle,
+        onClick = onDeleteClick,
+        testingTag = DELETE_MENU_ICON_TESTING_TAG
+      )
+    )
+  }
+
   override fun onDestroyView() {
     super.onDestroyView()
     compositeDisposable.clear()
-    fragmentPageBinding?.apply {
-      recyclerView.adapter = null
-      root.removeAllViews()
-    }
-    fragmentPageBinding = null
   }
 
   private fun render(state: PageState<*>) {
-    pageAdapter.items = state.visiblePageItems
-    fragmentPageBinding?.pageSwitch?.isEnabled = !state.isInSelectionState
-    fragmentPageBinding?.noPage?.visibility = if (state.pageItems.isEmpty()) VISIBLE else GONE
+    pageState.value = state
+    pageSwitchItem.value = Triple(switchString, switchIsChecked, !state.isInSelectionState)
     if (state.isInSelectionState) {
       if (actionMode == null) {
         actionMode =

core/src/main/java/org/kiwix/kiwixmobile/core/page/PageListItem.kt

@@ -39,6 +39,7 @@ import androidx.compose.ui.text.style.TextOverflow
 import org.kiwix.kiwixmobile.core.R
 import org.kiwix.kiwixmobile.core.downloader.model.Base64String
 import org.kiwix.kiwixmobile.core.downloader.model.toPainter
+import org.kiwix.kiwixmobile.core.page.adapter.OnItemClickListener
 import org.kiwix.kiwixmobile.core.page.adapter.Page
 import org.kiwix.kiwixmobile.core.utils.ComposeDimens.EIGHT_DP
 import org.kiwix.kiwixmobile.core.utils.ComposeDimens.PAGE_LIST_ITEM_FAVICON_SIZE
@@ -48,13 +49,15 @@ import org.kiwix.kiwixmobile.core.utils.ComposeDimens.SIXTEEN_DP
 @Composable
 fun PageListItem(
   page: Page,
-  onClick: () -> Unit,
-  onLongClick: () -> Unit
+  itemClickListener: OnItemClickListener
 ) {
   Row(
     modifier = Modifier
       .fillMaxWidth()
-      .combinedClickable(onClick = onClick, onLongClick = onLongClick)
+      .combinedClickable(
+        onClick = { itemClickListener.onItemClick(page) },
+        onLongClick = { itemClickListener.onItemLongClick(page) }
+      )
       .background(MaterialTheme.colorScheme.surface)
       .padding(
         horizontal = SIXTEEN_DP,

core/src/main/java/org/kiwix/kiwixmobile/core/page/PageScreen.kt

@@ -32,55 +32,51 @@ import androidx.compose.material3.Scaffold
 import androidx.compose.material3.Switch
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.LaunchedEffect
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.livedata.observeAsState
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
-import androidx.lifecycle.MutableLiveData
-import io.reactivex.processors.PublishProcessor
-import org.kiwix.kiwixmobile.core.base.SideEffect
 import org.kiwix.kiwixmobile.core.extensions.ActivityExtensions.isCustomApp
 import org.kiwix.kiwixmobile.core.main.CoreMainActivity
+import org.kiwix.kiwixmobile.core.page.adapter.OnItemClickListener
 import org.kiwix.kiwixmobile.core.page.adapter.Page
 import org.kiwix.kiwixmobile.core.page.history.adapter.HistoryListItem.DateItem
 import org.kiwix.kiwixmobile.core.page.viewmodel.PageState
 import org.kiwix.kiwixmobile.core.ui.components.KiwixAppBar
+import org.kiwix.kiwixmobile.core.ui.models.ActionMenuItem
 import org.kiwix.kiwixmobile.core.ui.theme.KiwixTheme
 import org.kiwix.kiwixmobile.core.utils.ComposeDimens.EIGHT_DP
 import org.kiwix.kiwixmobile.core.utils.ComposeDimens.SIXTEEN_DP
 
-@Suppress("LongParameterList", "IgnoredReturnValue", "UnusedParameter")
+@Suppress(
+  "LongParameterList",
+  "IgnoredReturnValue",
+  "UnusedParameter",
+  "ComposableLambdaParameterNaming"
+)
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun PageScreen(
-  pageState: MutableLiveData<out PageState<out Page>>,
-  effects: PublishProcessor<SideEffect<*>>,
+  pageState: PageState<out Page>,
+  pageSwitchItem: Triple<String, Boolean, Boolean>,
   screenTitle: Int,
   noItemsString: String,
-  switchString: String,
   searchQueryHint: String,
-  switchIsChecked: Boolean,
   onSwitchChanged: (Boolean) -> Unit,
-  onItemClick: (Page) -> Unit,
-  onItemLongClick: (Page) -> Unit
+  itemClickListener: OnItemClickListener,
+  actionMenuItems: List<ActionMenuItem>,
+  navigationIcon: @Composable () -> Unit,
 ) {
   val context = LocalActivity.current as CoreMainActivity
 
-  val state by pageState.observeAsState()
-
-  LaunchedEffect(Unit) {
-    effects.subscribe { it.invokeWith(context) }
-  }
-
   KiwixTheme {
     Scaffold(
       topBar = {
         Column {
           KiwixAppBar(
             titleId = screenTitle,
-            navigationIcon = {},
+            navigationIcon = navigationIcon,
+            actionMenuItems = actionMenuItems
           )
+          // hide switches for custom apps, see more info here https://github.com/kiwix/kiwix-android/issues/3523
           if (!context.isCustomApp()) {
             Row(
               modifier = Modifier
@@ -88,14 +84,18 @@ fun PageScreen(
                 .padding(horizontal = SIXTEEN_DP, vertical = EIGHT_DP),
               verticalAlignment = Alignment.CenterVertically
             ) {
-              Text(switchString, modifier = Modifier.weight(1f))
-              Switch(checked = switchIsChecked, onCheckedChange = onSwitchChanged)
+              Text(pageSwitchItem.first, modifier = Modifier.weight(1f))
+              Switch(
+                checked = pageSwitchItem.second,
+                onCheckedChange = onSwitchChanged,
+                enabled = pageSwitchItem.third
+              )
             }
           }
         }
       }
     ) { padding ->
-      val items = state?.visiblePageItems.orEmpty()
+      val items = pageState.pageItems
       Box(modifier = Modifier.padding(padding)) {
         if (items.isEmpty()) {
           Text(
@@ -105,13 +105,12 @@ fun PageScreen(
           )
         } else {
           LazyColumn {
-            items(items) { item ->
+            items(pageState.visiblePageItems) { item ->
               when (item) {
                 is Page -> {
                   PageListItem(
                     page = item,
-                    onClick = { onItemClick(item) },
-                    onLongClick = { onItemLongClick(item) }
+                    itemClickListener = itemClickListener
                   )
                 }
 

core/src/main/java/org/kiwix/kiwixmobile/core/page/bookmark/BookmarksFragment.kt

@@ -19,8 +19,8 @@ class BookmarksFragment : PageFragment() {
   override val screenTitle: Int by lazy { R.string.bookmarks }
   override val noItemsString: String by lazy { getString(R.string.no_bookmarks) }
   override val switchString: String by lazy { getString(R.string.bookmarks_from_current_book) }
-  override val deleteIconTitle: String by lazy {
-    getString(R.string.pref_clear_all_bookmarks_title)
+  override val deleteIconTitle: Int by lazy {
+    R.string.pref_clear_all_bookmarks_title
   }
   override val switchIsChecked: Boolean by lazy { sharedPreferenceUtil.showBookmarksAllBooks }
 

core/src/main/java/org/kiwix/kiwixmobile/core/page/history/HistoryFragment.kt

@@ -22,8 +22,8 @@ class HistoryFragment : PageFragment() {
   override val noItemsString: String by lazy { getString(R.string.no_history) }
   override val switchString: String by lazy { getString(R.string.history_from_current_book) }
   override val screenTitle: Int by lazy { R.string.history }
-  override val deleteIconTitle: String by lazy {
-    getString(R.string.pref_clear_all_history_title)
+  override val deleteIconTitle: Int by lazy {
+    R.string.pref_clear_all_history_title
   }
   override val switchIsChecked: Boolean by lazy { sharedPreferenceUtil.showHistoryAllBooks }
 

core/src/main/java/org/kiwix/kiwixmobile/core/page/notes/NotesFragment.kt

@@ -38,8 +38,8 @@ class NotesFragment : PageFragment() {
 
   override val noItemsString: String by lazy { getString(R.string.no_notes) }
   override val switchString: String by lazy { getString(R.string.notes_from_all_books) }
-  override val deleteIconTitle: String by lazy {
-    getString(R.string.pref_clear_notes)
+  override val deleteIconTitle: Int by lazy {
+    R.string.pref_clear_notes
   }
   override val switchIsChecked: Boolean by lazy { sharedPreferenceUtil.showNotesAllBooks }