Display notification filter/clear actions as menu items (#3877)

Previously the notification filter and clear actions were shown as
buttons in the UI, with a preference that determined whether they were
displayed.

Remove this preference, and display them as menu items.

- "Filter notifications" is shown as an icon, if possible
- "Clear notifications" is only ever shown as a menu item, to reduce the
chance the user inadvertently selects it

To ensure that the options menu appears correctly, remove the code that
creates a "fake" action bar, and adjust the layouts so that there are
three toolbars;

- mainToolbar -- displays the icons, and the current "location" (Home,
Notifications, etc)
- topNav -- displays the row of tabs at the top
- bottomNav -- displays the row of tabs at the bottom

Only one of them is set as the support action bar (depending on the
user's preferences). This provides the "show a logo" and "show the
options menu" functionality as standard, without needing to re-implement
as the previous code did.

app/src/main/java/com/keylesspalace/tusky/components/notifications/NotificationsFragment.kt

@@ -28,7 +28,6 @@ import android.view.MenuItem
 import android.view.View
 import android.view.ViewGroup
 import androidx.appcompat.app.AlertDialog
-import androidx.coordinatorlayout.widget.CoordinatorLayout
 import androidx.core.view.MenuProvider
 import androidx.core.view.isVisible
 import androidx.fragment.app.DialogFragment
@@ -46,7 +45,6 @@ import androidx.recyclerview.widget.RecyclerView.SCROLL_STATE_IDLE
 import androidx.recyclerview.widget.SimpleItemAnimator
 import androidx.swiperefreshlayout.widget.SwipeRefreshLayout.OnRefreshListener
 import at.connyduck.sparkbutton.helpers.Utils
-import com.google.android.material.appbar.AppBarLayout.ScrollingViewBehavior
 import com.google.android.material.color.MaterialColors
 import com.google.android.material.snackbar.Snackbar
 import com.keylesspalace.tusky.R
@@ -123,21 +121,6 @@ class NotificationsFragment :
         return inflater.inflate(R.layout.fragment_timeline_notifications, container, false)
     }
 
-    private fun updateFilterVisibility(showFilter: Boolean) {
-        val params = binding.swipeRefreshLayout.layoutParams as CoordinatorLayout.LayoutParams
-        if (showFilter) {
-            binding.appBarOptions.setExpanded(true, false)
-            binding.appBarOptions.visibility = View.VISIBLE
-            // Set content behaviour to hide filter on scroll
-            params.behavior = ScrollingViewBehavior()
-        } else {
-            binding.appBarOptions.setExpanded(false, false)
-            binding.appBarOptions.visibility = View.GONE
-            // Clear behaviour to hide app bar
-            params.behavior = null
-        }
-    }
-
     private fun confirmClearNotifications() {
         AlertDialog.Builder(requireContext())
             .setMessage(R.string.notification_clear_text)
@@ -215,8 +198,6 @@ class NotificationsFragment :
             footer = NotificationsLoadStateAdapter { adapter.retry() }
         )
 
-        binding.buttonClear.setOnClickListener { confirmClearNotifications() }
-        binding.buttonFilter.setOnClickListener { showFilterDialog() }
         (binding.recyclerView.itemAnimator as SimpleItemAnimator?)!!.supportsChangeAnimations =
             false
 
@@ -369,10 +350,10 @@ class NotificationsFragment :
                     }
                 }
 
-                // Update filter option visibility from uiState
-                launch {
-                    viewModel.uiState.collectLatest { updateFilterVisibility(it.showFilterOptions) }
-                }
+                // Collect the uiState. Nothing is done with it, but if you don't collect it then
+                // accessing viewModel.uiState.value (e.g., when the filter dialog is created)
+                // returns an empty object.
+                launch { viewModel.uiState.collect() }
 
                 // Update status display from statusDisplayOptions. If the new options request
                 // relative time display collect the flow to periodically update the timestamp in the list gui elements.
@@ -439,10 +420,17 @@ class NotificationsFragment :
 
     override fun onCreateMenu(menu: Menu, menuInflater: MenuInflater) {
         menuInflater.inflate(R.menu.fragment_notifications, menu)
+        val iconColor = MaterialColors.getColor(binding.root, android.R.attr.textColorPrimary)
         menu.findItem(R.id.action_refresh)?.apply {
             icon = IconicsDrawable(requireContext(), GoogleMaterial.Icon.gmd_refresh).apply {
                 sizeDp = 20
-                colorInt = MaterialColors.getColor(binding.root, android.R.attr.textColorPrimary)
+                colorInt = iconColor
+            }
+        }
+        menu.findItem(R.id.action_edit_notification_filter)?.apply {
+            icon = IconicsDrawable(requireContext(), GoogleMaterial.Icon.gmd_tune).apply {
+                sizeDp = 20
+                colorInt = iconColor
             }
         }
     }
@@ -458,6 +446,14 @@ class NotificationsFragment :
                 viewModel.accept(InfallibleUiAction.LoadNewest)
                 true
             }
+            R.id.action_edit_notification_filter -> {
+                showFilterDialog()
+                true
+            }
+            R.id.action_clear_notifications -> {
+                confirmClearNotifications()
+                true
+            }
             else -> false
         }
     }
@@ -625,7 +621,6 @@ class NotificationsFragment :
 
     override fun onReselect() {
         if (isAdded) {
-            binding.appBarOptions.setExpanded(true, false)
             layoutManager.scrollToPosition(0)
         }
     }

app/src/main/java/com/keylesspalace/tusky/components/notifications/NotificationsViewModel.kt

@@ -74,23 +74,18 @@ data class UiState(
     /** Filtered notification types */
     val activeFilter: Set<Notification.Type> = emptySet(),
 
-    /** True if the UI to filter and clear notifications should be shown */
-    val showFilterOptions: Boolean = false,
-
     /** True if the FAB should be shown while scrolling */
     val showFabWhileScrolling: Boolean = true
 )
 
 /** Preferences the UI reacts to */
 data class UiPrefs(
-    val showFabWhileScrolling: Boolean,
-    val showFilter: Boolean
+    val showFabWhileScrolling: Boolean
 ) {
     companion object {
         /** Relevant preference keys. Changes to any of these trigger a display update */
         val prefKeys = setOf(
-            PrefKeys.FAB_HIDE,
-            PrefKeys.SHOW_NOTIFICATIONS_FILTER
+            PrefKeys.FAB_HIDE
         )
     }
 }
@@ -495,7 +490,6 @@ class NotificationsViewModel @Inject constructor(
         uiState = combine(notificationFilter, getUiPrefs()) { filter, prefs ->
             UiState(
                 activeFilter = filter.filter,
-                showFilterOptions = prefs.showFilter,
                 showFabWhileScrolling = prefs.showFabWhileScrolling
             )
         }.stateIn(
@@ -544,8 +538,7 @@ class NotificationsViewModel @Inject constructor(
         .onStart { emit(toPrefs()) }
 
     private fun toPrefs() = UiPrefs(
-        showFabWhileScrolling = !preferences.getBoolean(PrefKeys.FAB_HIDE, false),
-        showFilter = preferences.getBoolean(PrefKeys.SHOW_NOTIFICATIONS_FILTER, true)
+        showFabWhileScrolling = !preferences.getBoolean(PrefKeys.FAB_HIDE, false)
     )
 
     companion object {

app/src/main/java/com/keylesspalace/tusky/components/preference/PreferencesFragment.kt

@@ -208,13 +208,6 @@ class PreferencesFragment : PreferenceFragmentCompat(), Injectable {
                     isSingleLineTitle = false
                 }
 
-                switchPreference {
-                    setDefaultValue(true)
-                    key = PrefKeys.SHOW_NOTIFICATIONS_FILTER
-                    setTitle(R.string.pref_title_show_notifications_filter)
-                    isSingleLineTitle = false
-                }
-
                 switchPreference {
                     setDefaultValue(true)
                     key = PrefKeys.CONFIRM_REBLOGS