added placeholder for empty custom films list

lib/providers/films_provider.dart

@@ -95,7 +95,6 @@ class FilmsProviderState extends State<FilmsProvider> {
     setState(() {});
   }
 
-  // TODO: add delete button to UI
   void deleteCustomFilm(FilmExponential film) {
     customFilms.remove(film.id);
     _discardSelectedIfNotIncluded();
@@ -170,12 +169,7 @@ class Films extends InheritedModel<_FilmsModelAspect> {
 
   @override
   bool updateShouldNotifyDependent(Films oldWidget, Set<_FilmsModelAspect> dependencies) {
-    if (dependencies.contains(_FilmsModelAspect.customFilmsList)) {}
+    // TODO: reduce unnecessary notifications
-    if (dependencies.contains(_FilmsModelAspect.selected)) {
+    return true;
-      return selected != oldWidget.selected;
-    } else {
-      // TODO: reduce unnecessary notifications
-      return true;
-    }
   }
 }

lib/screens/films/screen_films.dart

@@ -4,6 +4,7 @@ import 'package:lightmeter/navigation/routes.dart';
 import 'package:lightmeter/providers/films_provider.dart';
 import 'package:lightmeter/res/dimens.dart';
 import 'package:lightmeter/screens/film_edit/flow_film_edit.dart';
+import 'package:lightmeter/screens/shared/sliver_placeholder/widget_sliver_placeholder.dart';
 import 'package:lightmeter/screens/shared/sliver_screen/screen_sliver.dart';
 import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';
 
@@ -17,6 +18,14 @@ class FilmsScreen extends StatefulWidget {
 class _FilmsScreenState extends State<FilmsScreen> with SingleTickerProviderStateMixin {
   late final tabController = TabController(length: 2, vsync: this);
 
+  @override
+  void initState() {
+    super.initState();
+    tabController.addListener(() {
+      setState(() {});
+    });
+  }
+
   @override
   void dispose() {
     tabController.dispose();
@@ -50,22 +59,19 @@ class _FilmsScreenState extends State<FilmsScreen> with SingleTickerProviderStat
         ),
       ],
       slivers: [
-        SliverFillRemaining(
+        if (tabController.index == 0)
-          child: TabBarView(
+          _FilmsListBuilder(
-            controller: tabController,
+            films: Films.predefinedFilmsOf(context).toList(),
-            children: [
+            onFilmSelected: FilmsProvider.of(context).toggleFilm,
-              _FilmsListBuilder(
+          )
-                films: Films.predefinedFilmsOf(context).toList(),
+        else if (tabController.index == 1 && Films.customFilmsOf(context).isNotEmpty)
-                onFilmSelected: FilmsProvider.of(context).toggleFilm,
+          _FilmsListBuilder<FilmExponential>(
-              ),
+            films: Films.customFilmsOf(context).toList(),
-              _FilmsListBuilder<FilmExponential>(
+            onFilmSelected: FilmsProvider.of(context).toggleFilm,
-                films: Films.customFilmsOf(context).toList(),
+            onFilmEdit: _editFilm,
-                onFilmSelected: FilmsProvider.of(context).toggleFilm,
+          )
-                onFilmEdit: _editFilm,
+        else
-              ),
+          SliverPlaceholder(onTap: _addFilm),
-            ],
-          ),
-        ),
       ],
     );
   }
@@ -98,36 +104,41 @@ class _FilmsListBuilder<T extends Film> extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return ListView.builder(
+    return SliverList.builder(
-      padding: const EdgeInsets.all(Dimens.paddingM).add(EdgeInsets.only(bottom: MediaQuery.paddingOf(context).bottom)),
       itemCount: films.length,
-      itemBuilder: (_, index) => Card(
+      itemBuilder: (_, index) => Padding(
-        shape: RoundedRectangleBorder(
+        padding: EdgeInsets.fromLTRB(
-          borderRadius: BorderRadius.only(
+          Dimens.paddingM,
-            topLeft: index == 0 ? const Radius.circular(Dimens.borderRadiusL) : Radius.zero,
+          index == 0 ? Dimens.paddingM : 0,
-            topRight: index == 0 ? const Radius.circular(Dimens.borderRadiusL) : Radius.zero,
+          Dimens.paddingM,
-            bottomLeft: index == films.length - 1 ? const Radius.circular(Dimens.borderRadiusL) : Radius.zero,
+          index == films.length - 1 ? Dimens.paddingM + MediaQuery.paddingOf(context).bottom : 0.0,
-            bottomRight: index == films.length - 1 ? const Radius.circular(Dimens.borderRadiusL) : Radius.zero,
-          ),
         ),
-        child: Padding(
+        child: Card(
-          padding: EdgeInsets.only(
+          shape: RoundedRectangleBorder(
-            top: index == 0 ? Dimens.paddingM : 0.0,
+            borderRadius: BorderRadius.vertical(
-            bottom: index == films.length - 1 ? Dimens.paddingM : 0.0,
+              top: index == 0 ? const Radius.circular(Dimens.borderRadiusL) : Radius.zero,
+              bottom: index == films.length - 1 ? const Radius.circular(Dimens.borderRadiusL) : Radius.zero,
+            ),
           ),
-          child: CheckboxListTile(
+          child: Padding(
-            controlAffinity: ListTileControlAffinity.leading,
+            padding: EdgeInsets.only(
-            value: Films.inUseOf(context).contains(films[index]),
+              top: index == 0 ? Dimens.paddingM : 0.0,
-            title: Text(films[index].name),
+              bottom: index == films.length - 1 ? Dimens.paddingM : 0.0,
-            onChanged: (value) {
+            ),
-              onFilmSelected(films[index], value ?? false);
+            child: CheckboxListTile(
-            },
+              controlAffinity: ListTileControlAffinity.leading,
-            secondary: onFilmEdit != null
+              value: Films.inUseOf(context).contains(films[index]),
-                ? IconButton(
+              title: Text(films[index].name),
-                    onPressed: () => onFilmEdit!(films[index]),
+              onChanged: (value) {
-                    icon: const Icon(Icons.edit),
+                onFilmSelected(films[index], value ?? false);
-                  )
+              },
-                : null,
+              secondary: onFilmEdit != null
+                  ? IconButton(
+                      onPressed: () => onFilmEdit!(films[index]),
+                      icon: const Icon(Icons.edit),
+                    )
+                  : null,
+            ),
           ),
         ),
       ),

lib/screens/settings/components/metering/components/equipment_profiles/components/equipment_profile_screen/screen_equipment_profile.dart

@@ -4,7 +4,7 @@ import 'package:lightmeter/providers/equipment_profile_provider.dart';
 import 'package:lightmeter/res/dimens.dart';
 import 'package:lightmeter/screens/settings/components/metering/components/equipment_profiles/components/equipment_profile_screen/components/equipment_profile_container/widget_container_equipment_profile.dart';
 import 'package:lightmeter/screens/settings/components/metering/components/equipment_profiles/components/equipment_profile_screen/components/equipment_profile_name_dialog/widget_dialog_equipment_profile_name.dart';
-import 'package:lightmeter/screens/shared/icon_placeholder/widget_icon_placeholder.dart';
+import 'package:lightmeter/screens/shared/sliver_placeholder/widget_sliver_placeholder.dart';
 import 'package:lightmeter/screens/shared/sliver_screen/screen_sliver.dart';
 import 'package:m3_lightmeter_resources/m3_lightmeter_resources.dart';
 
@@ -37,12 +37,7 @@ class _EquipmentProfilesScreenState extends State<EquipmentProfilesScreen> {
         ),
       ],
       slivers: profilesCount == 1
-          ? [
+          ? [SliverPlaceholder(onTap: _addProfile)]
-              SliverFillRemaining(
-                hasScrollBody: false,
-                child: _EquipmentProfilesListPlaceholder(onTap: _addProfile),
-              ),
-            ]
           : [
               SliverList(
                 delegate: SliverChildBuilderDelegate(
@@ -131,32 +126,3 @@ class _EquipmentProfilesScreenState extends State<EquipmentProfilesScreen> {
     }
   }
 }
-
-class _EquipmentProfilesListPlaceholder extends StatelessWidget {
-  final VoidCallback onTap;
-
-  const _EquipmentProfilesListPlaceholder({required this.onTap});
-
-  @override
-  Widget build(BuildContext context) {
-    return Padding(
-      padding: const EdgeInsets.only(bottom: Dimens.sliverAppBarExpandedHeight),
-      child: FractionallySizedBox(
-        widthFactor: 1 / 1.618,
-        child: Center(
-          child: GestureDetector(
-            behavior: HitTestBehavior.translucent,
-            onTap: onTap,
-            child: Padding(
-              padding: const EdgeInsets.all(Dimens.paddingL),
-              child: IconPlaceholder(
-                icon: Icons.add_outlined,
-                text: S.of(context).tapToAdd,
-              ),
-            ),
-          ),
-        ),
-      ),
-    );
-  }
-}

lib/screens/shared/sliver_placeholder/widget_sliver_placeholder.dart

@@ -0,0 +1,39 @@
+import 'package:flutter/material.dart';
+import 'package:lightmeter/generated/l10n.dart';
+import 'package:lightmeter/res/dimens.dart';
+import 'package:lightmeter/screens/shared/icon_placeholder/widget_icon_placeholder.dart';
+import 'package:lightmeter/screens/shared/sliver_screen/screen_sliver.dart';
+
+class SliverPlaceholder extends StatelessWidget {
+  final VoidCallback onTap;
+
+  const SliverPlaceholder({required this.onTap});
+
+  @override
+  Widget build(BuildContext context) {
+    final sliverScreenBottomHeight =
+        context.findAncestorWidgetOfExactType<SliverScreen>()?.bottom?.preferredSize.height ?? 0.0;
+    return SliverFillRemaining(
+      hasScrollBody: false,
+      child: Padding(
+        padding: EdgeInsets.only(bottom: Dimens.sliverAppBarExpandedHeight - sliverScreenBottomHeight),
+        child: FractionallySizedBox(
+          widthFactor: 1 / 1.618,
+          child: Center(
+            child: GestureDetector(
+              behavior: HitTestBehavior.translucent,
+              onTap: onTap,
+              child: Padding(
+                padding: const EdgeInsets.all(Dimens.paddingL),
+                child: IconPlaceholder(
+                  icon: Icons.add_outlined,
+                  text: S.of(context).tapToAdd,
+                ),
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/screens/shared/sliver_screen/screen_sliver.dart

@@ -25,36 +25,10 @@ class SliverScreen extends StatelessWidget {
         bottom: false,
         child: CustomScrollView(
           slivers: <Widget>[
-            SliverAppBar.large(
+            _AppBar(
-              automaticallyImplyLeading: false,
+              title: title,
-              expandedHeight: Dimens.sliverAppBarExpandedHeight + (bottom?.preferredSize.height ?? 0.0),
+              appBarActions: appBarActions,
-              flexibleSpace: FlexibleSpaceBar(
-                centerTitle: false,
-                titlePadding: const EdgeInsets.symmetric(horizontal: Dimens.paddingM),
-                title: DefaultTextStyle(
-                  style: Theme.of(context)
-                      .textTheme
-                      .headlineSmall!
-                      .copyWith(color: Theme.of(context).colorScheme.onSurface),
-                  maxLines: 2,
-                  overflow: TextOverflow.ellipsis,
-                  child: _Title(
-                    actionsCount: appBarActions.length + (Navigator.of(context).canPop() ? 1 : 0),
-                    bottomSize: bottom?.preferredSize.height ?? 0.0,
-                    child: title,
-                  ),
-                ),
-              ),
               bottom: bottom,
-              actions: [
-                ...appBarActions,
-                if (Navigator.of(context).canPop())
-                  IconButton(
-                    onPressed: Navigator.of(context).pop,
-                    icon: const Icon(Icons.close_outlined),
-                    tooltip: S.of(context).tooltipClose,
-                  ),
-              ],
             ),
             ...slivers,
           ],
@@ -64,6 +38,51 @@ class SliverScreen extends StatelessWidget {
   }
 }
 
+class _AppBar extends StatelessWidget {
+  final Widget title;
+  final List<Widget> appBarActions;
+  final PreferredSizeWidget? bottom;
+
+  const _AppBar({
+    required this.title,
+    this.appBarActions = const [],
+    this.bottom,
+    super.key,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return SliverAppBar.large(
+      automaticallyImplyLeading: false,
+      expandedHeight: Dimens.sliverAppBarExpandedHeight + (bottom?.preferredSize.height ?? 0.0),
+      flexibleSpace: FlexibleSpaceBar(
+        centerTitle: false,
+        titlePadding: const EdgeInsets.symmetric(horizontal: Dimens.paddingM),
+        title: DefaultTextStyle(
+          style: Theme.of(context).textTheme.headlineSmall!.copyWith(color: Theme.of(context).colorScheme.onSurface),
+          maxLines: 2,
+          overflow: TextOverflow.ellipsis,
+          child: _Title(
+            actionsCount: appBarActions.length + (Navigator.of(context).canPop() ? 1 : 0),
+            bottomSize: bottom?.preferredSize.height ?? 0.0,
+            child: title,
+          ),
+        ),
+      ),
+      bottom: bottom,
+      actions: [
+        ...appBarActions,
+        if (Navigator.of(context).canPop())
+          IconButton(
+            onPressed: Navigator.of(context).pop,
+            icon: const Icon(Icons.close_outlined),
+            tooltip: S.of(context).tooltipClose,
+          ),
+      ],
+    );
+  }
+}
+
 class _Title extends StatelessWidget {
   final Widget child;
   final int actionsCount;