Rewrite double tap to exit code

app/lib/widget/double_tap_exit_container/bloc.dart

@@ -0,0 +1,63 @@
+part of 'double_tap_exit_container.dart';
+
+@npLog
+class _Bloc extends Bloc<_Event, _State> with BlocLogger {
+  _Bloc({
+    required this.prefController,
+  }) : super(_State.init(
+          isDoubleTapExit: prefController.isDoubleTapExitValue,
+        )) {
+    on<_SetDoubleTapExit>(_onSetDoubleTapExit);
+    on<_SetCanPop>(_onSetCanPop);
+    on<_OnPopInvoked>(_onOnPopInvoked);
+
+    _subscriptions.add(prefController.isDoubleTapExitChange.listen((ev) {
+      add(_SetDoubleTapExit(ev));
+    }));
+  }
+
+  @override
+  Future<void> close() {
+    for (final s in _subscriptions) {
+      s.cancel();
+    }
+    _timer?.cancel();
+    return super.close();
+  }
+
+  @override
+  String get tag => _log.fullName;
+
+  void _onSetDoubleTapExit(_SetDoubleTapExit ev, _Emitter emit) {
+    _log.info(ev);
+    emit(state.copyWith(isDoubleTapExit: ev.value));
+  }
+
+  void _onSetCanPop(_SetCanPop ev, _Emitter emit) {
+    _log.info(ev);
+    emit(state.copyWith(canPop: ev.value));
+  }
+
+  void _onOnPopInvoked(_OnPopInvoked ev, _Emitter emit) {
+    _log.info(ev);
+    if (state.isDoubleTapExit && !state.canPop) {
+      emit(state.copyWith(canPop: true));
+      _timer?.cancel();
+      _timer = Timer(
+        const Duration(seconds: 5),
+        () {
+          add(const _SetCanPop(false));
+        },
+      );
+      SnackBarManager().showSnackBar(SnackBar(
+        content: Text(L10n.global().doubleTapExitNotification),
+        duration: k.snackBarDurationShort,
+      ));
+    }
+  }
+
+  final PrefController prefController;
+
+  final _subscriptions = <StreamSubscription>[];
+  Timer? _timer;
+}

app/lib/widget/double_tap_exit_container/double_tap_exit_container.dart

@@ -0,0 +1,72 @@
+import 'dart:async';
+
+import 'package:copy_with/copy_with.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:logging/logging.dart';
+import 'package:nc_photos/app_localizations.dart';
+import 'package:nc_photos/bloc_util.dart';
+import 'package:nc_photos/controller/pref_controller.dart';
+import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/snack_bar_manager.dart';
+import 'package:np_codegen/np_codegen.dart';
+import 'package:to_string/to_string.dart';
+
+part 'bloc.dart';
+part 'double_tap_exit_container.g.dart';
+part 'state_event.dart';
+
+class DoubleTapExitContainer extends StatelessWidget {
+  const DoubleTapExitContainer({
+    super.key,
+    required this.child,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return BlocProvider(
+      create: (_) => _Bloc(
+        prefController: context.read(),
+      ),
+      child: _WrappedDoubleTapExitContainer(child: child),
+    );
+  }
+
+  final Widget child;
+}
+
+class _WrappedDoubleTapExitContainer extends StatelessWidget {
+  const _WrappedDoubleTapExitContainer({
+    required this.child,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return _BlocBuilder(
+      buildWhen: (previous, current) =>
+          previous.isDoubleTapExit != current.isDoubleTapExit ||
+          previous.canPop != current.canPop,
+      builder: (context, state) => PopScope(
+        canPop: !state.isDoubleTapExit || state.canPop,
+        onPopInvoked: (didPop) {
+          context.addEvent(_OnPopInvoked(didPop));
+        },
+        child: child,
+      ),
+    );
+  }
+
+  final Widget child;
+}
+
+typedef _BlocBuilder = BlocBuilder<_Bloc, _State>;
+// typedef _BlocListener = BlocListener<_Bloc, _State>;
+// typedef _BlocListenerT<T> = BlocListenerT<_Bloc, _State, T>;
+// typedef _BlocSelector<T> = BlocSelector<_Bloc, _State, T>;
+typedef _Emitter = Emitter<_State>;
+
+extension on BuildContext {
+  _Bloc get bloc => read<_Bloc>();
+  // _State get state => bloc.state;
+  void addEvent(_Event event) => bloc.add(event);
+}

app/lib/widget/double_tap_exit_container/double_tap_exit_container.g.dart

@@ -0,0 +1,79 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'double_tap_exit_container.dart';
+
+// **************************************************************************
+// CopyWithLintRuleGenerator
+// **************************************************************************
+
+// ignore_for_file: library_private_types_in_public_api, duplicate_ignore
+
+// **************************************************************************
+// CopyWithGenerator
+// **************************************************************************
+
+abstract class $_StateCopyWithWorker {
+  _State call({bool? isDoubleTapExit, bool? canPop});
+}
+
+class _$_StateCopyWithWorkerImpl implements $_StateCopyWithWorker {
+  _$_StateCopyWithWorkerImpl(this.that);
+
+  @override
+  _State call({dynamic isDoubleTapExit, dynamic canPop}) {
+    return _State(
+        isDoubleTapExit: isDoubleTapExit as bool? ?? that.isDoubleTapExit,
+        canPop: canPop as bool? ?? that.canPop);
+  }
+
+  final _State that;
+}
+
+extension $_StateCopyWith on _State {
+  $_StateCopyWithWorker get copyWith => _$copyWith;
+  $_StateCopyWithWorker get _$copyWith => _$_StateCopyWithWorkerImpl(this);
+}
+
+// **************************************************************************
+// NpLogGenerator
+// **************************************************************************
+
+extension _$_BlocNpLog on _Bloc {
+  // ignore: unused_element
+  Logger get _log => log;
+
+  static final log = Logger(
+      "widget.double_tap_exit_container.double_tap_exit_container._Bloc");
+}
+
+// **************************************************************************
+// ToStringGenerator
+// **************************************************************************
+
+extension _$_StateToString on _State {
+  String _$toString() {
+    // ignore: unnecessary_string_interpolations
+    return "_State {isDoubleTapExit: $isDoubleTapExit, canPop: $canPop}";
+  }
+}
+
+extension _$_SetDoubleTapExitToString on _SetDoubleTapExit {
+  String _$toString() {
+    // ignore: unnecessary_string_interpolations
+    return "_SetDoubleTapExit {value: $value}";
+  }
+}
+
+extension _$_SetCanPopToString on _SetCanPop {
+  String _$toString() {
+    // ignore: unnecessary_string_interpolations
+    return "_SetCanPop {value: $value}";
+  }
+}
+
+extension _$_OnPopInvokedToString on _OnPopInvoked {
+  String _$toString() {
+    // ignore: unnecessary_string_interpolations
+    return "_OnPopInvoked {didPop: $didPop}";
+  }
+}

app/lib/widget/double_tap_exit_container/state_event.dart

@@ -0,0 +1,56 @@
+part of 'double_tap_exit_container.dart';
+
+@genCopyWith
+@toString
+class _State {
+  const _State({
+    required this.isDoubleTapExit,
+    required this.canPop,
+  });
+
+  factory _State.init({
+    required bool isDoubleTapExit,
+  }) =>
+      _State(
+        isDoubleTapExit: isDoubleTapExit,
+        canPop: false,
+      );
+
+  @override
+  String toString() => _$toString();
+
+  final bool isDoubleTapExit;
+  final bool canPop;
+}
+
+abstract class _Event {}
+
+@toString
+class _SetDoubleTapExit implements _Event {
+  const _SetDoubleTapExit(this.value);
+
+  @override
+  String toString() => _$toString();
+
+  final bool value;
+}
+
+@toString
+class _SetCanPop implements _Event {
+  const _SetCanPop(this.value);
+
+  @override
+  String toString() => _$toString();
+
+  final bool value;
+}
+
+@toString
+class _OnPopInvoked implements _Event {
+  const _OnPopInvoked(this.didPop);
+
+  @override
+  String toString() => _$toString();
+
+  final bool didPop;
+}

app/lib/widget/handler/double_tap_exit_handler.dart

@@ -1,35 +0,0 @@
-import 'package:clock/clock.dart';
-import 'package:flutter/material.dart';
-import 'package:nc_photos/app_localizations.dart';
-import 'package:nc_photos/entity/pref.dart';
-import 'package:nc_photos/k.dart' as k;
-import 'package:nc_photos/snack_bar_manager.dart';
-
-class DoubleTapExitHandler {
-  factory DoubleTapExitHandler() => _inst;
-
-  DoubleTapExitHandler._();
-
-  /// Return if this back button event should actually exit the app
-  bool call() {
-    if (!Pref().isDoubleTapExitOr()) {
-      return true;
-    }
-    final now = clock.now().toUtc();
-    _lastBackButtonAt ??= now.subtract(const Duration(days: 1));
-    if (now.difference(_lastBackButtonAt!) < const Duration(seconds: 5)) {
-      return true;
-    } else {
-      _lastBackButtonAt = now;
-      SnackBarManager().showSnackBar(SnackBar(
-        content: Text(L10n.global().doubleTapExitNotification),
-        duration: k.snackBarDurationShort,
-      ));
-      return false;
-    }
-  }
-
-  static final _inst = DoubleTapExitHandler._();
-
-  DateTime? _lastBackButtonAt;
-}

app/lib/widget/home_collections.dart

@@ -33,9 +33,9 @@ import 'package:nc_photos/widget/album_importer.dart';
 import 'package:nc_photos/widget/archive_browser.dart';
 import 'package:nc_photos/widget/collection_browser.dart';
 import 'package:nc_photos/widget/collection_grid_item.dart';
+import 'package:nc_photos/widget/double_tap_exit_container/double_tap_exit_container.dart';
 import 'package:nc_photos/widget/enhanced_photo_browser.dart';
 import 'package:nc_photos/widget/fade_out_list.dart';
-import 'package:nc_photos/widget/handler/double_tap_exit_handler.dart';
 import 'package:nc_photos/widget/home_app_bar.dart';
 import 'package:nc_photos/widget/map_browser.dart';
 import 'package:nc_photos/widget/navigation_bar_blur_filter.dart';
@@ -46,7 +46,6 @@ import 'package:nc_photos/widget/selection_app_bar.dart';
 import 'package:nc_photos/widget/sharing_browser.dart';
 import 'package:nc_photos/widget/trashbin_browser.dart';
 import 'package:np_codegen/np_codegen.dart';
-import 'package:np_platform_util/np_platform_util.dart';
 import 'package:np_ui/np_ui.dart';
 import 'package:to_string/to_string.dart';
 
@@ -96,7 +95,7 @@ class _WrappedHomeCollectionsState extends State<_WrappedHomeCollections>
 
   @override
   Widget build(BuildContext context) {
-    final content = MultiBlocListener(
+    return MultiBlocListener(
       listeners: [
         _BlocListener(
           listenWhen: (previous, current) =>
@@ -127,103 +126,108 @@ class _WrappedHomeCollectionsState extends State<_WrappedHomeCollections>
           },
         ),
       ],
-      child: Stack(
+      child: _BlocSelector(
-        children: [
+        selector: (state) => state.selectedItems.isEmpty,
-          RefreshIndicator(
+        builder: (context, isSelectedEmpty) => isSelectedEmpty
-            onRefresh: () async {
+            ? const DoubleTapExitContainer(
-              _bloc.add(const _ReloadCollections());
+                child: _BodyView(),
-              await _bloc.stream.first;
+              )
-            },
+            : PopScope(
-            child: CustomScrollView(
+                canPop: false,
-              slivers: [
+                onPopInvoked: (_) {
-                _BlocBuilder(
+                  context.addEvent(const _SetSelectedItems(items: {}));
-                  buildWhen: (previous, current) =>
+                },
-                      previous.selectedItems.isEmpty !=
+                child: const _BodyView(),
-                      current.selectedItems.isEmpty,
+              ),
-                  builder: (context, state) => state.selectedItems.isEmpty
-                      ? const _AppBar()
-                      : const _SelectionAppBar(),
-                ),
-                const SliverToBoxAdapter(
-                  child: SizedBox(height: 8),
-                ),
-                _BlocBuilder(
-                  buildWhen: (previous, current) =>
-                      previous.transformedItems != current.transformedItems ||
-                      previous.selectedItems != current.selectedItems,
-                  builder: (context, state) => SliverPadding(
-                    padding: const EdgeInsets.symmetric(horizontal: 8),
-                    sliver: SelectableItemList(
-                      maxCrossAxisExtent: 256,
-                      childBorderRadius: BorderRadius.zero,
-                      indicatorAlignment: const Alignment(-.92, -.92),
-                      items: state.transformedItems,
-                      itemBuilder: (_, __, item) {
-                        return _BlocSelector<int?>(
-                          selector: (state) =>
-                              state.itemCounts[item.collection.id],
-                          builder: (context, itemCount) => _ItemView(
-                            account: _bloc.account,
-                            item: item,
-                            collectionItemCountOverride: itemCount,
-                          ),
-                        );
-                      },
-                      staggeredTileBuilder: (_, __) =>
-                          const StaggeredTile.count(1, 1),
-                      selectedItems: state.selectedItems,
-                      onSelectionChange: (_, selected) {
-                        _bloc.add(_SetSelectedItems(items: selected.cast()));
-                      },
-                      onItemTap: (context, _, item) {
-                        Navigator.of(context).pushNamed(
-                          CollectionBrowser.routeName,
-                          arguments:
-                              CollectionBrowserArguments(item.collection),
-                        );
-                      },
-                    ),
-                  ),
-                ),
-                SliverToBoxAdapter(
-                  child: SizedBox(
-                    height: AppDimension.of(context).homeBottomAppBarHeight,
-                  ),
-                ),
-              ],
-            ),
-          ),
-          Align(
-            alignment: Alignment.bottomCenter,
-            child: NavigationBarBlurFilter(
-              height: AppDimension.of(context).homeBottomAppBarHeight,
-            ),
-          ),
-        ],
       ),
     );
-    if (getRawPlatform() == NpPlatform.android) {
-      return WillPopScope(
-        onWillPop: () => _onBackButtonPressed(context),
-        child: content,
-      );
-    } else {
-      return content;
-    }
-  }
-
-  Future<bool> _onBackButtonPressed(BuildContext context) async {
-    if (context.state.selectedItems.isEmpty) {
-      return DoubleTapExitHandler()();
-    } else {
-      context.addEvent(const _SetSelectedItems(items: {}));
-      return false;
-    }
   }
 
   late final _Bloc _bloc = context.read();
 }
 
+class _BodyView extends StatelessWidget {
+  const _BodyView();
+
+  @override
+  Widget build(BuildContext context) {
+    return Stack(
+      children: [
+        RefreshIndicator(
+          onRefresh: () async {
+            context.addEvent(const _ReloadCollections());
+            await context.bloc.stream.first;
+          },
+          child: CustomScrollView(
+            slivers: [
+              _BlocBuilder(
+                buildWhen: (previous, current) =>
+                    previous.selectedItems.isEmpty !=
+                    current.selectedItems.isEmpty,
+                builder: (context, state) => state.selectedItems.isEmpty
+                    ? const _AppBar()
+                    : const _SelectionAppBar(),
+              ),
+              const SliverToBoxAdapter(
+                child: SizedBox(height: 8),
+              ),
+              _BlocBuilder(
+                buildWhen: (previous, current) =>
+                    previous.transformedItems != current.transformedItems ||
+                    previous.selectedItems != current.selectedItems,
+                builder: (context, state) => SliverPadding(
+                  padding: const EdgeInsets.symmetric(horizontal: 8),
+                  sliver: SelectableItemList(
+                    maxCrossAxisExtent: 256,
+                    childBorderRadius: BorderRadius.zero,
+                    indicatorAlignment: const Alignment(-.92, -.92),
+                    items: state.transformedItems,
+                    itemBuilder: (_, __, item) {
+                      return _BlocSelector<int?>(
+                        selector: (state) =>
+                            state.itemCounts[item.collection.id],
+                        builder: (context, itemCount) => _ItemView(
+                          account: context.bloc.account,
+                          item: item,
+                          collectionItemCountOverride: itemCount,
+                        ),
+                      );
+                    },
+                    staggeredTileBuilder: (_, __) =>
+                        const StaggeredTile.count(1, 1),
+                    selectedItems: state.selectedItems,
+                    onSelectionChange: (_, selected) {
+                      context
+                          .addEvent(_SetSelectedItems(items: selected.cast()));
+                    },
+                    onItemTap: (context, _, item) {
+                      Navigator.of(context).pushNamed(
+                        CollectionBrowser.routeName,
+                        arguments: CollectionBrowserArguments(item.collection),
+                      );
+                    },
+                  ),
+                ),
+              ),
+              SliverToBoxAdapter(
+                child: SizedBox(
+                  height: AppDimension.of(context).homeBottomAppBarHeight,
+                ),
+              ),
+            ],
+          ),
+        ),
+        Align(
+          alignment: Alignment.bottomCenter,
+          child: NavigationBarBlurFilter(
+            height: AppDimension.of(context).homeBottomAppBarHeight,
+          ),
+        ),
+      ],
+    );
+  }
+}
+
 typedef _BlocBuilder = BlocBuilder<_Bloc, _State>;
 typedef _BlocListener = BlocListener<_Bloc, _State>;
 // typedef _BlocListenerT<T> = BlocListenerT<_Bloc, _State, T>;

app/lib/widget/home_photos2.dart

@@ -45,9 +45,9 @@ import 'package:nc_photos/theme/dimension.dart';
 import 'package:nc_photos/url_launcher_util.dart';
 import 'package:nc_photos/widget/collection_browser.dart';
 import 'package:nc_photos/widget/collection_picker.dart';
+import 'package:nc_photos/widget/double_tap_exit_container/double_tap_exit_container.dart';
 import 'package:nc_photos/widget/file_sharer_dialog.dart';
 import 'package:nc_photos/widget/finger_listener.dart';
-import 'package:nc_photos/widget/handler/double_tap_exit_handler.dart';
 import 'package:nc_photos/widget/home_app_bar.dart';
 import 'package:nc_photos/widget/navigation_bar_blur_filter.dart';
 import 'package:nc_photos/widget/network_thumbnail.dart';
@@ -64,7 +64,6 @@ import 'package:np_common/object_util.dart';
 import 'package:np_common/or_null.dart';
 import 'package:np_datetime/np_datetime.dart';
 import 'package:np_db/np_db.dart';
-import 'package:np_platform_util/np_platform_util.dart';
 import 'package:np_ui/np_ui.dart';
 import 'package:to_string/to_string.dart';
 import 'package:visibility_detector/visibility_detector.dart';
@@ -116,12 +115,12 @@ class _WrappedHomePhotosState extends State<_WrappedHomePhotos> {
   @override
   void initState() {
     super.initState();
-    _bloc.add(const _LoadItems());
+    context.addEvent(const _LoadItems());
   }
 
   @override
   Widget build(BuildContext context) {
-    final content = VisibilityDetector(
+    return VisibilityDetector(
       key: _key,
       onVisibilityChanged: (info) {
         final isVisible = info.visibleFraction >= 0.2;
@@ -177,47 +176,49 @@ class _WrappedHomePhotosState extends State<_WrappedHomePhotos> {
             },
           ),
         ],
-        child: _BlocSelector<bool>(
+        child: _BlocSelector(
-          selector: (state) =>
+          selector: (state) => state.selectedItems.isEmpty,
-              state.files.isEmpty && state.syncProgress != null,
+          builder: (context, isSelectedEmpty) => isSelectedEmpty
-          builder: (context, isInitialSyncing) {
+              ? const DoubleTapExitContainer(
-            if (isInitialSyncing) {
+                  child: _BodyView(),
-              return const _InitialSyncBody();
+                )
-            } else {
+              : PopScope(
-              return Shimmer(
+                  canPop: false,
-                linearGradient: Theme.of(context).photoGridShimmerGradient,
+                  onPopInvoked: (_) {
-                child: const _Body(),
+                    context.addEvent(const _SetSelectedItems(items: {}));
-              );
+                  },
-            }
+                  child: const _BodyView(),
-          },
+                ),
         ),
       ),
     );
-    if (getRawPlatform() == NpPlatform.android) {
-      return WillPopScope(
-        onWillPop: () => _onBackButtonPressed(context),
-        child: content,
-      );
-    } else {
-      return content;
-    }
   }
 
-  Future<bool> _onBackButtonPressed(BuildContext context) async {
-    if (context.state.selectedItems.isEmpty) {
-      return DoubleTapExitHandler()();
-    } else {
-      context.addEvent(const _SetSelectedItems(items: {}));
-      return false;
-    }
-  }
-
-  late final _bloc = context.bloc;
-
   final _key = GlobalKey();
   bool? _isVisible;
 }
 
+class _BodyView extends StatelessWidget {
+  const _BodyView();
+
+  @override
+  Widget build(BuildContext context) {
+    return _BlocSelector<bool>(
+      selector: (state) => state.files.isEmpty && state.syncProgress != null,
+      builder: (context, isInitialSyncing) {
+        if (isInitialSyncing) {
+          return const _InitialSyncBody();
+        } else {
+          return Shimmer(
+            linearGradient: Theme.of(context).photoGridShimmerGradient,
+            child: const _Body(),
+          );
+        }
+      },
+    );
+  }
+}
+
 class _InitialSyncBody extends StatelessWidget {
   const _InitialSyncBody();
 
@@ -521,7 +522,7 @@ typedef _BlocSelector<T> = BlocSelector<_Bloc, _State, T>;
 
 extension on BuildContext {
   _Bloc get bloc => read<_Bloc>();
-  _State get state => bloc.state;
+  // _State get state => bloc.state;
   void addEvent(_Event event) => bloc.add(event);
 }