fullscreen: modified widget rebuild logic

lib/widgets/fullscreen/fullscreen_body.dart

@@ -38,7 +38,7 @@ class FullscreenBody extends StatefulWidget {
 }
 
 class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProviderStateMixin, WidgetsBindingObserver {
-  ImageEntry _entry;
+  final ValueNotifier<ImageEntry> _entryNotifier = ValueNotifier(null);
   int _currentHorizontalPage;
   ValueNotifier<int> _currentVerticalPage;
   PageController _horizontalPager, _verticalPager;
@@ -57,19 +57,18 @@ class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProvide
 
   List<ImageEntry> get entries => hasCollection ? collection.sortedEntries : [widget.initialEntry];
 
-  List<String> get pages => ['transition', 'image', 'info'];
+  static const int transitionPage = 0;
 
-  int get transitionPage => pages.indexOf('transition');
+  static const int imagePage = 1;
 
-  int get imagePage => pages.indexOf('image');
+  static const int infoPage = 2;
-
-  int get infoPage => pages.indexOf('info');
 
   @override
   void initState() {
     super.initState();
-    _entry = widget.initialEntry;
+    final entry = widget.initialEntry;
-    _currentHorizontalPage = max(0, entries.indexOf(_entry));
+    _entryNotifier.value = entry;
+    _currentHorizontalPage = max(0, entries.indexOf(entry));
     _currentVerticalPage = ValueNotifier(imagePage);
     _horizontalPager = PageController(initialPage: _currentHorizontalPage);
     _verticalPager = PageController(initialPage: _currentVerticalPage.value)..addListener(_onVerticalPageControllerChange);
@@ -138,76 +137,6 @@ class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProvide
 
   @override
   Widget build(BuildContext context) {
-    final topOverlay = ValueListenableBuilder<int>(
-      valueListenable: _currentVerticalPage,
-      builder: (context, page, child) {
-        final showOverlay = _entry != null && page == imagePage;
-        return showOverlay
-            ? FullscreenTopOverlay(
-                entries: entries,
-                index: _currentHorizontalPage,
-                scale: _topOverlayScale,
-                canToggleFavourite: hasCollection,
-                viewInsets: _frozenViewInsets,
-                viewPadding: _frozenViewPadding,
-                onActionSelected: (action) => _actionDelegate.onActionSelected(context, _entry, action),
-              )
-            : const SizedBox.shrink();
-      },
-    );
-
-    final videoController = _entry != null && _entry.isVideo ? _videoControllers.firstWhere((kv) => kv.item1 == _entry.uri, orElse: () => null)?.item2 : null;
-    Widget bottomOverlay = Column(
-      children: [
-        if (videoController != null)
-          VideoControlOverlay(
-            entry: _entry,
-            controller: videoController,
-            scale: _bottomOverlayScale,
-            viewInsets: _frozenViewInsets,
-            viewPadding: _frozenViewPadding,
-          ),
-        SlideTransition(
-          position: _bottomOverlayOffset,
-          child: FullscreenBottomOverlay(
-            entries: entries,
-            index: _currentHorizontalPage,
-            showPosition: hasCollection,
-            viewInsets: _frozenViewInsets,
-            viewPadding: _frozenViewPadding,
-          ),
-        ),
-      ],
-    );
-    bottomOverlay = ValueListenableBuilder<double>(
-      valueListenable: _overlayAnimationController,
-      builder: (context, animation, child) {
-        return Visibility(
-          visible: _entry != null && _overlayAnimationController.status != AnimationStatus.dismissed,
-          child: child,
-        );
-      },
-      child: bottomOverlay,
-    );
-
-    bottomOverlay = Selector<MediaQueryData, double>(
-      selector: (c, mq) => mq.size.height,
-      builder: (c, mqHeight, child) {
-        // when orientation change, the `PageController` offset is not updated right away
-        // and it does not trigger its listeners when it does, so we force a refresh in the next frame
-        WidgetsBinding.instance.addPostFrameCallback((_) => _onVerticalPageControllerChange());
-        return AnimatedBuilder(
-          animation: _verticalScrollNotifier,
-          builder: (context, child) => Positioned(
-            bottom: (_verticalPager.offset ?? 0) - mqHeight,
-            child: child,
-          ),
-          child: child,
-        );
-      },
-      child: bottomOverlay,
-    );
-
     return WillPopScope(
       onWillPop: () {
         if (_currentVerticalPage.value == infoPage) {
@@ -227,7 +156,7 @@ class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProvide
           children: [
             FullscreenVerticalPageView(
               collection: collection,
-              entry: _entry,
+              entryNotifier: _entryNotifier,
               videoControllers: _videoControllers,
               verticalPager: _verticalPager,
               horizontalPager: _horizontalPager,
@@ -236,14 +165,106 @@ class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProvide
               onImageTap: () => _overlayVisible.value = !_overlayVisible.value,
               onImagePageRequested: () => _goToVerticalPage(imagePage),
             ),
-            topOverlay,
+            _buildTopOverlay(),
-            bottomOverlay,
+            _buildBottomOverlay(),
           ],
         ),
       ),
     );
   }
 
+  Widget _buildTopOverlay() {
+    final child = ValueListenableBuilder<ImageEntry>(
+      valueListenable: _entryNotifier,
+      builder: (context, entry, child) {
+        if (entry == null) return const SizedBox.shrink();
+        return FullscreenTopOverlay(
+          entry: entry,
+          scale: _topOverlayScale,
+          canToggleFavourite: hasCollection,
+          viewInsets: _frozenViewInsets,
+          viewPadding: _frozenViewPadding,
+          onActionSelected: (action) => _actionDelegate.onActionSelected(context, entry, action),
+        );
+      },
+    );
+    return ValueListenableBuilder<int>(
+      valueListenable: _currentVerticalPage,
+      builder: (context, page, child) {
+        return Visibility(
+          visible: page == imagePage,
+          child: child,
+        );
+      },
+      child: child,
+    );
+  }
+
+  Widget _buildBottomOverlay() {
+    Widget bottomOverlay = ValueListenableBuilder<ImageEntry>(
+      valueListenable: _entryNotifier,
+      builder: (context, entry, child) {
+        Widget videoOverlay;
+        if (entry != null) {
+          final videoController = entry.isVideo ? _videoControllers.firstWhere((kv) => kv.item1 == entry.uri, orElse: () => null)?.item2 : null;
+          if (videoController != null) {
+            videoOverlay = VideoControlOverlay(
+              entry: entry,
+              controller: videoController,
+              scale: _bottomOverlayScale,
+              viewInsets: _frozenViewInsets,
+              viewPadding: _frozenViewPadding,
+            );
+          }
+        }
+        final child = Column(
+          children: [
+            if (videoOverlay != null) videoOverlay,
+            SlideTransition(
+              position: _bottomOverlayOffset,
+              child: FullscreenBottomOverlay(
+                entries: entries,
+                index: _currentHorizontalPage,
+                showPosition: hasCollection,
+                viewInsets: _frozenViewInsets,
+                viewPadding: _frozenViewPadding,
+              ),
+            ),
+          ],
+        );
+        return ValueListenableBuilder<double>(
+          valueListenable: _overlayAnimationController,
+          builder: (context, animation, child) {
+            return Visibility(
+              visible: entry != null && _overlayAnimationController.status != AnimationStatus.dismissed,
+              child: child,
+            );
+          },
+          child: child,
+        );
+      },
+    );
+
+    bottomOverlay = Selector<MediaQueryData, double>(
+      selector: (c, mq) => mq.size.height,
+      builder: (c, mqHeight, child) {
+        // when orientation change, the `PageController` offset is not updated right away
+        // and it does not trigger its listeners when it does, so we force a refresh in the next frame
+        WidgetsBinding.instance.addPostFrameCallback((_) => _onVerticalPageControllerChange());
+        return AnimatedBuilder(
+          animation: _verticalScrollNotifier,
+          builder: (context, child) => Positioned(
+            bottom: (_verticalPager.offset ?? 0) - mqHeight,
+            child: child,
+          ),
+          child: child,
+        );
+      },
+      child: bottomOverlay,
+    );
+    return bottomOverlay;
+  }
+
   void _onVerticalPageControllerChange() {
     _verticalScrollNotifier.notifyListeners();
   }
@@ -286,11 +307,10 @@ class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProvide
 
   void _updateEntry() {
     final newEntry = _currentHorizontalPage != null && _currentHorizontalPage < entries.length ? entries[_currentHorizontalPage] : null;
-    if (_entry == newEntry) return;
+    if (_entryNotifier.value == newEntry) return;
-    _entry = newEntry;
+    _entryNotifier.value = newEntry;
     _pauseVideoControllers();
     _initVideoController();
-    setState(() {});
   }
 
   void _onLeave() {
@@ -301,13 +321,13 @@ class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProvide
     _showSystemUI();
   }
 
-  // system UI
+// system UI
 
   static void _showSystemUI() => SystemChrome.setEnabledSystemUIOverlays(SystemUiOverlay.values);
 
   static void _hideSystemUI() => SystemChrome.setEnabledSystemUIOverlays([]);
 
-  // overlay
+// overlay
 
   Future<void> _initOverlay() async {
     // wait for MaterialPageRoute.transitionDuration
@@ -348,9 +368,10 @@ class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProvide
   void _pauseVideoControllers() => _videoControllers.forEach((e) => e.item2.pause());
 
   Future<void> _initVideoController() async {
-    if (_entry == null || !_entry.isVideo) return;
+    final entry = _entryNotifier.value;
+    if (entry == null || !entry.isVideo) return;
 
-    final uri = _entry.uri;
+    final uri = entry.uri;
     var controllerEntry = _videoControllers.firstWhere((kv) => kv.item1 == uri, orElse: () => null);
     if (controllerEntry != null) {
       _videoControllers.remove(controllerEntry);
@@ -362,12 +383,13 @@ class FullscreenBodyState extends State<FullscreenBody> with SingleTickerProvide
     while (_videoControllers.length > 3) {
       _videoControllers.removeLast().item2.dispose();
     }
+    setState(() {});
   }
 }
 
 class FullscreenVerticalPageView extends StatefulWidget {
   final CollectionLens collection;
-  final ImageEntry entry;
+  final ValueNotifier<ImageEntry> entryNotifier;
   final List<Tuple2<String, IjkMediaController>> videoControllers;
   final PageController horizontalPager, verticalPager;
   final void Function(int page) onVerticalPageChanged, onHorizontalPageChanged;
@@ -375,7 +397,7 @@ class FullscreenVerticalPageView extends StatefulWidget {
 
   const FullscreenVerticalPageView({
     @required this.collection,
-    @required this.entry,
+    @required this.entryNotifier,
     @required this.videoControllers,
     @required this.verticalPager,
     @required this.horizontalPager,
@@ -392,12 +414,13 @@ class FullscreenVerticalPageView extends StatefulWidget {
 class _FullscreenVerticalPageViewState extends State<FullscreenVerticalPageView> {
   final ValueNotifier<Color> _backgroundColorNotifier = ValueNotifier(Colors.black);
   final ValueNotifier<bool> _infoPageVisibleNotifier = ValueNotifier(false);
+  ImageEntry _oldEntry;
 
   CollectionLens get collection => widget.collection;
 
   bool get hasCollection => collection != null;
 
-  ImageEntry get entry => widget.entry;
+  ImageEntry get entry => widget.entryNotifier.value;
 
   @override
   void initState() {
@@ -420,12 +443,12 @@ class _FullscreenVerticalPageViewState extends State<FullscreenVerticalPageView>
 
   void _registerWidget(FullscreenVerticalPageView widget) {
     widget.verticalPager.addListener(_onVerticalPageControllerChanged);
-    widget.entry?.imageChangeNotifier?.addListener(_onImageChanged);
+    widget.entryNotifier.addListener(_onEntryChanged);
   }
 
   void _unregisterWidget(FullscreenVerticalPageView widget) {
     widget.verticalPager.removeListener(_onVerticalPageControllerChanged);
-    widget.entry?.imageChangeNotifier?.removeListener(_onImageChanged);
+    widget.entryNotifier.removeListener(_onEntryChanged);
   }
 
   @override
@@ -453,7 +476,7 @@ class _FullscreenVerticalPageViewState extends State<FullscreenVerticalPageView>
         },
         child: InfoPage(
           collection: collection,
-          entry: entry,
+          entryNotifier: widget.entryNotifier,
           visibleNotifier: _infoPageVisibleNotifier,
         ),
       ),
@@ -482,6 +505,14 @@ class _FullscreenVerticalPageViewState extends State<FullscreenVerticalPageView>
     _backgroundColorNotifier.value = _backgroundColorNotifier.value.withOpacity(opacity * opacity);
   }
 
+  // when the entry changed (e.g. by scrolling through the PageView, or if the entry got deleted)
+  void _onEntryChanged() {
+    _oldEntry?.imageChangeNotifier?.removeListener(_onImageChanged);
+    entry?.imageChangeNotifier?.addListener(_onImageChanged);
+    _oldEntry = entry;
+  }
+
+  // when the entry image itself changed (e.g. after rotation)
   void _onImageChanged() async {
     await UriImage(uri: entry.uri, mimeType: entry.mimeType).evict();
     // TODO TLAD also evict `ThumbnailProvider` with specified extents

lib/widgets/fullscreen/info/info_page.dart

@@ -14,14 +14,14 @@ import 'package:tuple/tuple.dart';
 
 class InfoPage extends StatefulWidget {
   final CollectionLens collection;
-  final ImageEntry entry;
+  final ValueNotifier<ImageEntry> entryNotifier;
   final ValueNotifier<bool> visibleNotifier;
 
   const InfoPage({
     Key key,
     @required this.collection,
-    @required this.entry,
+    @required this.entryNotifier,
-    this.visibleNotifier,
+    @required this.visibleNotifier,
   }) : super(key: key);
 
   @override
@@ -34,12 +34,31 @@ class InfoPageState extends State<InfoPage> {
 
   CollectionLens get collection => widget.collection;
 
-  ImageEntry get entry => widget.entry;
-
   @override
   void initState() {
     super.initState();
-    entry.locate();
+    _registerWidget(widget);
+  }
+
+  @override
+  void didUpdateWidget(InfoPage oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    _unregisterWidget(oldWidget);
+    _registerWidget(widget);
+  }
+
+  @override
+  void dispose() {
+    _unregisterWidget(widget);
+    super.dispose();
+  }
+
+  void _registerWidget(InfoPage widget) {
+    widget.entryNotifier.addListener(_onEntryChanged);
+  }
+
+  void _unregisterWidget(InfoPage widget) {
+    widget.entryNotifier.removeListener(_onEntryChanged);
   }
 
   @override
@@ -67,8 +86,11 @@ class InfoPageState extends State<InfoPage> {
                 final mqWidth = mq.item1;
                 final mqViewInsetsBottom = mq.item2;
                 final split = mqWidth > 400;
-                final locationAtTop = split && entry.hasGps;
 
+                return ValueListenableBuilder(
+                  valueListenable: widget.entryNotifier,
+                  builder: (context, entry, child) {
+                    final locationAtTop = split && entry.hasGps;
                     final locationSection = LocationSection(
                       collection: collection,
                       entry: entry,
@@ -115,6 +137,8 @@ class InfoPageState extends State<InfoPage> {
                       ],
                     );
                   },
+                );
+              },
             ),
           ),
         ),
@@ -123,6 +147,10 @@ class InfoPageState extends State<InfoPage> {
     );
   }
 
+  void _onEntryChanged() {
+    widget.entryNotifier.value?.locate();
+  }
+
   bool _handleTopScroll(Notification notification) {
     if (notification is ScrollNotification) {
       if (notification is ScrollStartNotification) {

lib/widgets/fullscreen/overlay/top.dart

@@ -9,17 +9,15 @@ import 'package:aves/widgets/fullscreen/overlay/common.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
+import 'package:tuple/tuple.dart';
 
 class FullscreenTopOverlay extends StatelessWidget {
-  final List<ImageEntry> entries;
+  final ImageEntry entry;
-  final int index;
   final Animation<double> scale;
   final EdgeInsets viewInsets, viewPadding;
   final Function(EntryAction value) onActionSelected;
   final bool canToggleFavourite;
 
-  ImageEntry get entry => entries[index];
-
   static const double padding = 8;
 
   static const int landscapeActionCount = 3;
@@ -28,13 +26,12 @@ class FullscreenTopOverlay extends StatelessWidget {
 
   const FullscreenTopOverlay({
     Key key,
-    @required this.entries,
+    @required this.entry,
-    @required this.index,
     @required this.scale,
-    this.canToggleFavourite = false,
+    @required this.canToggleFavourite,
-    this.viewInsets,
+    @required this.viewInsets,
-    this.viewPadding,
+    @required this.viewPadding,
-    this.onActionSelected,
+    @required this.onActionSelected,
   }) : super(key: key);
 
   @override
@@ -43,49 +40,31 @@ class FullscreenTopOverlay extends StatelessWidget {
       minimum: (viewInsets ?? EdgeInsets.zero) + (viewPadding ?? EdgeInsets.zero),
       child: Padding(
         padding: const EdgeInsets.all(padding),
-        child: Selector<MediaQueryData, Orientation>(
+        child: Selector<MediaQueryData, Tuple2<double, Orientation>>(
-          selector: (c, mq) => mq.orientation,
+          selector: (c, mq) => Tuple2(mq.size.width, mq.orientation),
-          builder: (c, orientation, child) {
+          builder: (c, mq, child) {
-            final targetCount = orientation == Orientation.landscape ? landscapeActionCount : portraitActionCount;
+            final mqWidth = mq.item1;
-            return LayoutBuilder(
+            final mqOrientation = mq.item2;
-              builder: (context, constraints) {
+
-                final availableCount = (constraints.maxWidth / (kMinInteractiveDimension + padding)).floor() - 2;
+            final targetCount = mqOrientation == Orientation.landscape ? landscapeActionCount : portraitActionCount;
+            final availableCount = (mqWidth / (kMinInteractiveDimension + padding)).floor() - 2;
             final quickActionCount = min(targetCount, availableCount);
 
             final quickActions = [
               EntryAction.toggleFavourite,
               EntryAction.share,
               EntryAction.delete,
-                ].where(_canDo).take(quickActionCount);
+            ].where(_canDo).take(quickActionCount).toList();
-                final inAppActions = EntryActions.inApp.where((action) => !quickActions.contains(action)).where(_canDo);
+            final inAppActions = EntryActions.inApp.where((action) => !quickActions.contains(action)).where(_canDo).toList();
-                final externalAppActions = EntryActions.externalApp.where(_canDo);
+            final externalAppActions = EntryActions.externalApp.where(_canDo).toList();
 
-                return Row(
+            return _TopOverlayRow(
-                  children: [
+              quickActions: quickActions,
-                    OverlayButton(
+              inAppActions: inAppActions,
+              externalAppActions: externalAppActions,
               scale: scale,
-                      child: ModalRoute.of(context)?.canPop ?? true ? const BackButton() : const CloseButton(),
+              isFavouriteNotifier: entry.isFavouriteNotifier,
-                    ),
+              onActionSelected: onActionSelected,
-                    const Spacer(),
-                    ...quickActions.map(_buildOverlayButton),
-                    OverlayButton(
-                      scale: scale,
-                      child: PopupMenuButton<EntryAction>(
-                        itemBuilder: (context) => [
-                          ...inAppActions.map(_buildPopupMenuItem),
-                          const PopupMenuDivider(),
-                          ...externalAppActions.map(_buildPopupMenuItem),
-                          if (kDebugMode) ...[
-                            const PopupMenuDivider(),
-                            _buildPopupMenuItem(EntryAction.debug),
-                          ]
-                        ],
-                        onSelected: onActionSelected,
-                      ),
-                    ),
-                  ],
-                );
-              },
             );
           },
         ),
@@ -118,6 +97,56 @@ class FullscreenTopOverlay extends StatelessWidget {
     }
     return false;
   }
+}
+
+class _TopOverlayRow extends StatelessWidget {
+  final List<EntryAction> quickActions;
+  final List<EntryAction> inAppActions;
+  final List<EntryAction> externalAppActions;
+  final Animation<double> scale;
+  final ValueNotifier<bool> isFavouriteNotifier;
+  final Function(EntryAction value) onActionSelected;
+
+  const _TopOverlayRow({
+    Key key,
+    @required this.quickActions,
+    @required this.inAppActions,
+    @required this.externalAppActions,
+    @required this.scale,
+    @required this.isFavouriteNotifier,
+    @required this.onActionSelected,
+  }) : super(key: key);
+
+  static const double padding = 8;
+
+  @override
+  Widget build(BuildContext context) {
+    return Row(
+      children: [
+        OverlayButton(
+          scale: scale,
+          child: ModalRoute.of(context)?.canPop ?? true ? const BackButton() : const CloseButton(),
+        ),
+        const Spacer(),
+        ...quickActions.map(_buildOverlayButton),
+        OverlayButton(
+          scale: scale,
+          child: PopupMenuButton<EntryAction>(
+            itemBuilder: (context) => [
+              ...inAppActions.map(_buildPopupMenuItem),
+              const PopupMenuDivider(),
+              ...externalAppActions.map(_buildPopupMenuItem),
+              if (kDebugMode) ...[
+                const PopupMenuDivider(),
+                _buildPopupMenuItem(EntryAction.debug),
+              ]
+            ],
+            onSelected: onActionSelected,
+          ),
+        ),
+      ],
+    );
+  }
 
   Widget _buildOverlayButton(EntryAction action) {
     Widget child;
@@ -125,7 +154,7 @@ class FullscreenTopOverlay extends StatelessWidget {
     switch (action) {
       case EntryAction.toggleFavourite:
         child = ValueListenableBuilder<bool>(
-          valueListenable: entry.isFavouriteNotifier,
+          valueListenable: isFavouriteNotifier,
           builder: (context, isFavourite, child) => Stack(
             alignment: Alignment.center,
             children: [
@@ -136,7 +165,7 @@ class FullscreenTopOverlay extends StatelessWidget {
               ),
               Sweeper(
                 builder: (context) => const Icon(AIcons.favourite, color: Colors.redAccent),
-                toggledNotifier: entry.isFavouriteNotifier,
+                toggledNotifier: isFavouriteNotifier,
               ),
             ],
           ),
@@ -178,7 +207,7 @@ class FullscreenTopOverlay extends StatelessWidget {
     switch (action) {
       // in app actions
       case EntryAction.toggleFavourite:
-        child = entry.isFavouriteNotifier.value
+        child = isFavouriteNotifier.value
             ? const MenuRow(
                 text: 'Remove from favourites',
                 icon: AIcons.favouriteActive,