Refactoring

lib/widget/album_viewer.dart

@@ -156,7 +156,9 @@ class _AlbumViewerState extends State<AlbumViewer>
                 ignoring: isEditMode,
                 sliver: SliverOpacity(
                   opacity: isEditMode ? .25 : 1,
-                  sliver: buildItemStreamList(context),
+                  sliver: buildItemStreamList(
+                    maxCrossAxisExtent: thumbSize.toDouble(),
+                  ),
                 ),
               ),
             ),

lib/widget/album_viewer_mixin.dart

@@ -179,9 +179,6 @@ mixin AlbumViewerMixin<T extends StatefulWidget>
     );
   }
 
-  @override
-  get itemStreamListCellSize => thumbSize;
-
   @protected
   get isEditMode => _isEditMode;
 

lib/widget/archive_viewer.dart

@@ -73,9 +73,6 @@ class _ArchiveViewerState extends State<ArchiveViewer>
     );
   }
 
-  @override
-  get itemStreamListCellSize => _thumbSize;
-
   void _initBloc() {
     _bloc = ScanDirBloc.of(widget.account);
     if (_bloc.state is ScanDirBlocInit) {
@@ -105,7 +102,9 @@ class _ArchiveViewerState extends State<ArchiveViewer>
                 _buildAppBar(context),
                 SliverPadding(
                   padding: const EdgeInsets.all(16),
-                  sliver: buildItemStreamList(context),
+                  sliver: buildItemStreamList(
+                    maxCrossAxisExtent: _thumbSize.toDouble(),
+                  ),
                 ),
               ],
             ),

lib/widget/dynamic_album_viewer.dart

@@ -180,7 +180,9 @@ class _DynamicAlbumViewerState extends State<DynamicAlbumViewer>
                 ignoring: isEditMode,
                 sliver: SliverOpacity(
                   opacity: isEditMode ? .25 : 1,
-                  sliver: buildItemStreamList(context),
+                  sliver: buildItemStreamList(
+                    maxCrossAxisExtent: thumbSize.toDouble(),
+                  ),
                 ),
               ),
             ),

lib/widget/home_photos.dart

@@ -69,14 +69,6 @@ class _HomePhotosState extends State<HomePhotos>
     );
   }
 
-  @override
-  void onMaxExtentChanged(double maxExtent) {
-    setState(() {});
-  }
-
-  @override
-  int get itemStreamListCellSize => _thumbSize;
-
   void _initBloc() {
     _bloc = ScanDirBloc.of(widget.account);
     if (_bloc.state is ScanDirBlocInit) {
@@ -115,7 +107,14 @@ class _HomePhotosState extends State<HomePhotos>
                       _buildAppBar(context),
                       SliverPadding(
                         padding: const EdgeInsets.symmetric(vertical: 8),
-                        sliver: buildItemStreamList(context),
+                        sliver: buildItemStreamList(
+                          maxCrossAxisExtent: _thumbSize.toDouble(),
+                          onMaxExtentChanged: (value) {
+                            setState(() {
+                              _itemListMaxExtent = value;
+                            });
+                          },
+                        ),
                       ),
                     ],
                   ),
@@ -517,14 +516,14 @@ class _HomePhotosState extends State<HomePhotos>
 
   /// Return the estimated scroll extent of the custom scroll view, or null
   double _getScrollViewExtent(BoxConstraints constraints) {
-    if (calculatedMaxExtent != null &&
+    if (_itemListMaxExtent != null &&
         constraints.hasBoundedHeight &&
         _appBarExtent != null) {
       // scroll extent = list height - widget viewport height + sliver app bar height
       final scrollExtent =
-          calculatedMaxExtent - constraints.maxHeight + _appBarExtent;
+          _itemListMaxExtent - constraints.maxHeight + _appBarExtent;
       _log.info(
-          "[_getScrollViewExtent] $calculatedMaxExtent - ${constraints.maxHeight} + $_appBarExtent = $scrollExtent");
+          "[_getScrollViewExtent] $_itemListMaxExtent - ${constraints.maxHeight} + $_appBarExtent = $scrollExtent");
       return scrollExtent;
     } else {
       return null;
@@ -574,6 +573,7 @@ class _HomePhotosState extends State<HomePhotos>
   final ScrollController _scrollController = ScrollController();
 
   double _appBarExtent;
+  double _itemListMaxExtent;
 
   static final _log = Logger("widget.home_photos._HomePhotosState");
   static const _menuValueRefresh = 0;

lib/widget/selectable_item_stream_list_mixin.dart

@@ -55,23 +55,20 @@ mixin SelectableItemStreamListMixin<T extends StatefulWidget> on State<T> {
   }
 
   @protected
-  Widget buildItemStreamList(BuildContext context) {
+  Widget buildItemStreamList({
+    @required double maxCrossAxisExtent,
+    ValueChanged<double> onMaxExtentChanged,
+  }) {
     return MeasurableItemList(
       key: _listKey,
-      maxCrossAxisExtent: itemStreamListCellSize.toDouble(),
+      maxCrossAxisExtent: maxCrossAxisExtent,
       itemCount: _items.length,
       itemBuilder: _buildItem,
       staggeredTileBuilder: (index) => _items[index].staggeredTile,
-      onMaxExtentChanged: (newExtent) {
+      onMaxExtentChanged: onMaxExtentChanged,
-        _calculatedMaxExtent = newExtent;
-        onMaxExtentChanged(newExtent);
-      },
     );
   }
 
-  @protected
-  void onMaxExtentChanged(double newExtent) {}
-
   @protected
   void clearSelectedItems() {
     _selectedItems.clear();
@@ -113,12 +110,6 @@ mixin SelectableItemStreamListMixin<T extends StatefulWidget> on State<T> {
         (_listKey.currentState as MeasurableItemListState)?.updateListHeight());
   }
 
-  @protected
-  int get itemStreamListCellSize;
-
-  @protected
-  double get calculatedMaxExtent => _calculatedMaxExtent;
-
   Widget _buildItem(BuildContext context, int index) {
     final item = _items[index];
     final content = Padding(
@@ -237,7 +228,6 @@ mixin SelectableItemStreamListMixin<T extends StatefulWidget> on State<T> {
   final _selectedItems = <SelectableItemStreamListItem>{};
 
   final _listKey = GlobalKey();
-  double _calculatedMaxExtent;
 
   /// used to gain focus on web for keyboard support
   final _keyboardFocus = FocusNode();