Fixed an issue where clicking on local comics on the home page would cause the history to be lost. Close #196

lib/foundation/history.dart

@@ -319,7 +319,7 @@ class HistoryManager with ChangeNotifier {
     for (var element in res) {
       _cachedHistoryIds![element["id"] as String] = true;
     }
-    for (var key in cachedHistories.keys) {
+    for (var key in cachedHistories.keys.toList()) {
       if (!_cachedHistoryIds!.containsKey(key)) {
         cachedHistories.remove(key);
       }

lib/pages/comic_details_page/comic_page.dart

@@ -165,6 +165,8 @@ class _ComicPageState extends LoadingState<ComicPage, ComicDetails>
               cid: widget.id,
               name: localComic.title,
               chapters: localComic.chapters,
+              initialPage: history?.page,
+              initialChapter: history?.ep,
               history: history ??
                   History.fromModel(
                     model: localComic,

lib/pages/reader/images.dart

@@ -406,6 +406,9 @@ class _ContinuousModeState extends State<_ContinuousMode>
   }
 
   void onPositionChanged() {
+    if (itemPositionsListener.itemPositions.value.isEmpty) {
+      return;
+    }
     var page = itemPositionsListener.itemPositions.value.first.index;
     page = page.clamp(1, reader.maxPage);
     if (page != reader.page) {