Add a setting for long press position. Close #287

lib/components/layout.dart

@@ -163,3 +163,29 @@ class SliverLazyToBoxAdapter extends StatelessWidget {
     ]);
   }
 }
+
+class SliverAnimatedVisibility extends StatelessWidget {
+  const SliverAnimatedVisibility({
+    super.key,
+    required this.visible,
+    required this.child,
+  });
+
+  final bool visible;
+
+  final Widget child;
+
+  @override
+  Widget build(BuildContext context) {
+    var child = visible ? this.child : const SizedBox.shrink();
+
+    return SliverToBoxAdapter(
+      child: AnimatedSize(
+        duration: const Duration(milliseconds: 200),
+        curve: Curves.easeInOut,
+        alignment: Alignment.topCenter,
+        child: child,
+      ),
+    );
+  }
+}

lib/foundation/appdata.dart

@@ -161,6 +161,7 @@ class Settings with ChangeNotifier {
     'cacheSize': 2048, // in MB
     'downloadThreads': 5,
     'enableLongPressToZoom': true,
+    'longPressZoomPosition': "press", // press, center
     'checkUpdateOnStart': false,
     'limitImageWidth': true,
     'webdav': [], // empty means not configured

lib/pages/reader/images.dart

@@ -343,10 +343,19 @@ class _GalleryModeState extends State<_GalleryMode>
     }
     var photoViewController = photoViewControllers[reader.page]!;
     double target = photoViewController.getInitialScale!.call()! * 1.75;
-    var size = MediaQuery.of(context).size;
+    var size = reader.size;
+    Offset zoomPosition;
+    if (appdata.settings['longPressZoomPosition'] != 'center') {
+      zoomPosition = Offset(
+        size.width / 2 - location.dx,
+        size.height / 2 - location.dy,
+      );
+    } else {
+      zoomPosition = Offset(0, 0);
+    }
     photoViewController.animateScale?.call(
       target,
-      Offset(size.width / 2 - location.dx, size.height / 2 - location.dy),
+      zoomPosition,
     );
     isLongPressing = true;
   }
@@ -608,6 +617,13 @@ class _ContinuousModeState extends State<_ContinuousMode>
   }
 
   bool onScaleUpdate([double? scale]) {
+    if (prepareToNextChapter || prepareToPrevChapter) {
+      setState(() {
+        prepareToPrevChapter = false;
+        prepareToNextChapter = false;
+      });
+      context.readerScaffold.setFloatingButton(0);
+    }
     var isZoomedIn = (scale ?? photoViewController.scale) != 1.0;
     if (isZoomedIn != this.isZoomedIn) {
       setState(() {
@@ -731,7 +747,7 @@ class _ContinuousModeState extends State<_ContinuousMode>
         }
         Offset offset;
         var sp = scrollController.position;
-        if (sp.pixels < sp.minScrollExtent || sp.pixels > sp.maxScrollExtent) {
+        if (sp.pixels <= sp.minScrollExtent || sp.pixels >= sp.maxScrollExtent) {
           offset = Offset(value.dx, value.dy);
         } else {
           if (reader.mode == ReaderMode.continuousTopToBottom) {
@@ -759,7 +775,10 @@ class _ContinuousModeState extends State<_ContinuousMode>
           delayedSetIsScrolling(false);
         }
 
-        if (notification is ScrollUpdateNotification) {
+        var scale = photoViewController.scale ?? 1.0;
+
+        if (notification is ScrollUpdateNotification &&
+            (scale - 1).abs() < 0.05) {
           if (!scrollController.hasClients) return false;
           if (scrollController.position.pixels <=
                   scrollController.position.minScrollExtent &&
@@ -800,8 +819,8 @@ class _ContinuousModeState extends State<_ContinuousMode>
       },
       child: widget,
     );
-    var width = MediaQuery.of(context).size.width;
-    var height = MediaQuery.of(context).size.height;
+    var width = reader.size.width;
+    var height = reader.size.height;
     if (appdata.settings['limitImageWidth'] &&
         width / height > 0.7 &&
         reader.mode == ReaderMode.continuousTopToBottom) {
@@ -882,9 +901,19 @@ class _ContinuousModeState extends State<_ContinuousMode>
       return;
     }
     double target = photoViewController.getInitialScale!.call()! * 1.75;
+    var size = reader.size;
+    Offset zoomPosition;
+    if (appdata.settings['longPressZoomPosition'] != 'center') {
+      zoomPosition = Offset(
+        size.width / 2 - location.dx,
+        size.height / 2 - location.dy,
+      );
+    } else {
+      zoomPosition = Offset(0, 0);
+    }
     photoViewController.animateScale?.call(
       target,
-      Offset(0, 0),
+      zoomPosition,
     );
     onScaleUpdate(target);
     isLongPressing = true;

lib/pages/reader/reader.dart

@@ -309,6 +309,13 @@ class _ReaderState extends State<Reader>
     }
     return chapter == maxChapter;
   }
+
+  /// Get the size of the reader.
+  /// The size is not always the same as the size of the screen.
+  Size get size {
+    var renderBox = context.findRenderObject() as RenderBox;
+    return renderBox.size;
+  }
 }
 
 abstract mixin class _ImagePerPageHandler {

lib/pages/settings/reader.dart

@@ -48,6 +48,7 @@ class _ReaderSettingsState extends State<ReaderSettings> {
             "continuousTopToBottom": "Continuous (Top to Bottom)".tl,
           },
           onChanged: () {
+            setState(() {});
             var readerMode = appdata.settings['readerMode'];
             if (readerMode?.toLowerCase().startsWith('continuous') ?? false) {
               appdata.settings['readerScreenPicNumberForLandscape'] = 1;
@@ -68,67 +69,55 @@ class _ReaderSettingsState extends State<ReaderSettings> {
             widget.onChanged?.call("autoPageTurningInterval");
           },
         ).toSliver(),
-        SliverToBoxAdapter(
-          child: AbsorbPointer(
-            absorbing: (appdata.settings['readerMode']
-                    ?.toLowerCase()
-                    .startsWith('continuous') ??
-                false),
-            child: AnimatedOpacity(
-              opacity: (appdata.settings['readerMode']
-                          ?.toLowerCase()
-                          .startsWith('continuous') ??
-                      false)
-                  ? 0.5
-                  : 1.0,
-              duration: Duration(milliseconds: 300),
-              child: _SliderSetting(
-                title: "The number of pic in screen for landscape (Only Gallery Mode)".tl,
-                settingsIndex: "readerScreenPicNumberForLandscape",
-                interval: 1,
-                min: 1,
-                max: 5,
-                onChanged: () {
-                  widget.onChanged?.call("readerScreenPicNumberForLandscape");
-                },
-              ),
-            ),
+        SliverAnimatedVisibility(
+          visible: appdata.settings['readerMode']!.startsWith('gallery'),
+          child: _SliderSetting(
+            title:
+                "The number of pic in screen for landscape (Only Gallery Mode)"
+                    .tl,
+            settingsIndex: "readerScreenPicNumberForLandscape",
+            interval: 1,
+            min: 1,
+            max: 5,
+            onChanged: () {
+              widget.onChanged?.call("readerScreenPicNumberForLandscape");
+            },
           ),
         ),
-        SliverToBoxAdapter(
-          child: AbsorbPointer(
-            absorbing: (appdata.settings['readerMode']
-                ?.toLowerCase()
-                .startsWith('continuous') ??
-                false),
-            child: AnimatedOpacity(
-              opacity: (appdata.settings['readerMode']
-                  ?.toLowerCase()
-                  .startsWith('continuous') ??
-                  false)
-                  ? 0.5
-                  : 1.0,
-              duration: Duration(milliseconds: 300),
-              child: _SliderSetting(
-                title: "The number of pic in screen for portrait (Only Gallery Mode)".tl,
-                settingsIndex: "readerScreenPicNumberForPortrait",
-                interval: 1,
-                min: 1,
-                max: 5,
-                onChanged: () {
-                  widget.onChanged?.call("readerScreenPicNumberForPortrait");
-                },
-              ),
-            ),
+        SliverAnimatedVisibility(
+          visible: appdata.settings['readerMode']!.startsWith('gallery'),
+          child: _SliderSetting(
+            title:
+                "The number of pic in screen for portrait (Only Gallery Mode)"
+                    .tl,
+            settingsIndex: "readerScreenPicNumberForPortrait",
+            interval: 1,
+            min: 1,
+            max: 5,
+            onChanged: () {
+              widget.onChanged?.call("readerScreenPicNumberForPortrait");
+            },
           ),
         ),
         _SwitchSetting(
           title: 'Long press to zoom'.tl,
           settingKey: 'enableLongPressToZoom',
           onChanged: () {
+            setState(() {});
             widget.onChanged?.call('enableLongPressToZoom');
           },
         ).toSliver(),
+        SliverAnimatedVisibility(
+          visible: appdata.settings['enableLongPressToZoom'] == true,
+          child: SelectSetting(
+            title: "Long press zoom position".tl,
+            settingKey: "longPressZoomPosition",
+            optionTranslation: {
+              "press": "Press position".tl,
+              "center": "Screen center".tl,
+            },
+          ),
+        ),
         _SwitchSetting(
           title: 'Limit image width'.tl,
           subtitle: 'When using Continuous(Top to Bottom) mode'.tl,