improve code

lib/components/navigation_bar.dart

@@ -127,13 +127,15 @@ class _NaviPaneState extends State<NaviPane>
       }
       if (target == 1) {
         StateController.find<NaviPaddingWidgetController>()
-            .setWithPadding(true);
+            .setWithPadding(true, true);
         controller.value = target;
       } else if (controller.value == 1 && target == 0) {
         StateController.findOrNull<NaviPaddingWidgetController>()
-            ?.setWithPadding(false);
+            ?.setWithPadding(false, false);
         controller.value = target;
       } else {
+        StateController.findOrNull<NaviPaddingWidgetController>()
+            ?.setWithPadding(true, false);
         controller.animateTo(target);
       }
       animationTarget = target;
@@ -181,14 +183,14 @@ class _NaviPaneState extends State<NaviPane>
               ),
               Positioned(
                 top: _kTopBarHeight * ((1 - value).clamp(0, 1)) +
-                    MediaQuery.of(context).padding.top * (value == 1 ? 0 : 1),
+                    MediaQuery.of(context).padding.top * (value == 0 ? 1 : 0),
                 left: _kFoldedSideBarWidth * ((value - 1).clamp(0, 1)) +
                     (_kSideBarWidth - _kFoldedSideBarWidth) *
                         ((value - 2).clamp(0, 1)),
                 right: 0,
                 bottom: bottomBarHeight * ((1 - value).clamp(0, 1)),
                 child: MediaQuery.removePadding(
-                  removeTop: value >= 2 || value == 0,
+                  removeTop: value == 0,
                   context: context,
                   child: Material(child: widget.pageBuilder(currentPage)),
                 ),
@@ -656,8 +658,11 @@ class NaviPaddingWidgetController extends StateController {
 
   bool _withPadding = false;
 
-  void setWithPadding(bool value) {
-    _withPadding = value;
+  bool _withTopBarPadding = false;
+
+  void setWithPadding(bool withPadding, bool withAppbarPadding) {
+    _withPadding = withPadding;
+    _withTopBarPadding = withAppbarPadding;
     update();
   }
 }
@@ -674,7 +679,10 @@ class NaviPaddingWidget extends StatelessWidget {
         return Padding(
           padding: controller._withPadding
               ? EdgeInsets.only(
-                  top: _NaviPaneState._kTopBarHeight + context.padding.top,
+                  top: context.padding.top +
+                      (controller._withTopBarPadding
+                          ? _NaviPaneState._kTopBarHeight
+                          : 0),
                   bottom:
                       _NaviPaneState._kBottomBarHeight + context.padding.bottom,
                 )

lib/foundation/appdata.dart

@@ -8,10 +8,20 @@ class _Appdata {
 
   var searchHistory = <String>[];
 
-  void saveData() async {
+  bool _isSavingData = false;
+  
+  Future<void> saveData() async {
+    if(_isSavingData) {
+      await Future.doWhile(() async {
+        await Future.delayed(const Duration(milliseconds: 20));
+        return _isSavingData;
+      });
+    }
+    _isSavingData = true;
     var data = jsonEncode(toJson());
     var file = File(FilePath.join(App.dataPath, 'appdata.json'));
     await file.writeAsString(data);
+    _isSavingData = false;
   }
 
   void addSearchHistory(String keyword) {
@@ -42,8 +52,10 @@ class _Appdata {
     }
     var json = jsonDecode(await file.readAsString());
     for(var key in json['settings'].keys) {
+      if(json[key] != null) {
         settings[key] = json[key];
       }
+    }
     searchHistory = List.from(json['searchHistory']);
   }
 
@@ -88,4 +100,9 @@ class _Settings {
   operator[]=(String key, dynamic value) {
     _data[key] = value;
   }
+
+  @override
+  String toString() {
+    return _data.toString();
+  }
 }

lib/foundation/js_engine.dart

@@ -3,7 +3,6 @@ import 'dart:io';
 import 'dart:math' as math;
 
 import 'package:crypto/crypto.dart';
-import 'package:dio/dio.dart';
 import 'package:flutter/services.dart';
 import 'package:html/parser.dart' as html;
 import 'package:html/dom.dart' as dom;

lib/pages/settings/setting_components.dart

@@ -3,15 +3,12 @@ part of 'settings_page.dart';
 class _SwitchSetting extends StatefulWidget {
   const _SwitchSetting({
     required this.title,
-    this.subtitle,
     required this.settingKey,
     this.onChanged,
   });
 
   final String title;
 
-  final String? subtitle;
-
   final String settingKey;
 
   final VoidCallback? onChanged;
@@ -27,7 +24,6 @@ class _SwitchSettingState extends State<_SwitchSetting> {
 
     return ListTile(
       title: Text(widget.title),
-      subtitle: widget.subtitle == null ? null : Text(widget.subtitle!),
       trailing: Switch(
         value: appdata.settings[widget.settingKey],
         onChanged: (value) {