phase3: util_web + shop_scroll (custom scroll) null-safe; global Key? param fix

lib/dialog/image_viewer.dart

@@ -3,7 +3,7 @@ import 'package:flutter/material.dart';
 import 'package:photo_view/photo_view.dart';
 
 class ImageViewer extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final ImageProvider imageProvider;
 
   ImageViewer(this.imageProvider, {this.key}) :

lib/pages/attribute_selection.dart

@@ -10,7 +10,7 @@ class AttributeSelection extends StatelessWidget {
   final Business business;
   final GlobalKey startKey;
 
-  const AttributeSelection({Key key, this.product, this.business, this.startKey}) : super(key: key);
+  const AttributeSelection({Key? key, this.product, this.business, this.startKey}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/blog.dart

@@ -8,7 +8,7 @@ import '../widgets/desktop/desktop_blog.dart';
 import '../widgets/mobile/mobile_blog.dart';
 
 class Blog extends StatelessWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
 
   const Blog({this.key, int businessId}) :

lib/pages/buy_service.dart

@@ -22,7 +22,7 @@ class BuyService extends StatefulWidget {
   final String domain;
   final int sid;
 
-  const BuyService(this.gid, this.serviceName, {Key key, this.domain, this.sid = 0}) :
+  const BuyService(this.gid, this.serviceName, {Key? key, this.domain, this.sid = 0}) :
       super(key: key);
 
   @override

lib/pages/change_mobile_or_email.dart

@@ -15,7 +15,7 @@ import '../widgets/mobile/mobile_change_mobile_or_email.dart';
 class ChangeMobileOrEmail extends StatelessWidget {
   final bool isMobile;
 
-  const ChangeMobileOrEmail(this.isMobile, {Key key}) : super(key: key);
+  const ChangeMobileOrEmail(this.isMobile, {Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/checkout.dart

@@ -11,7 +11,7 @@ import '../widgets/mobile/mobile_checkout.dart';
 class Checkout extends StatelessWidget {
   final int businessId;
 
-  const Checkout(this.businessId, {Key key}) :
+  const Checkout(this.businessId, {Key? key}) :
       super(key: key);
 
   @override

lib/pages/contact_us.dart

@@ -14,7 +14,7 @@ import '../widgets/mobile/mobile_contact_us.dart';
 class ContactUs extends StatefulWidget {
   final int businessId;
 
-  const ContactUs({this.businessId, Key key}) :
+  const ContactUs({this.businessId, Key? key}) :
       super(key: key);
 
   @override

lib/pages/coupons.dart

@@ -10,7 +10,7 @@ import '../widgets/mobile/mobile_coupons.dart';
 class Coupons extends StatelessWidget {
   final int contactId;
 
-  const Coupons(this.contactId, {Key key}) :
+  const Coupons(this.contactId, {Key? key}) :
       super(key: key);
 
 

lib/pages/create_online_store_1.dart

@@ -11,7 +11,7 @@ import '../widgets/mobile/create_online_store_1.dart' as mobile;
 
 class CreateOnlineStore1 extends StatefulWidget {
 
-  const CreateOnlineStore1({Key key}) :
+  const CreateOnlineStore1({Key? key}) :
       super(key: key);
 
   @override

lib/pages/edit_address.dart

@@ -13,7 +13,7 @@ import '../widgets/general/navigationbar.dart';
 import '../widgets/mobile/MobileBottomNav.dart';
 
 class EditAddress extends StatelessWidget {
-  final Key key;
+  final Key? key;
   final Address address;
   final int businessId;
   const EditAddress(this.address, {this.key, int businessId}) :

lib/pages/forgot_password.dart

@@ -12,7 +12,7 @@ import '../widgets/general/navigationbar.dart';
 import '../widgets/mobile/MobileBottomNav.dart';
 
 class ForgotPassword extends StatelessWidget {
-  const ForgotPassword({Key key}) : super(key: key);
+  const ForgotPassword({Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/igoshow_learn_more.dart

@@ -16,7 +16,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_igoshow_learn_more.dart';
 
 class IGoShowLearnMore extends StatefulWidget {
-  const IGoShowLearnMore({Key key}) : super(key: key);
+  const IGoShowLearnMore({Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/pages/login.dart

@@ -14,7 +14,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_login.dart';
 
 class Login extends StatefulWidget {
-  final Key key;
+  final Key? key;
 
   const Login({this.key}) : super(key: key);
 

lib/pages/me.dart

@@ -15,7 +15,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_me.dart';
 
 class Me extends StatefulWidget {
-  final Key key;
+  final Key? key;
 
   const Me({this.key}) : super(key: key);
 

lib/pages/minipos_learn_more.dart

@@ -16,7 +16,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_minipos_learn_more.dart';
 
 class MiniPosLearnMore extends StatefulWidget {
-  const MiniPosLearnMore({Key key}) : super(key: key);
+  const MiniPosLearnMore({Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/pages/my_addresses.dart

@@ -8,7 +8,7 @@ import '../widgets/desktop/desktop_my_addresses.dart';
 import '../widgets/mobile/mobile_my_addresses.dart';
 
 class MyAddresses extends StatelessWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
 
   const MyAddresses({this.key, int businessId}) :

lib/pages/my_support.dart

@@ -8,7 +8,7 @@ import '../widgets/desktop/desktop_my_support.dart';
 import '../widgets/mobile/mobile_my_support.dart';
 
 class MySupport extends StatelessWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
 
   const MySupport({this.key, int businessId}) :

lib/pages/new_address.dart

@@ -7,7 +7,7 @@ import '../widgets/desktop/desktop_new_address.dart';
 import '../widgets/mobile/mobile_new_address.dart';
 
 class NewAddress extends StatelessWidget {
-  final Key key;
+  final Key? key;
   final LocatedAddress locatedAddress;
   final int businessId;
   const NewAddress({this.key, this.locatedAddress, this.businessId}) : super(key: key);

lib/pages/new_comment.dart

@@ -10,7 +10,7 @@ import '../widgets/mobile/mobile_new_comment.dart';
 class NewComment extends StatelessWidget {
   final int orderId;
 
-  const NewComment(this.orderId, {Key key}) :
+  const NewComment(this.orderId, {Key? key}) :
         super(key: key);
 
 

lib/pages/new_ticket.dart

@@ -14,7 +14,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_new_ticket.dart';
 
 class NewTicket extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
 
   const NewTicket({this.key, int businessId}) :

lib/pages/new_user.dart

@@ -12,7 +12,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_new_user.dart';
 
 class NewUser extends StatelessWidget {
-  const NewUser({Key key}) : super(key: key);
+  const NewUser({Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/order_detail.dart

@@ -11,7 +11,7 @@ class OrderDetail extends StatelessWidget {
   final int orderId;
   final bool fromOrders;
 
-  const OrderDetail(this.orderId, {this.fromOrders = false, Key key}) :
+  const OrderDetail(this.orderId, {this.fromOrders = false, Key? key}) :
       super(key: key);
 
   @override

lib/pages/pay_now.dart

@@ -10,7 +10,7 @@ import '../widgets/mobile/mobile_pay_now.dart';
 class PayNow extends StatelessWidget {
   final int orderId;
 
-  const PayNow(this.orderId, {Key key}) :
+  const PayNow(this.orderId, {Key? key}) :
       super(key: key);
 
 

lib/pages/plain_page.dart

@@ -15,7 +15,7 @@ class PlainPage extends StatefulWidget {
   final int businessId;
   final String slug;
 
-  const PlainPage(this.slug, {this.businessId, Key key}) :
+  const PlainPage(this.slug, {this.businessId, Key? key}) :
       super(key: key);
 
   @override

lib/pages/product_detail_page.dart

@@ -13,7 +13,7 @@ class ProductDetailPage extends StatelessWidget {
   final Business business;
   final Product product;
 
-  const ProductDetailPage({this.business, this.product, Key key}) :
+  const ProductDetailPage({this.business, this.product, Key? key}) :
       super(key: key);
 
 

lib/pages/product_search.dart

@@ -9,7 +9,7 @@ import '../widgets/mobile/product_search.dart' as mobile;
 class ProductSearch extends StatelessWidget {
   final Business business;
 
-  const ProductSearch(this.business, {Key key}) : super(key: key);
+  const ProductSearch(this.business, {Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/renew_license.dart

@@ -12,7 +12,7 @@ import '../widgets/mobile/mobile_renew_license.dart';
 
 class RenewLicense extends StatefulWidget {
 
-  const RenewLicense({Key key}) :
+  const RenewLicense({Key? key}) :
       super(key: key);
 
   @override

lib/pages/renew_minioffice.dart

@@ -17,7 +17,7 @@ import '../widgets/mobile/mobile_renew_license.dart';
 class RenewMiniOffice extends StatefulWidget {
   final int gid;
 
-  const RenewMiniOffice(this.gid, {Key key}) :
+  const RenewMiniOffice(this.gid, {Key? key}) :
       super(key: key);
 
   @override

lib/pages/reset_password.dart

@@ -14,7 +14,7 @@ import '../widgets/mobile/mobile_reset_password.dart';
 class ResetPassword extends StatelessWidget {
   final String mobile;
   final String code;
-  const ResetPassword(this.mobile, {Key key, this.code}) : super(key: key);
+  const ResetPassword(this.mobile, {Key? key, this.code}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/search_place.dart

@@ -5,7 +5,7 @@ import '../widgets/mobile/mobile_search_place.dart';
 import 'package:responsive_builder/responsive_builder.dart';
 
 class SearchPlace extends StatelessWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
   const SearchPlace(this.businessId, {this.key}) : super(key: key);
 

lib/pages/set_password.dart

@@ -14,7 +14,7 @@ import '../widgets/mobile/mobile_set_password.dart';
 class SetPassword extends StatelessWidget {
   final String mobile;
   final String code;
-  const SetPassword(this.mobile, {Key key, this.code}) : super(key: key);
+  const SetPassword(this.mobile, {Key? key, this.code}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/shop.dart

@@ -10,7 +10,7 @@ import '../widgets/mobile/shop.dart' as mobile;
 class Shop extends StatefulWidget {
   final int businessId;
 
-  const Shop({this.businessId, Key key}) : super(key: key);
+  const Shop({this.businessId, Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() => ShopState();

lib/pages/store_product_search.dart

@@ -15,7 +15,7 @@ import '../widgets/mobile/mobile_store_product_search.dart';
 class StoreProductSearch extends StatelessWidget {
   final Business business;
 
-  const StoreProductSearch(this.business, {Key key}) : super(key: key);
+  const StoreProductSearch(this.business, {Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/user_profile.dart

@@ -13,7 +13,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_user_profile.dart';
 
 class UserProfile extends StatelessWidget {
-  const UserProfile({Key key}) : super(key: key);
+  const UserProfile({Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/pages/view_blog.dart

@@ -14,7 +14,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_view_blog.dart';
 
 class ViewBlog extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int bid;
 
   const ViewBlog(this.bid, {this.key}) : super(key: key);

lib/pages/view_ticket.dart

@@ -14,7 +14,7 @@ import '../widgets/mobile/MobileBottomNav.dart';
 import '../widgets/mobile/mobile_view_ticket.dart';
 
 class ViewTicket extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int ticketId;
 
   const ViewTicket(this.ticketId, {this.key}) : super(key: key);

lib/utils/double_back_to_close_app.dart

@@ -21,7 +21,7 @@ class DoubleBackToCloseApp extends StatefulWidget {
   /// Creates a widget that allows the user to close the app by double tapping
   /// the back-button.
   const DoubleBackToCloseApp({
-    Key key,
+    Key? key,
     @required this.snackBar,
     @required this.child,
   })  : assert(snackBar != null),

lib/utils/shop_scroll_controller.dart

@@ -38,7 +38,7 @@ class ShopScrollController extends ScrollController {
   final bool keepScrollOffset;
 
   /// [toString]输出中使用的标签。 旨在帮助在调试输出中标识滚动控制器实例。
-  final String debugLabel;
+  final String? debugLabel;
 
   /// The currently attached positions. 当前附加的 [positions]。
   /// 这不应直接突变。 可以使用[attach]和[detach]添加和删除[ScrollPosition]对象。
@@ -61,7 +61,7 @@ class ShopScrollController extends ScrollController {
         'ScrollController not attached to any scroll views.');
     assert(_positions.length == 1,
         'ScrollController attached to multiple scroll views.');
-    return _positions.single;
+    return _positions.single as ShopScrollPosition;
   }
 
   /// 可滚动小部件的当前滚动偏移量
@@ -83,12 +83,12 @@ class ShopScrollController extends ScrollController {
   /// 持续时间不能为零。 要在没有动画的情况下跳至特定值，请使用[jumpTo]。
   Future<void> animateTo(
     double offset, {
-    @required Duration duration,
-    @required Curve curve,
+    required Duration duration,
+    required Curve curve,
   }) {
     assert(_positions.isNotEmpty,
         'ScrollController not attached to any scroll views.');
-    final List<Future<void>> animations = List<Future<void>>(_positions.length);
+    final List<Future<void>> animations = List<Future<void>>.filled(_positions.length, Future<void>.value());
     for (int i = 0; i < _positions.length; i += 1)
       animations[i] =
           _positions[i].animateTo(offset, duration: duration, curve: curve);
@@ -149,7 +149,7 @@ class ShopScrollController extends ScrollController {
   ///     则它将是前一个实例。 当环境已更改并且[Scrollable]需要重新创建[ScrollPosition]
   ///     对象时，将使用此方法。 第一次创建[ScrollPosition]时为null。
   ScrollPosition createScrollPosition(ScrollPhysics physics,
-      ScrollContext context, ScrollPosition oldPosition) {
+      ScrollContext context, ScrollPosition? oldPosition) {
     return ShopScrollPosition(
       coordinator: coordinator,
       physics: physics,
@@ -175,7 +175,7 @@ class ShopScrollController extends ScrollController {
   @mustCallSuper
   void debugFillDescription(List<String> description) {
     super.debugFillDescription(description);
-    if (debugLabel != null) description.add(debugLabel);
+    if (debugLabel != null) description.add(debugLabel!);
     if (initialScrollOffset != 0.0)
       description.add(
           'initialScrollOffset: ${initialScrollOffset.toStringAsFixed(1)}, ');

lib/utils/shop_scroll_coordinator.dart

@@ -12,15 +12,15 @@ class ShopScrollCoordinator {
   /// 页面主 CustomScrollView 控制
   final String pageLabel = "page";
 
-  ShopScrollController _pageScrollController;
-  double Function() pinnedHeaderSliverHeightBuilder;
+  late ShopScrollController _pageScrollController;
+  double Function()? pinnedHeaderSliverHeightBuilder;
 
   ShopScrollPosition get _pageScrollPosition => _pageScrollController.position;
 
-  ScrollDragController scrollDragController;
+  late ScrollDragController scrollDragController;
 
   /// 主页面滑动部件默认位置
-  double _pageInitialOffset;
+  late double _pageInitialOffset;
 
   /// 获取主页面滑动控制器
   ShopScrollController pageScrollController([double initialOffset = 0.0]) {
@@ -32,26 +32,26 @@ class ShopScrollCoordinator {
   }
 
   /// 创建并获取一个子滑动控制器
-  ShopScrollController newChildScrollController([String debugLabel]) =>
+  ShopScrollController newChildScrollController([String? debugLabel]) =>
       ShopScrollController(this, debugLabel: debugLabel);
 
   /// 子部件滑动数据协调
   /// [userScrollDirection]用户滑动方向
   /// [position]被滑动的子部件的位置信息
   void applyUserOffset(double delta,
-      [ScrollDirection userScrollDirection, ShopScrollPosition position]) {
+      [ScrollDirection? userScrollDirection, ShopScrollPosition? position]) {
     if (userScrollDirection == ScrollDirection.reverse) {
-      updateUserScrollDirection(_pageScrollPosition, userScrollDirection);
+      updateUserScrollDirection(_pageScrollPosition, userScrollDirection!);
       final innerDelta = _pageScrollPosition.applyClampedDragUpdate(delta);
       if (innerDelta != 0.0) {
-        updateUserScrollDirection(position, userScrollDirection);
+        updateUserScrollDirection(position!, userScrollDirection);
         position.applyFullDragUpdate(innerDelta);
       }
     } else {
-      updateUserScrollDirection(position, userScrollDirection);
+      updateUserScrollDirection(position!, userScrollDirection!);
       final outerDelta = position.applyClampedDragUpdate(delta);
       if (outerDelta != 0.0) {
-        updateUserScrollDirection(_pageScrollPosition, userScrollDirection);
+        updateUserScrollDirection(_pageScrollPosition, userScrollDirection!);
         _pageScrollPosition.applyFullDragUpdate(outerDelta);
       }
     }
@@ -60,7 +60,7 @@ class ShopScrollCoordinator {
   bool applyContentDimensions(double minScrollExtent, double maxScrollExtent,
       ShopScrollPosition position) {
     if (pinnedHeaderSliverHeightBuilder != null) {
-      maxScrollExtent = maxScrollExtent - pinnedHeaderSliverHeightBuilder();
+      maxScrollExtent = maxScrollExtent - pinnedHeaderSliverHeightBuilder!();
       maxScrollExtent = math.max(0.0, maxScrollExtent);
     }
     return position.applyContentDimensions(

lib/utils/shop_scroll_position.dart

@@ -11,17 +11,17 @@ import 'shop_scroll_coordinator.dart';
 class ShopScrollPosition extends ScrollPosition
     implements ScrollActivityDelegate {
   final ShopScrollCoordinator coordinator; // 协调器
-  ScrollDragController _currentDrag;
+  ScrollDragController? _currentDrag;
   double _heldPreviousVelocity = 0.0;
 
   ShopScrollPosition(
-      {@required ScrollPhysics physics,
-      @required ScrollContext context,
+      {required ScrollPhysics physics,
+      required ScrollContext context,
       double initialPixels = 0.0,
       bool keepScrollOffset = true,
-      ScrollPosition oldPosition,
-      String debugLabel,
-      @required this.coordinator})
+      ScrollPosition? oldPosition,
+      String? debugLabel,
+      required this.coordinator})
       : super(
           physics: physics,
           context: context,
@@ -40,7 +40,7 @@ class ShopScrollPosition extends ScrollPosition
 
   @override
   double setPixels(double newPixels) {
-    assert(activity.isScrolling);
+    assert(activity!.isScrolling);
     return super.setPixels(newPixels);
   }
 
@@ -51,13 +51,13 @@ class ShopScrollPosition extends ScrollPosition
       goIdle();
       return;
     }
-    activity.updateDelegate(this);
+    activity!.updateDelegate(this);
     final ShopScrollPosition typedOther = other as ShopScrollPosition;
     _userScrollDirection = typedOther._userScrollDirection;
     assert(_currentDrag == null);
     if (typedOther._currentDrag != null) {
       _currentDrag = typedOther._currentDrag;
-      _currentDrag.updateDelegate(this);
+      _currentDrag!.updateDelegate(this);
       typedOther._currentDrag = null;
     }
   }
@@ -131,14 +131,14 @@ class ShopScrollPosition extends ScrollPosition
   }
 
   @override
-  void beginActivity(ScrollActivity newActivity) {
+  void beginActivity(ScrollActivity? newActivity) {
     _heldPreviousVelocity = 0.0;
     if (newActivity == null) return;
     assert(newActivity.delegate == this);
     super.beginActivity(newActivity);
     _currentDrag?.dispose();
     _currentDrag = null;
-    if (!activity.isScrolling) updateUserScrollDirection(ScrollDirection.idle);
+    if (!activity!.isScrolling) updateUserScrollDirection(ScrollDirection.idle);
   }
 
   /// 将[用户滚动方向]设置为给定值。
@@ -154,7 +154,7 @@ class ShopScrollPosition extends ScrollPosition
 
   @override
   ScrollHoldController hold(VoidCallback holdCancelCallback) {
-    final double previousVelocity = activity.velocity;
+    final double previousVelocity = activity!.velocity;
     final HoldScrollActivity holdActivity =
         HoldScrollActivity(delegate: this, onHoldCanceled: holdCancelCallback);
     beginActivity(holdActivity);
@@ -195,10 +195,10 @@ class ShopScrollPosition extends ScrollPosition
       if (coordinator.pageExpand == PageExpandState.Expanding) return;
     }
     assert(pixels != null);
-    final Simulation simulation =
+    final Simulation? simulation =
         physics.createBallisticSimulation(this, velocity);
     if (simulation != null) {
-      beginActivity(BallisticScrollActivity(this, simulation, context.vsync));
+      beginActivity(BallisticScrollActivity(this, simulation, context.vsync, false));
     } else {
       goIdle();
     }
@@ -220,8 +220,8 @@ class ShopScrollPosition extends ScrollPosition
   @override
   Future<void> animateTo(
     double to, {
-    @required Duration duration,
-    @required Curve curve,
+    required Duration duration,
+    required Curve curve,
   }) {
     if (nearEqual(to, pixels, physics.tolerance.distance)) {
       // 跳过动画，直接移到我们已经靠近的位置。

lib/widgets/desktop/create_online_store_1.dart

@@ -15,7 +15,7 @@ import '../../widgets/general/navigationbar.dart';
 class CreateOnlineStore1 extends StatefulWidget {
   final int businessId;
 
-  const CreateOnlineStore1(this.businessId, {Key key}) : super(key: key);
+  const CreateOnlineStore1(this.businessId, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_blog.dart

@@ -24,7 +24,7 @@ import '../../utils/util_web.dart' if (dart.library.io) '../../utils/util_io.dar
 
 class DesktopBlog extends StatefulWidget {
   final int businessId;
-  const DesktopBlog({Key key, this.businessId}) : super(key: key);
+  const DesktopBlog({Key? key, this.businessId}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_buy_service.dart

@@ -15,7 +15,7 @@ import '../../widgets/general/navigationbar.dart';
 class DesktopBuyService extends StatefulWidget {
   final Map<String, dynamic> data;
 
-  const DesktopBuyService(this.data, {Key key})
+  const DesktopBuyService(this.data, {Key? key})
       : super(key: key);
 
   @override

lib/widgets/desktop/desktop_change_mobile_or_email.dart

@@ -16,7 +16,7 @@ import '../../utils/utils.dart';
 class DesktopChangeMobileOrEmail extends StatefulWidget {
   final bool isMobile;
 
-  const DesktopChangeMobileOrEmail(this.isMobile, {Key key}) : super(key: key);
+  const DesktopChangeMobileOrEmail(this.isMobile, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_change_password.dart

@@ -8,7 +8,7 @@ import '../../utils/utils.dart';
 import '../../widgets/general/breadcrumbs.dart';
 
 class DesktopChangePassword extends StatefulWidget {
-  const DesktopChangePassword({Key key}) : super(key: key);
+  const DesktopChangePassword({Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_checkout.dart

@@ -34,7 +34,7 @@ import '../../utils/utils.dart';
 import '../../widgets/general/sliding_up_panel.dart';
 
 class DesktopCheckout extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
 
   const DesktopCheckout(this.businessId, {this.key,}) : super(key: key);

lib/widgets/desktop/desktop_contact_us.dart

@@ -19,7 +19,7 @@ import '../../utils/util_web.dart' if (dart.library.io) '../../utils/util_io.dar
 class DesktopContactUs extends StatefulWidget {
   final Business business;
 
-  const DesktopContactUs(this.business, {Key key}) : super(key: key);
+  const DesktopContactUs(this.business, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_coupons.dart

@@ -17,7 +17,7 @@ import '../../widgets/general/navigationbar.dart';
 
 class DesktopCoupons extends StatefulWidget {
   final int contactId;
-  final Key key;
+  final Key? key;
   const DesktopCoupons(this.contactId, {this.key});
 
   @override

lib/widgets/desktop/desktop_download_apps.dart

@@ -9,7 +9,7 @@ import '../../utils/util_web.dart' if (dart.library.io) '../../utils/util_io.dar
 class DesktopDownloadApps extends StatefulWidget {
   final Map<String, dynamic> data;
 
-  DesktopDownloadApps(this.data, {Key key}) : super(key: key);
+  DesktopDownloadApps(this.data, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_edit_address.dart

@@ -20,7 +20,7 @@ import '../../utils/utils.dart';
 import '../../widgets/general/navigationbar.dart';
 
 class DesktopEditAddress extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final Address address;
   final int businessId;
   const DesktopEditAddress(this.address, {this.key, int businessId}) :

lib/widgets/desktop/desktop_forgot_password.dart

@@ -13,7 +13,7 @@ import '../../utils/http_util.dart';
 import '../../utils/utils.dart';
 
 class DesktopForgotPassword extends StatefulWidget {
-  const DesktopForgotPassword({Key key}) : super(key: key);
+  const DesktopForgotPassword({Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_igoshow_learn_more.dart

@@ -8,7 +8,7 @@ import '../../widgets/general/breadcrumbs.dart';
 
 class DesktopiGoShowLearnMore extends StatefulWidget {
   final Map<String, dynamic> data;
-  const DesktopiGoShowLearnMore(this.data, {Key key}) : super(key: key);
+  const DesktopiGoShowLearnMore(this.data, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_login.dart

@@ -11,7 +11,7 @@ import '../../utils/http_util.dart';
 import '../../utils/utils.dart';
 
 class DesktopLogin extends StatefulWidget {
-  final Key key;
+  final Key? key;
 
   const DesktopLogin({this.key}) : super(key: key);
 

lib/widgets/desktop/desktop_me.dart

@@ -21,7 +21,7 @@ double statusBarHeight;
 double screenHeight;
 
 class DesktopMe extends StatefulWidget {
-  final Key key;
+  final Key? key;
 
   const DesktopMe({this.key}) : super(key: key);
 

lib/widgets/desktop/desktop_minipos_learn_more.dart

@@ -7,7 +7,7 @@ import '../../widgets/general/breadcrumbs.dart';
 
 class DesktopMiniPosLearnMore extends StatefulWidget {
   final Map<String, dynamic> data;
-  const DesktopMiniPosLearnMore(this.data, {Key key}) : super(key: key);
+  const DesktopMiniPosLearnMore(this.data, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_my_addresses.dart

@@ -20,7 +20,7 @@ import '../../widgets/general/navigationbar.dart';
 
 class DesktopMyAddresses extends StatefulWidget {
   final int businessId;
-  const DesktopMyAddresses({Key key, this.businessId}) : super(key: key);
+  const DesktopMyAddresses({Key? key, this.businessId}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_my_support.dart

@@ -20,7 +20,7 @@ import '../../widgets/general/navigationbar.dart';
 
 class DesktopMySupport extends StatefulWidget {
   final int businessId;
-  const DesktopMySupport({Key key, this.businessId}) : super(key: key);
+  const DesktopMySupport({Key? key, this.businessId}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_new_address.dart

@@ -14,7 +14,7 @@ import '../../utils/http_util.dart';
 import '../../widgets/general/navigationbar.dart';
 
 class DesktopNewAddress extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final LocatedAddress locatedAddress;
   final int businessId;
   const DesktopNewAddress({this.key, this.locatedAddress, this.businessId}) : super(key: key);

lib/widgets/desktop/desktop_new_comment.dart

@@ -22,7 +22,7 @@ import '../../utils/utils.dart';
 
 
 class DesktopNewComment extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int orderId;
   const DesktopNewComment(this.orderId, {this.key});
 

lib/widgets/desktop/desktop_new_ticket.dart

@@ -18,7 +18,7 @@ import '../../widgets/general/breadcrumbs.dart';
 import '../../utils/util_web.dart' if (dart.library.io) '../../utils/util_io.dart';
 
 class DesktopNewTicket extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
 
   const DesktopNewTicket({this.key, int businessId}) :

lib/widgets/desktop/desktop_new_user.dart

@@ -11,7 +11,7 @@ import '../../utils/http_util.dart';
 import '../../utils/utils.dart';
 
 class DesktopNewUser extends StatefulWidget {
-  const DesktopNewUser({Key key}) : super(key: key);
+  const DesktopNewUser({Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_order_detail.dart

@@ -26,7 +26,7 @@ import '../../widgets/general/breadcrumbs.dart';
 import '../../widgets/general/navigationbar.dart';
 
 class DesktopOrderDetail extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int orderId;
   final bool fromOrders;
   const DesktopOrderDetail(this.orderId, {this.key, this.fromOrders});

lib/widgets/desktop/desktop_orders.dart

@@ -22,7 +22,7 @@ import '../../widgets/general/navigationbar.dart';
 
 
 class DesktopOrders extends StatefulWidget {
-  final Key key;
+  final Key? key;
   const DesktopOrders({this.key});
 
   @override

lib/widgets/desktop/desktop_pay_now.dart

@@ -20,7 +20,7 @@ import '../../utils/util_web.dart' if (dart.library.io) '../../utils/util_io.dar
 import '../../utils/utils.dart';
 
 class DesktopPayNow extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int orderId;
   const DesktopPayNow(this.orderId, {this.key});
 

lib/widgets/desktop/desktop_plain_page.dart

@@ -13,7 +13,7 @@ import '../../widgets/general/navigationbar.dart';
 class DesktopPlainPage extends StatefulWidget {
   final Blog blog;
 
-  const DesktopPlainPage(this.blog, {Key key}) : super(key: key);
+  const DesktopPlainPage(this.blog, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_product_detail_page.dart

@@ -30,7 +30,7 @@ class DesktopProductDetailPage extends StatefulWidget {
   final Product product;
 
   const DesktopProductDetailPage(
-      {@required this.business, @required this.product, Key key})
+      {@required this.business, @required this.product, Key? key})
       : super(key: key);
 
   @override

lib/widgets/desktop/desktop_product_item.dart

@@ -17,7 +17,7 @@ class DesktopProductItem extends StatefulWidget {
   final Business business;
   final bool horizontal;
 
-  DesktopProductItem({this.product, this.business, Key key, this.horizontal = false})
+  DesktopProductItem({this.product, this.business, Key? key, this.horizontal = false})
     : super(key: key);
 
   @override

lib/widgets/desktop/desktop_renew_license.dart

@@ -16,7 +16,7 @@ import '../../widgets/general/navigationbar.dart';
 class DesktopRenewLicense extends StatefulWidget {
   final int businessId;
 
-  const DesktopRenewLicense(this.businessId, {Key key}) : super(key: key);
+  const DesktopRenewLicense(this.businessId, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_renew_minioffice.dart

@@ -17,7 +17,7 @@ import '../../widgets/general/navigationbar.dart';
 class DesktopRenewMiniOffice extends StatefulWidget {
   final Map<String, dynamic> data;
 
-  const DesktopRenewMiniOffice(this.data, {Key key}) : super(key: key);
+  const DesktopRenewMiniOffice(this.data, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/desktop/desktop_reset_password.dart

@@ -12,7 +12,7 @@ class DesktopResetPassword extends StatefulWidget {
   final String mobile;
   final String code;
 
-  const DesktopResetPassword(this.mobile, {this.code, Key key}) :
+  const DesktopResetPassword(this.mobile, {this.code, Key? key}) :
       super(key: key);
 
   @override

lib/widgets/desktop/desktop_search_place.dart

@@ -17,7 +17,7 @@ import '../../utils/http_util.dart';
 import '../../utils/utils.dart';
 
 class DesktopSearchPlace extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
   const DesktopSearchPlace(this.businessId, {this.key}) : super(key: key);
 

lib/widgets/desktop/desktop_set_password.dart

@@ -12,7 +12,7 @@ class DesktopSetPassword extends StatefulWidget {
   final String mobile;
   final String code;
 
-  const DesktopSetPassword(this.mobile, {this.code, Key key}) :
+  const DesktopSetPassword(this.mobile, {this.code, Key? key}) :
       super(key: key);
 
   @override

lib/widgets/desktop/desktop_store_product_search.dart

@@ -19,7 +19,7 @@ import '../../utils/utils.dart';
 import '../../widgets/general/add_remove_button.dart';
 
 class DesktopStoreProductSearch extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final Business business;
 
   const DesktopStoreProductSearch(this.business, {this.key});

lib/widgets/desktop/desktop_user_profile.dart

@@ -15,7 +15,7 @@ import '../../utils/util_web.dart' if (dart.library.io) '../../utils/util_io.dar
 import '../../utils/utils.dart';
 
 class DesktopUserProfile extends StatefulWidget {
-  final Key key;
+  final Key? key;
 
   const DesktopUserProfile({this.key})
       : super(key: key);

lib/widgets/desktop/desktop_view_blog.dart

@@ -16,7 +16,7 @@ import '../../widgets/general/breadcrumbs.dart';
 import '../../utils/util_io.dart' if (dart.library.html) '../../utils/util_web.dart';
 
 class DesktopViewBlog extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int bid;
 
   const DesktopViewBlog(this.bid, {this.key}) : super(key: key);

lib/widgets/desktop/desktop_view_ticket.dart

@@ -19,7 +19,7 @@ import '../../utils/utils.dart';
 import '../../widgets/general/text_link.dart';
 
 class DesktopViewTicket extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int ticketId;
 
   const DesktopViewTicket(this.ticketId, {this.key}) : super(key: key);

lib/widgets/desktop/product_item.dart

@@ -17,7 +17,7 @@ class ProductItem extends StatefulWidget {
   final Product product;
   final bool horizontal;
 
-  const ProductItem(this.product, this.business, {Key key, this.horizontal = false}) : super(key: key);
+  const ProductItem(this.product, this.business, {Key? key, this.horizontal = false}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() => ProductItemState();

lib/widgets/desktop/product_search.dart

@@ -20,7 +20,7 @@ import 'product_item.dart';
 class ProductSearch extends StatefulWidget {
   final Business business;
 
-  const ProductSearch(this.business, {Key key}) : super(key: key);
+  const ProductSearch(this.business, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() => ProductSearchState();

lib/widgets/desktop/shop.dart

@@ -24,7 +24,7 @@ import 'shopping_cart_widget.dart';
 class Shop extends StatefulWidget {
   final int businessId;
 
-  const Shop({Key key, this.businessId}): super(key: key);
+  const Shop({Key? key, this.businessId}): super(key: key);
 
   @override
   State<StatefulWidget> createState() => ShopState();

lib/widgets/desktop/shop_bulletin.dart

@@ -7,7 +7,7 @@ import '../../models/business.dart';
 class ShopBulletin extends StatefulWidget {
   final Business business;
 
-  const ShopBulletin(this.business, {Key key}): super(key: key);
+  const ShopBulletin(this.business, {Key? key}): super(key: key);
 
   @override
   State<StatefulWidget> createState() => ShopBulletinState();

lib/widgets/desktop/shop_products.dart

@@ -16,7 +16,7 @@ import '../../widgets/desktop/product_item.dart';
 class ShopProducts extends StatefulWidget {
   final dynamic data;
 
-  const ShopProducts(this.data, {Key key}): super(key: key);
+  const ShopProducts(this.data, {Key? key}): super(key: key);
 
   @override
   State<StatefulWidget> createState() => ShopProductsState();

lib/widgets/desktop/shop_promote.dart

@@ -12,7 +12,7 @@ import '../../utils/util_io.dart' if (dart.library.html) '../../utils/util_web.d
 class ShopPromote extends StatefulWidget {
   final dynamic data;
 
-  const ShopPromote(this.data, {Key key}): super(key: key);
+  const ShopPromote(this.data, {Key? key}): super(key: key);
 
   @override
   State<StatefulWidget> createState() => ShopPromoteState();

lib/widgets/general/carousel.dart

@@ -102,7 +102,7 @@ class CarouselState extends State<Carousel> {
 }
 
 class Indicator extends StatefulWidget {
-  Indicator({Key key, int count})
+  Indicator({Key? key, int count})
       : count = count,
         super(key: key);
 

lib/widgets/general/download_item.dart

@@ -13,7 +13,7 @@ import '../../utils/utils.dart';
 class DownloadItem extends StatefulWidget {
   final dynamic desc;
   final double width;
-  const DownloadItem(this.desc, {Key key, this.width}) : super(key: key);
+  const DownloadItem(this.desc, {Key? key, this.width}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/general/hover_widget.dart

@@ -1,3 +1,4 @@
+import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
 
 /// 自定义实现，替代已停维的 `hovering` 包的 [HoverWidget]。

lib/widgets/general/index_carousel.dart

@@ -7,7 +7,7 @@ import 'package:responsive_builder/responsive_builder.dart';
 
 class IndexCarousel extends StatelessWidget {
   final List<Gallery> galleries;
-  const IndexCarousel(this.galleries, {Key key}) : super(key: key);
+  const IndexCarousel(this.galleries, {Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/widgets/general/index_main_content_1.dart

@@ -6,7 +6,7 @@ import 'package:responsive_builder/responsive_builder.dart';
 
 class IndexMainContent1 extends StatelessWidget {
   final String message;
-  const IndexMainContent1(this.message, {Key key}) : super(key: key);
+  const IndexMainContent1(this.message, {Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/widgets/general/index_main_content_2.dart

@@ -6,7 +6,7 @@ import 'package:responsive_builder/responsive_builder.dart';
 
 class IndexMainContent2 extends StatelessWidget {
   final Map<String, dynamic> content;
-  const IndexMainContent2(this.content, {Key key}) : super(key: key);
+  const IndexMainContent2(this.content, {Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/widgets/general/index_main_content_3.dart

@@ -6,7 +6,7 @@ import 'package:responsive_builder/responsive_builder.dart';
 
 class IndexMainContent3 extends StatelessWidget {
   final Map<String, dynamic> content;
-  const IndexMainContent3(this.content, {Key key}) : super(key: key);
+  const IndexMainContent3(this.content, {Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {

lib/widgets/general/navigationbar_logo.dart

@@ -4,7 +4,7 @@ import 'package:flutter/material.dart';
 import '../../constants.dart';
 
 class NavigationBarLogo extends StatelessWidget {
-  const NavigationBarLogo({Key key}) : super(key: key);
+  const NavigationBarLogo({Key? key}) : super(key: key);
 
   static const IconData logoData = IconData(
       Constants.FONT_WISETRONIC,

lib/widgets/general/payment_verification_code_dialog.dart

@@ -12,7 +12,7 @@ typedef OnCodeVerified();
 typedef OnCancel();
 
 class PaymentVerificationCodeDialog extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final User user;
   final OnCodeVerified onCodeVerified;
   final OnCancel onCancel;

lib/widgets/general/read_more_text.dart

@@ -9,7 +9,7 @@ enum TrimMode {
 class ReadMoreText extends StatefulWidget {
   const ReadMoreText(
       this.data, {
-        Key key,
+        Key? key,
         this.trimExpandedText = ' read less',
         this.trimCollapsedText = ' ...read more',
         this.colorClickableText,

lib/widgets/general/sliding_up_panel.dart

@@ -164,7 +164,7 @@ class SlidingUpPanel extends StatefulWidget {
   final PanelState defaultPanelState;
 
   SlidingUpPanel({
-    Key key,
+    Key? key,
     this.panel,
     this.panelBuilder,
     this.body,

lib/widgets/mobile/create_online_store_1.dart

@@ -12,7 +12,7 @@ import '../../utils/utils.dart';
 class CreateOnlineStore1 extends StatefulWidget {
   final int businessId;
 
-  const CreateOnlineStore1(this.businessId, {Key key}) : super(key: key);
+  const CreateOnlineStore1(this.businessId, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/mobile/mobile_attribute_selection.dart

@@ -19,7 +19,7 @@ import '../../widgets/general/attribute/radio_options.dart';
 class MobileAttributeSelection extends StatefulWidget {
   final Product product;
   final Business business;
-  final Key key;
+  final Key? key;
   final GlobalKey startKey;
 
   const MobileAttributeSelection({@required this.product, @required this.business, this.key, this.startKey})

lib/widgets/mobile/mobile_blog.dart

@@ -18,7 +18,7 @@ import '../../widgets/mobile/MobileBottomNav.dart';
 
 class MobileBlog extends StatefulWidget {
   final int businessId;
-  const MobileBlog({Key key, this.businessId}) : super(key: key);
+  const MobileBlog({Key? key, this.businessId}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/mobile/mobile_buy_service.dart

@@ -11,7 +11,7 @@ import '../../utils/utils.dart';
 class MobileBuyService extends StatefulWidget {
   final Map<String, dynamic> data;
 
-  const MobileBuyService(this.data, {Key key})
+  const MobileBuyService(this.data, {Key? key})
       : super(key: key);
 
   @override

lib/widgets/mobile/mobile_change_mobile_or_email.dart

@@ -15,7 +15,7 @@ import '../../utils/utils.dart';
 class MobileChangeMobileOrEmail extends StatefulWidget {
   final bool isMobile;
 
-  const MobileChangeMobileOrEmail(this.isMobile, {Key key}) : super(key: key);
+  const MobileChangeMobileOrEmail(this.isMobile, {Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/mobile/mobile_change_password.dart

@@ -6,7 +6,7 @@ import '../../utils/utils.dart';
 import '../../generated/l10n.dart';
 
 class MobileChangePassword extends StatefulWidget {
-  const MobileChangePassword({Key key}) : super(key: key);
+  const MobileChangePassword({Key? key}) : super(key: key);
 
   @override
   State<StatefulWidget> createState() {

lib/widgets/mobile/mobile_checkout.dart

@@ -32,7 +32,7 @@ import '../../utils/utils.dart';
 import '../../widgets/general/sliding_up_panel.dart';
 
 class MobileCheckout extends StatefulWidget {
-  final Key key;
+  final Key? key;
   final int businessId;
 
   const MobileCheckout(this.businessId, {this.key,}) : super(key: key);