diff --git a/lib/widgets/desktop/create_online_store_1.dart b/lib/widgets/desktop/create_online_store_1.dart
index 416c860..587825f 100644
--- a/lib/widgets/desktop/create_online_store_1.dart
+++ b/lib/widgets/desktop/create_online_store_1.dart
@@ -283,7 +283,7 @@ class CreateOnlineStore1State extends State<CreateOnlineStore1> {
                         fontSize: 18.0
                     ),
                     autofocus: true,
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).domains_separated_comma;
                       }
diff --git a/lib/widgets/desktop/desktop_change_mobile_or_email.dart b/lib/widgets/desktop/desktop_change_mobile_or_email.dart
index 83dfebf..9e7717c 100644
--- a/lib/widgets/desktop/desktop_change_mobile_or_email.dart
+++ b/lib/widgets/desktop/desktop_change_mobile_or_email.dart
@@ -87,7 +87,7 @@ class DesktopChangeMobileOrEmailState extends State<DesktopChangeMobileOrEmail>
                         fontSize: 18.0
                     ),
                     autofocus: true,
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         if (widget.isMobile) {
                           return S
@@ -184,7 +184,7 @@ class DesktopChangeMobileOrEmailState extends State<DesktopChangeMobileOrEmail>
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).verification_code_is_required;
                       }
@@ -217,7 +217,7 @@ class DesktopChangeMobileOrEmailState extends State<DesktopChangeMobileOrEmail>
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).submit_to_change,
diff --git a/lib/widgets/desktop/desktop_change_password.dart b/lib/widgets/desktop/desktop_change_password.dart
index b6e0203..75f2488 100644
--- a/lib/widgets/desktop/desktop_change_password.dart
+++ b/lib/widgets/desktop/desktop_change_password.dart
@@ -137,7 +137,7 @@ class DesktopChangePasswordState extends State<DesktopChangePassword> {
                                     style: TextStyle(
                                         fontSize: 18.0
                                     ),
-                                    validator: (String value) {
+                                    validator: (String? value) {
                                       if (value.trim().isEmpty) {
                                         return S.of(context).current_password_is_required;
                                       }
@@ -191,7 +191,7 @@ class DesktopChangePasswordState extends State<DesktopChangePassword> {
                                     style: TextStyle(
                                         fontSize: 18.0
                                     ),
-                                    validator: (String value) {
+                                    validator: (String? value) {
                                       if (value.trim().isEmpty) {
                                         return S.of(context).password_is_required;
                                       }
@@ -245,7 +245,7 @@ class DesktopChangePasswordState extends State<DesktopChangePassword> {
                                     style: TextStyle(
                                         fontSize: 18.0
                                     ),
-                                    validator: (String value) {
+                                    validator: (String? value) {
                                       if (value.trim().isEmpty) {
                                         return S.of(context).password_is_required;
                                       }
@@ -282,7 +282,7 @@ class DesktopChangePasswordState extends State<DesktopChangePassword> {
                             alignment: Alignment.centerRight,
                             child: ElevatedButton(
                               style: ElevatedButton.styleFrom(
-                                primary: Theme.of(context).primaryColor,
+                                backgroundColor: Theme.of(context).primaryColor,
                               ),
                               child: Text(
                                 S.of(context).submit,
diff --git a/lib/widgets/desktop/desktop_checkout.dart b/lib/widgets/desktop/desktop_checkout.dart
index a36599a..a171431 100644
--- a/lib/widgets/desktop/desktop_checkout.dart
+++ b/lib/widgets/desktop/desktop_checkout.dart
@@ -127,7 +127,7 @@ class DesktopCheckoutState extends State<DesktopCheckout> with SingleTickerProvi
                 ),
                 ElevatedButton(
                   style: ElevatedButton.styleFrom(
-                    primary: Theme.of(context).primaryColor,
+                    backgroundColor: Theme.of(context).primaryColor,
                   ),
                   child: Text(
                     S.of(context).ok,
@@ -1652,7 +1652,7 @@ class DesktopCheckoutState extends State<DesktopCheckout> with SingleTickerProvi
                   ),
                   labelText: S.of(context).enter_coupon_code,
                 ),
-                validator: (String value) {
+                validator: (String? value) {
                   return null;
                 },
               ),
diff --git a/lib/widgets/desktop/desktop_coupons.dart b/lib/widgets/desktop/desktop_coupons.dart
index f3c8541..d59408d 100644
--- a/lib/widgets/desktop/desktop_coupons.dart
+++ b/lib/widgets/desktop/desktop_coupons.dart
@@ -271,7 +271,7 @@ class DesktopCouponsState extends State<DesktopCoupons> {
           Container(
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
                 shape: RoundedRectangleBorder(
                   borderRadius: BorderRadius.circular(20.0),
                 ),
diff --git a/lib/widgets/desktop/desktop_edit_address.dart b/lib/widgets/desktop/desktop_edit_address.dart
index c05010d..5fff4e7 100644
--- a/lib/widgets/desktop/desktop_edit_address.dart
+++ b/lib/widgets/desktop/desktop_edit_address.dart
@@ -105,7 +105,7 @@ class DesktopEditAddressState extends State<DesktopEditAddress> {
                     .of(context)
                     .contact_name,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value
                     .trim()
                     .isEmpty) {
@@ -160,7 +160,7 @@ class DesktopEditAddressState extends State<DesktopEditAddress> {
                     .of(context)
                     .mobile_phone_number,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value
                     .trim()
                     .isEmpty) {
@@ -192,7 +192,7 @@ class DesktopEditAddressState extends State<DesktopEditAddress> {
                     .of(context)
                     .street_line_1,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value
                     .trim()
                     .isEmpty) {
@@ -246,7 +246,7 @@ class DesktopEditAddressState extends State<DesktopEditAddress> {
                     .of(context)
                     .city,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value
                     .trim()
                     .isEmpty) {
@@ -316,7 +316,7 @@ class DesktopEditAddressState extends State<DesktopEditAddress> {
                     .of(context)
                     .postal_code,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value
                     .trim()
                     .isEmpty) {
@@ -361,7 +361,7 @@ class DesktopEditAddressState extends State<DesktopEditAddress> {
                     .of(context)
                     .email,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.isNotEmpty && !EmailValidator.validate(value)) {
                   return S
                       .of(context)
diff --git a/lib/widgets/desktop/desktop_forgot_password.dart b/lib/widgets/desktop/desktop_forgot_password.dart
index bca07d9..e130b55 100644
--- a/lib/widgets/desktop/desktop_forgot_password.dart
+++ b/lib/widgets/desktop/desktop_forgot_password.dart
@@ -83,7 +83,7 @@ class DesktopForgotPasswordState extends State<DesktopForgotPassword> {
                         fontSize: 18.0
                     ),
                     autofocus: true,
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).mobile_or_email_is_required;
                       }
@@ -166,7 +166,7 @@ class DesktopForgotPasswordState extends State<DesktopForgotPassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).verification_code_is_required;
                       }
@@ -199,7 +199,7 @@ class DesktopForgotPasswordState extends State<DesktopForgotPassword> {
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).verify,
diff --git a/lib/widgets/desktop/desktop_login.dart b/lib/widgets/desktop/desktop_login.dart
index 8916c83..aeedb35 100644
--- a/lib/widgets/desktop/desktop_login.dart
+++ b/lib/widgets/desktop/desktop_login.dart
@@ -149,7 +149,7 @@ class DesktopLoginState extends State<DesktopLogin> {
                                 ),
                                 style: TextStyle(fontSize: 18.0),
                                 autofocus: true,
-                                validator: (String value) {
+                                validator: (String? value) {
                                   if (value.trim().isEmpty) {
                                     return S.of(context).this_field_is_required;
                                   }
@@ -193,7 +193,7 @@ class DesktopLoginState extends State<DesktopLogin> {
                                 ),
                                 style: TextStyle(fontSize: 18.0),
                                 obscureText: passwordVisible,
-                                validator: (String value) {
+                                validator: (String? value) {
                                   if (value.trim().isEmpty) {
                                     return S.of(context).password_is_required;
                                   }
@@ -248,7 +248,7 @@ class DesktopLoginState extends State<DesktopLogin> {
                               top: 20.0, left: 16.0, right: 16.0, bottom: 20.0),
                           child: ElevatedButton(
                             style: ElevatedButton.styleFrom(
-                              primary: Theme.of(context).primaryColor,
+                              backgroundColor: Theme.of(context).primaryColor,
                             ),
                             child: Text(
                               S.of(context).login,
diff --git a/lib/widgets/desktop/desktop_new_address.dart b/lib/widgets/desktop/desktop_new_address.dart
index d7aacc7..d3e49d6 100644
--- a/lib/widgets/desktop/desktop_new_address.dart
+++ b/lib/widgets/desktop/desktop_new_address.dart
@@ -97,7 +97,7 @@ class DesktopNewAddressState extends State<DesktopNewAddress> {
                 ),
                 labelText: S.of(context).contact_name,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.trim().isEmpty) {
                   return S.of(context).contact_name_is_required;
                 }
@@ -141,7 +141,7 @@ class DesktopNewAddressState extends State<DesktopNewAddress> {
                 ),
                 labelText: S.of(context).mobile_phone_number,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.trim().isEmpty) {
                   return S.of(context).mobile_phone_number_is_required;
                 }
@@ -166,7 +166,7 @@ class DesktopNewAddressState extends State<DesktopNewAddress> {
                 ),
                 labelText: S.of(context).street_line_1,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.trim().isEmpty) {
                   return S.of(context).street_line_1_is_required;
                 }
@@ -210,7 +210,7 @@ class DesktopNewAddressState extends State<DesktopNewAddress> {
                 ),
                 labelText: S.of(context).city,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.trim().isEmpty) {
                   return S.of(context).city_is_required;
                 }
@@ -256,7 +256,7 @@ class DesktopNewAddressState extends State<DesktopNewAddress> {
                 ),
                 labelText: S.of(context).postal_code,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.trim().isEmpty) {
                   return S.of(context).postal_code_is_required;
                 }
@@ -291,7 +291,7 @@ class DesktopNewAddressState extends State<DesktopNewAddress> {
                 ),
                 labelText: S.of(context).email,
               ),
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.isNotEmpty && !EmailValidator.validate(value)) {
                   return S.of(context).email_is_not_valid;
                 }
diff --git a/lib/widgets/desktop/desktop_new_comment.dart b/lib/widgets/desktop/desktop_new_comment.dart
index b322f1b..77498f2 100644
--- a/lib/widgets/desktop/desktop_new_comment.dart
+++ b/lib/widgets/desktop/desktop_new_comment.dart
@@ -175,7 +175,7 @@ class DesktopNewCommentState extends State<DesktopNewComment> {
                       ),
                     ),
                     style: ElevatedButton.styleFrom(
-                      primary: Theme.of(context).primaryColor,
+                      backgroundColor: Theme.of(context).primaryColor,
                     ),
                     onPressed: () {
                       _submit();
@@ -246,7 +246,7 @@ class DesktopNewCommentState extends State<DesktopNewComment> {
                               Navigator.of(context).pop();
                             },
                             style: TextButton.styleFrom(
-                              primary: Theme.of(context).primaryColor,
+                              backgroundColor: Theme.of(context).primaryColor,
                             ),
                           ),
                           TextButton(
diff --git a/lib/widgets/desktop/desktop_new_ticket.dart b/lib/widgets/desktop/desktop_new_ticket.dart
index 3bec6a5..ec1e40f 100644
--- a/lib/widgets/desktop/desktop_new_ticket.dart
+++ b/lib/widgets/desktop/desktop_new_ticket.dart
@@ -154,7 +154,7 @@ class DesktopNewTicketState extends State<DesktopNewTicket> {
                                   fontSize: 18.0
                               ),
                               autofocus: true,
-                              validator: (String value) {
+                              validator: (String? value) {
                                 if (value.trim().isEmpty) {
                                   return S.of(context).this_field_is_required;
                                 }
@@ -210,7 +210,7 @@ class DesktopNewTicketState extends State<DesktopNewTicket> {
                         padding: EdgeInsets.only(top: 20.0, left: 16.0, right: 16.0, bottom: 20.0),
                         child: ElevatedButton(
                           style: ElevatedButton.styleFrom(
-                            primary: Theme.of(context).primaryColor,
+                            backgroundColor: Theme.of(context).primaryColor,
                           ),
                           child: Text(
                             S.of(context).login,
@@ -400,7 +400,7 @@ class DesktopNewTicketState extends State<DesktopNewTicket> {
             ElevatedButton(
               child: Text(S.of(context).yes_i_am_sure),
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               onPressed: () {
                 Navigator.of(context).pop();
diff --git a/lib/widgets/desktop/desktop_new_user.dart b/lib/widgets/desktop/desktop_new_user.dart
index c59905e..de7fbe1 100644
--- a/lib/widgets/desktop/desktop_new_user.dart
+++ b/lib/widgets/desktop/desktop_new_user.dart
@@ -80,7 +80,7 @@ class DesktopNewUserState extends State<DesktopNewUser> {
                         fontSize: 18.0
                     ),
                     autofocus: true,
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).mobile_or_email_is_required;
                       }
@@ -163,7 +163,7 @@ class DesktopNewUserState extends State<DesktopNewUser> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).verification_code_is_required;
                       }
@@ -196,7 +196,7 @@ class DesktopNewUserState extends State<DesktopNewUser> {
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).register,
diff --git a/lib/widgets/desktop/desktop_order_detail.dart b/lib/widgets/desktop/desktop_order_detail.dart
index 860738d..b4f6491 100644
--- a/lib/widgets/desktop/desktop_order_detail.dart
+++ b/lib/widgets/desktop/desktop_order_detail.dart
@@ -1177,7 +1177,7 @@ class DesktopOrderDetailState extends State<DesktopOrderDetail> {
                 S.of(context).no,
               ),
               style: TextButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               onPressed: () {
                 Navigator.of(context).pop();
diff --git a/lib/widgets/desktop/desktop_orders.dart b/lib/widgets/desktop/desktop_orders.dart
index e8d2d16..0ad46a7 100644
--- a/lib/widgets/desktop/desktop_orders.dart
+++ b/lib/widgets/desktop/desktop_orders.dart
@@ -263,7 +263,7 @@ class DesktopOrdersState extends State<DesktopOrders> with SingleTickerProviderS
                 ),
               ),
               style: ElevatedButton.styleFrom(
-                primary: Colors.redAccent,
+                backgroundColor: Colors.redAccent,
               ),
               onPressed: () {
                 Routes.router.navigateTo(context, '/paynow/${order.id}');
@@ -278,7 +278,7 @@ class DesktopOrdersState extends State<DesktopOrders> with SingleTickerProviderS
                 ),
               ),
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               onPressed: () {
                 Utils.orderAgain(context, order.cartInfo);
@@ -295,7 +295,7 @@ class DesktopOrdersState extends State<DesktopOrders> with SingleTickerProviderS
               ),
             ),
             style: ElevatedButton.styleFrom(
-              primary: Theme.of(context).primaryColor,
+              backgroundColor: Theme.of(context).primaryColor,
             ),
             onPressed: () {
               Utils.orderAgain(context, order.cartInfo);
diff --git a/lib/widgets/desktop/desktop_renew_license.dart b/lib/widgets/desktop/desktop_renew_license.dart
index 7e1d834..9eb2026 100644
--- a/lib/widgets/desktop/desktop_renew_license.dart
+++ b/lib/widgets/desktop/desktop_renew_license.dart
@@ -133,7 +133,7 @@ class DesktopRenewLicenseState extends State<DesktopRenewLicense> {
                       fontSize: 18.0
                   ),
                   autofocus: true,
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).please_enter_group_number;
                     }
diff --git a/lib/widgets/desktop/desktop_reset_password.dart b/lib/widgets/desktop/desktop_reset_password.dart
index a1ca1fc..0f3762d 100644
--- a/lib/widgets/desktop/desktop_reset_password.dart
+++ b/lib/widgets/desktop/desktop_reset_password.dart
@@ -92,7 +92,7 @@ class DesktopResetPasswordState extends State<DesktopResetPassword> {
                 style: TextStyle(
                     fontSize: 18.0
                 ),
-                validator: (String value) {
+                validator: (String? value) {
                   if (value.trim().isEmpty) {
                     return S.of(context).password_is_required;
                   }
@@ -146,7 +146,7 @@ class DesktopResetPasswordState extends State<DesktopResetPassword> {
                 style: TextStyle(
                     fontSize: 18.0
                 ),
-                validator: (String value) {
+                validator: (String? value) {
                   if (value.trim().isEmpty) {
                     return S.of(context).password_is_required;
                   }
@@ -179,7 +179,7 @@ class DesktopResetPasswordState extends State<DesktopResetPassword> {
                 alignment: Alignment.centerRight,
                 child: ElevatedButton(
                   style: ElevatedButton.styleFrom(
-                    primary: Theme.of(context).primaryColor,
+                    backgroundColor: Theme.of(context).primaryColor,
                   ),
                   child: Text(
                     S.of(context).submit,
diff --git a/lib/widgets/desktop/desktop_set_password.dart b/lib/widgets/desktop/desktop_set_password.dart
index af24f70..0c10c9d 100644
--- a/lib/widgets/desktop/desktop_set_password.dart
+++ b/lib/widgets/desktop/desktop_set_password.dart
@@ -92,7 +92,7 @@ class DesktopSetPasswordState extends State<DesktopSetPassword> {
                 style: TextStyle(
                     fontSize: 18.0
                 ),
-                validator: (String value) {
+                validator: (String? value) {
                   if (value.trim().isEmpty) {
                     return S.of(context).password_is_required;
                   }
@@ -146,7 +146,7 @@ class DesktopSetPasswordState extends State<DesktopSetPassword> {
                 style: TextStyle(
                     fontSize: 18.0
                 ),
-                validator: (String value) {
+                validator: (String? value) {
                   if (value.trim().isEmpty) {
                     return S.of(context).password_is_required;
                   }
@@ -179,7 +179,7 @@ class DesktopSetPasswordState extends State<DesktopSetPassword> {
                 alignment: Alignment.centerRight,
                 child: ElevatedButton(
                   style: ElevatedButton.styleFrom(
-                    primary: Theme.of(context).primaryColor,
+                    backgroundColor: Theme.of(context).primaryColor,
                   ),
                   child: Text(
                     S.of(context).submit,
diff --git a/lib/widgets/desktop/desktop_user_profile.dart b/lib/widgets/desktop/desktop_user_profile.dart
index 35d4d65..4e53ba2 100644
--- a/lib/widgets/desktop/desktop_user_profile.dart
+++ b/lib/widgets/desktop/desktop_user_profile.dart
@@ -424,7 +424,7 @@ class DesktopUserProfileState extends State<DesktopUserProfile> {
                       fontSize: 18.0
                   ),
                   autofocus: true,
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).nickname_is_required;
                     }
diff --git a/lib/widgets/desktop/desktop_view_ticket.dart b/lib/widgets/desktop/desktop_view_ticket.dart
index 00f9b30..54b6a5f 100644
--- a/lib/widgets/desktop/desktop_view_ticket.dart
+++ b/lib/widgets/desktop/desktop_view_ticket.dart
@@ -143,7 +143,7 @@ class DesktopViewTicketState extends State<DesktopViewTicket> {
                   fontSize: 18.0
               ),
               autofocus: false,
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.trim().isEmpty) {
                   return S.of(context).this_field_is_required;
                 }
@@ -194,7 +194,7 @@ class DesktopViewTicketState extends State<DesktopViewTicket> {
         padding: EdgeInsets.only(top: 20.0, left: 16.0, right: 16.0, bottom: 20.0),
         child: ElevatedButton(
           style: ElevatedButton.styleFrom(
-            primary: Theme.of(context).primaryColor,
+            backgroundColor: Theme.of(context).primaryColor,
           ),
           child: Text(
             S.of(context).reply,
@@ -644,7 +644,7 @@ class DesktopViewTicketState extends State<DesktopViewTicket> {
             ElevatedButton(
               child: Text(S.of(context).yes_i_am_sure),
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               onPressed: () {
                 Navigator.of(context).pop();
diff --git a/lib/widgets/general/add_remove_button.dart b/lib/widgets/general/add_remove_button.dart
index fe407bb..78cc8aa 100644
--- a/lib/widgets/general/add_remove_button.dart
+++ b/lib/widgets/general/add_remove_button.dart
@@ -125,7 +125,7 @@ class AddRemoveButtonState extends State<AddRemoveButton> {
           badgeColor: Colors.lightBlueAccent,
           child: ElevatedButton.icon(
             style: ElevatedButton.styleFrom(
-              primary: Colors.redAccent,
+              backgroundColor: Colors.redAccent,
               onPrimary: Colors.white,
               padding: EdgeInsets.only(left: 32, right: 32, top: 20, bottom: 20),
               elevation: 2.0,
@@ -154,7 +154,7 @@ class AddRemoveButtonState extends State<AddRemoveButton> {
       } else {
         return ElevatedButton.icon(
           style: ElevatedButton.styleFrom(
-            primary: Colors.redAccent,
+            backgroundColor: Colors.redAccent,
             padding: EdgeInsets.only(left: 32, right: 32, top: 20, bottom: 20),
             elevation: 2.0,
             shape: new RoundedRectangleBorder(
diff --git a/lib/widgets/general/download_item.dart b/lib/widgets/general/download_item.dart
index e9975c4..46afa5d 100644
--- a/lib/widgets/general/download_item.dart
+++ b/lib/widgets/general/download_item.dart
@@ -244,7 +244,7 @@ class DownloadItemState extends State<DownloadItem> {
     } else if (downloadUrl != null && downloadUrl.isNotEmpty) {
       return ElevatedButton(
         style: ElevatedButton.styleFrom(
-          primary: Theme.of(context).primaryColor,
+          backgroundColor: Theme.of(context).primaryColor,
           padding: EdgeInsets.all(8)
         ),
         child: Row(
diff --git a/lib/widgets/mobile/create_online_store_1.dart b/lib/widgets/mobile/create_online_store_1.dart
index 8abcaa8..b6424d0 100644
--- a/lib/widgets/mobile/create_online_store_1.dart
+++ b/lib/widgets/mobile/create_online_store_1.dart
@@ -230,7 +230,7 @@ class CreateOnlineStore1State extends State<CreateOnlineStore1> {
                         fontSize: 18.0
                     ),
                     autofocus: true,
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).domains_separated_comma;
                       }
diff --git a/lib/widgets/mobile/mobile_change_mobile_or_email.dart b/lib/widgets/mobile/mobile_change_mobile_or_email.dart
index 626ae79..8423325 100644
--- a/lib/widgets/mobile/mobile_change_mobile_or_email.dart
+++ b/lib/widgets/mobile/mobile_change_mobile_or_email.dart
@@ -93,7 +93,7 @@ class MobileChangeMobileOrEmailState extends State<MobileChangeMobileOrEmail> {
                         fontSize: 18.0
                     ),
                     autofocus: true,
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         if (widget.isMobile) {
                           return S
@@ -190,7 +190,7 @@ class MobileChangeMobileOrEmailState extends State<MobileChangeMobileOrEmail> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).verification_code_is_required;
                       }
@@ -223,7 +223,7 @@ class MobileChangeMobileOrEmailState extends State<MobileChangeMobileOrEmail> {
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).submit_to_change,
diff --git a/lib/widgets/mobile/mobile_change_password.dart b/lib/widgets/mobile/mobile_change_password.dart
index b3f2b0c..e892a74 100644
--- a/lib/widgets/mobile/mobile_change_password.dart
+++ b/lib/widgets/mobile/mobile_change_password.dart
@@ -87,7 +87,7 @@ class MobileChangePasswordState extends State<MobileChangePassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).current_password_is_required;
                       }
@@ -141,7 +141,7 @@ class MobileChangePasswordState extends State<MobileChangePassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).password_is_required;
                       }
@@ -195,7 +195,7 @@ class MobileChangePasswordState extends State<MobileChangePassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).password_is_required;
                       }
@@ -232,7 +232,7 @@ class MobileChangePasswordState extends State<MobileChangePassword> {
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).submit,
diff --git a/lib/widgets/mobile/mobile_checkout.dart b/lib/widgets/mobile/mobile_checkout.dart
index 1974db2..fdca378 100644
--- a/lib/widgets/mobile/mobile_checkout.dart
+++ b/lib/widgets/mobile/mobile_checkout.dart
@@ -114,7 +114,7 @@ class MobileCheckoutState extends State<MobileCheckout> with SingleTickerProvide
                 ),
                 ElevatedButton(
                   style: ElevatedButton.styleFrom(
-                    primary: Theme.of(context).primaryColor,
+                    backgroundColor: Theme.of(context).primaryColor,
                   ),
                   child: Text(
                     S.of(context).ok,
@@ -1632,7 +1632,7 @@ class MobileCheckoutState extends State<MobileCheckout> with SingleTickerProvide
                   ),
                   labelText: S.of(context).enter_coupon_code,
                 ),
-                validator: (String value) {
+                validator: (String? value) {
                   return null;
                 },
               ),
diff --git a/lib/widgets/mobile/mobile_coupons.dart b/lib/widgets/mobile/mobile_coupons.dart
index d893990..1016eaf 100644
--- a/lib/widgets/mobile/mobile_coupons.dart
+++ b/lib/widgets/mobile/mobile_coupons.dart
@@ -248,7 +248,7 @@ class MobileCouponsState extends State<MobileCoupons> {
           Container(
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
                 shape: RoundedRectangleBorder(
                   borderRadius: BorderRadius.circular(20),
                 ),
diff --git a/lib/widgets/mobile/mobile_edit_address.dart b/lib/widgets/mobile/mobile_edit_address.dart
index dbabd81..ab32977 100644
--- a/lib/widgets/mobile/mobile_edit_address.dart
+++ b/lib/widgets/mobile/mobile_edit_address.dart
@@ -109,7 +109,7 @@ class MobileEditAddressState extends State<MobileEditAddress> {
                         .of(context)
                         .contact_name,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value
                         .trim()
                         .isEmpty) {
@@ -164,7 +164,7 @@ class MobileEditAddressState extends State<MobileEditAddress> {
                         .of(context)
                         .mobile_phone_number,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value
                         .trim()
                         .isEmpty) {
@@ -196,7 +196,7 @@ class MobileEditAddressState extends State<MobileEditAddress> {
                         .of(context)
                         .street_line_1,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value
                         .trim()
                         .isEmpty) {
@@ -250,7 +250,7 @@ class MobileEditAddressState extends State<MobileEditAddress> {
                         .of(context)
                         .city,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value
                         .trim()
                         .isEmpty) {
@@ -320,7 +320,7 @@ class MobileEditAddressState extends State<MobileEditAddress> {
                         .of(context)
                         .postal_code,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value
                         .trim()
                         .isEmpty) {
@@ -365,7 +365,7 @@ class MobileEditAddressState extends State<MobileEditAddress> {
                         .of(context)
                         .email,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.isNotEmpty && !EmailValidator.validate(value)) {
                       return S
                           .of(context)
diff --git a/lib/widgets/mobile/mobile_forgot_password.dart b/lib/widgets/mobile/mobile_forgot_password.dart
index d2c16b3..3d295d1 100644
--- a/lib/widgets/mobile/mobile_forgot_password.dart
+++ b/lib/widgets/mobile/mobile_forgot_password.dart
@@ -90,7 +90,7 @@ class MobileForgotPasswordState extends State<MobileForgotPassword> {
                         fontSize: 18.0
                     ),
                     autofocus: true,
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).mobile_or_email_is_required;
                       }
@@ -173,7 +173,7 @@ class MobileForgotPasswordState extends State<MobileForgotPassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).verification_code_is_required;
                       }
@@ -206,7 +206,7 @@ class MobileForgotPasswordState extends State<MobileForgotPassword> {
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).verify,
diff --git a/lib/widgets/mobile/mobile_login.dart b/lib/widgets/mobile/mobile_login.dart
index f1b8a6e..bf94a37 100644
--- a/lib/widgets/mobile/mobile_login.dart
+++ b/lib/widgets/mobile/mobile_login.dart
@@ -103,7 +103,7 @@ class MobileLoginState extends State<MobileLogin> {
                       fontSize: 18.0
                   ),
                   autofocus: true,
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).this_field_is_required;
                     }
@@ -143,7 +143,7 @@ class MobileLoginState extends State<MobileLogin> {
                       fontSize: 18.0
                   ),
                   obscureText: passwordVisible,
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).password_is_required;
                     }
@@ -196,7 +196,7 @@ class MobileLoginState extends State<MobileLogin> {
             padding: EdgeInsets.only(top: 20.0, left: 16.0, right: 16.0, bottom: 20.0),
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).login,
diff --git a/lib/widgets/mobile/mobile_me.dart b/lib/widgets/mobile/mobile_me.dart
index a66f7a9..4bbb679 100644
--- a/lib/widgets/mobile/mobile_me.dart
+++ b/lib/widgets/mobile/mobile_me.dart
@@ -687,7 +687,7 @@ class MobileMeState extends State<MobileMe> {
                                       ),
                                       ElevatedButton(
                                         style: ElevatedButton.styleFrom(
-                                          primary: Theme.of(context).primaryColor,
+                                          backgroundColor: Theme.of(context).primaryColor,
                                           textStyle: TextStyle(
                                             color: Colors.white,
                                           ),
diff --git a/lib/widgets/mobile/mobile_new_address.dart b/lib/widgets/mobile/mobile_new_address.dart
index 5ffe425..c1a7d14 100644
--- a/lib/widgets/mobile/mobile_new_address.dart
+++ b/lib/widgets/mobile/mobile_new_address.dart
@@ -96,7 +96,7 @@ class MobileNewAddressState extends State<MobileNewAddress> {
                     ),
                     labelText: S.of(context).contact_name,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).contact_name_is_required;
                     }
@@ -140,7 +140,7 @@ class MobileNewAddressState extends State<MobileNewAddress> {
                     ),
                     labelText: S.of(context).mobile_phone_number,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).mobile_phone_number_is_required;
                     }
@@ -165,7 +165,7 @@ class MobileNewAddressState extends State<MobileNewAddress> {
                     ),
                     labelText: S.of(context).street_line_1,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).street_line_1_is_required;
                     }
@@ -209,7 +209,7 @@ class MobileNewAddressState extends State<MobileNewAddress> {
                     ),
                     labelText: S.of(context).city,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).city_is_required;
                     }
@@ -255,7 +255,7 @@ class MobileNewAddressState extends State<MobileNewAddress> {
                     ),
                     labelText: S.of(context).postal_code,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).postal_code_is_required;
                     }
@@ -290,7 +290,7 @@ class MobileNewAddressState extends State<MobileNewAddress> {
                     ),
                     labelText: S.of(context).email,
                   ),
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.isNotEmpty && !EmailValidator.validate(value)) {
                       return S.of(context).email_is_not_valid;
                     }
diff --git a/lib/widgets/mobile/mobile_new_comment.dart b/lib/widgets/mobile/mobile_new_comment.dart
index 8edc8f7..cb1a432 100644
--- a/lib/widgets/mobile/mobile_new_comment.dart
+++ b/lib/widgets/mobile/mobile_new_comment.dart
@@ -210,7 +210,7 @@ class MobileNewCommentState extends State<MobileNewComment> {
                               Navigator.of(context).pop();
                             },
                             style: TextButton.styleFrom(
-                              primary: Theme.of(context).primaryColor,
+                              backgroundColor: Theme.of(context).primaryColor,
                             ),
                           ),
                           TextButton(
diff --git a/lib/widgets/mobile/mobile_new_ticket.dart b/lib/widgets/mobile/mobile_new_ticket.dart
index 12ec0f4..75e5d31 100644
--- a/lib/widgets/mobile/mobile_new_ticket.dart
+++ b/lib/widgets/mobile/mobile_new_ticket.dart
@@ -110,7 +110,7 @@ class MobileNewTicketState extends State<MobileNewTicket> {
                       fontSize: 18.0
                   ),
                   autofocus: true,
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).this_field_is_required;
                     }
@@ -162,7 +162,7 @@ class MobileNewTicketState extends State<MobileNewTicket> {
             padding: EdgeInsets.only(top: 20.0, left: 16.0, right: 16.0, bottom: 20.0),
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).submit,
@@ -374,7 +374,7 @@ class MobileNewTicketState extends State<MobileNewTicket> {
             ElevatedButton(
               child: Text(S.of(context).yes_i_am_sure),
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               onPressed: () {
                 Navigator.of(context).pop();
diff --git a/lib/widgets/mobile/mobile_new_user.dart b/lib/widgets/mobile/mobile_new_user.dart
index c7ba78b..d4af700 100644
--- a/lib/widgets/mobile/mobile_new_user.dart
+++ b/lib/widgets/mobile/mobile_new_user.dart
@@ -87,7 +87,7 @@ class MobileNewUserState extends State<MobileNewUser> {
                         fontSize: 18.0
                     ),
                     autofocus: true,
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).mobile_or_email_is_required;
                       }
@@ -170,7 +170,7 @@ class MobileNewUserState extends State<MobileNewUser> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).verification_code_is_required;
                       }
@@ -203,7 +203,7 @@ class MobileNewUserState extends State<MobileNewUser> {
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).register,
diff --git a/lib/widgets/mobile/mobile_order_detail.dart b/lib/widgets/mobile/mobile_order_detail.dart
index 9020f9e..2a20590 100644
--- a/lib/widgets/mobile/mobile_order_detail.dart
+++ b/lib/widgets/mobile/mobile_order_detail.dart
@@ -1145,7 +1145,7 @@ class MobileOrderDetailState extends State<MobileOrderDetail> {
                 S.of(context).no,
               ),
               style: TextButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               onPressed: () {
                 Navigator.of(context).pop();
diff --git a/lib/widgets/mobile/mobile_orders.dart b/lib/widgets/mobile/mobile_orders.dart
index 64eb84f..544bc4d 100644
--- a/lib/widgets/mobile/mobile_orders.dart
+++ b/lib/widgets/mobile/mobile_orders.dart
@@ -234,7 +234,7 @@ class MobileOrdersState extends State<MobileOrders> with SingleTickerProviderSta
                 ),
               ),
               style: ElevatedButton.styleFrom(
-                primary: Colors.redAccent,
+                backgroundColor: Colors.redAccent,
               ),
               onPressed: () {
                 Routes.router.navigateTo(context, '/paynow/${order.id}');
@@ -249,7 +249,7 @@ class MobileOrdersState extends State<MobileOrders> with SingleTickerProviderSta
                 ),
               ),
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               onPressed: () {
                 Utils.orderAgain(context, order.cartInfo);
@@ -266,7 +266,7 @@ class MobileOrdersState extends State<MobileOrders> with SingleTickerProviderSta
               ),
             ),
             style: ElevatedButton.styleFrom(
-              primary: Theme.of(context).primaryColor,
+              backgroundColor: Theme.of(context).primaryColor,
             ),
             onPressed: () {
               Utils.orderAgain(context, order.cartInfo);
diff --git a/lib/widgets/mobile/mobile_renew_license.dart b/lib/widgets/mobile/mobile_renew_license.dart
index 2b5f7b5..b3e8936 100644
--- a/lib/widgets/mobile/mobile_renew_license.dart
+++ b/lib/widgets/mobile/mobile_renew_license.dart
@@ -96,7 +96,7 @@ class MobileRenewLicenseState extends State<MobileRenewLicense> {
               fontSize: 18.0
           ),
           autofocus: true,
-          validator: (String value) {
+          validator: (String? value) {
             if (value.trim().isEmpty) {
               return S.of(context).please_enter_group_number;
             }
diff --git a/lib/widgets/mobile/mobile_reset_password.dart b/lib/widgets/mobile/mobile_reset_password.dart
index b469376..976ab98 100644
--- a/lib/widgets/mobile/mobile_reset_password.dart
+++ b/lib/widgets/mobile/mobile_reset_password.dart
@@ -104,7 +104,7 @@ class MobileResetPasswordState extends State<MobileResetPassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).password_is_required;
                       }
@@ -158,7 +158,7 @@ class MobileResetPasswordState extends State<MobileResetPassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).password_is_required;
                       }
@@ -195,7 +195,7 @@ class MobileResetPasswordState extends State<MobileResetPassword> {
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).submit,
diff --git a/lib/widgets/mobile/mobile_set_password.dart b/lib/widgets/mobile/mobile_set_password.dart
index b79584d..4de71ea 100644
--- a/lib/widgets/mobile/mobile_set_password.dart
+++ b/lib/widgets/mobile/mobile_set_password.dart
@@ -105,7 +105,7 @@ class MobileSetPasswordState extends State<MobileSetPassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).password_is_required;
                       }
@@ -159,7 +159,7 @@ class MobileSetPasswordState extends State<MobileSetPassword> {
                     style: TextStyle(
                         fontSize: 18.0
                     ),
-                    validator: (String value) {
+                    validator: (String? value) {
                       if (value.trim().isEmpty) {
                         return S.of(context).password_is_required;
                       }
@@ -196,7 +196,7 @@ class MobileSetPasswordState extends State<MobileSetPassword> {
             alignment: Alignment.centerRight,
             child: ElevatedButton(
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               child: Text(
                 S.of(context).submit,
diff --git a/lib/widgets/mobile/mobile_user_profile.dart b/lib/widgets/mobile/mobile_user_profile.dart
index 1f0a26d..ec626fe 100644
--- a/lib/widgets/mobile/mobile_user_profile.dart
+++ b/lib/widgets/mobile/mobile_user_profile.dart
@@ -392,7 +392,7 @@ class MobileUserProfileState extends State<MobileUserProfile> {
                       fontSize: 18.0
                   ),
                   autofocus: true,
-                  validator: (String value) {
+                  validator: (String? value) {
                     if (value.trim().isEmpty) {
                       return S.of(context).nickname_is_required;
                     }
diff --git a/lib/widgets/mobile/mobile_view_ticket.dart b/lib/widgets/mobile/mobile_view_ticket.dart
index a98a319..0242890 100644
--- a/lib/widgets/mobile/mobile_view_ticket.dart
+++ b/lib/widgets/mobile/mobile_view_ticket.dart
@@ -293,7 +293,7 @@ class MobileViewTicketState extends State<MobileViewTicket> {
                   fontSize: 18.0
               ),
               autofocus: false,
-              validator: (String value) {
+              validator: (String? value) {
                 if (value.trim().isEmpty) {
                   return S.of(context).this_field_is_required;
                 }
@@ -338,7 +338,7 @@ class MobileViewTicketState extends State<MobileViewTicket> {
         padding: EdgeInsets.only(top: 20.0, left: 16.0, right: 16.0, bottom: 20.0),
         child: ElevatedButton(
           style: ElevatedButton.styleFrom(
-            primary: Theme.of(context).primaryColor,
+            backgroundColor: Theme.of(context).primaryColor,
           ),
           child: Text(
             S.of(context).reply,
@@ -641,7 +641,7 @@ class MobileViewTicketState extends State<MobileViewTicket> {
             ElevatedButton(
               child: Text(S.of(context).yes_i_am_sure),
               style: ElevatedButton.styleFrom(
-                primary: Theme.of(context).primaryColor,
+                backgroundColor: Theme.of(context).primaryColor,
               ),
               onPressed: () {
                 Navigator.of(context).pop();