update

lib/pages/faq/faq_detail_page.dart

@@ -13,14 +13,14 @@ import 'package:provider/provider.dart';
 
 class FAQDetailPage extends StatefulWidget {
   final FAQ faq;
-  const FAQDetailPage({this.faq});
+  const FAQDetailPage({required this.faq});
   @override
   _FAQDetailPageState createState() => _FAQDetailPageState();
 }
 
 class _FAQDetailPageState extends State<FAQDetailPage> {
   bool _isLoading = false;
-  FAQ faq;
+  FAQ faq = new FAQ();
 
   intState() {
     super.initState();

lib/pages/faq/faq_edit_page.dart

@@ -10,13 +10,12 @@ import 'package:fcs/pages/widgets/local_text.dart';
 import 'package:fcs/pages/widgets/progress.dart';
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter_icons/flutter_icons.dart';
 import 'package:provider/provider.dart';
 
 const info = "Select additional page";
 
 class FAQEditor extends StatefulWidget {
-  final FAQ faq;
+  final FAQ? faq;
   const FAQEditor({this.faq});
   @override
   _FAQEditorState createState() => _FAQEditorState();
@@ -35,20 +34,22 @@ class _FAQEditorState extends State<FAQEditor> {
   bool _isLoading = false;
   bool _isNew = false;
   String _pageLink = info;
+  FAQ _faq = new FAQ();
 
   @override
   void initState() {
     super.initState();
     _isNew = widget.faq == null;
     if (widget.faq != null) {
-      _sn.text = widget.faq.sn.toString();
-      _engQ.text = widget.faq.questionEng;
-      _mmQ.text = widget.faq.questionMm;
-      _engA.text = widget.faq.answerEng;
-      _mmA.text = widget.faq.answerMm;
-      _pageLabelEng.text = widget.faq.pageLinkLabelEng;
-      _pageLabelMm.text = widget.faq.pageLinkLabelMm;
-      _pageLink = widget.faq.pageLink;
+      _faq = widget.faq!;
+      _sn.text = _faq.sn.toString();
+      _engQ.text = _faq.questionEng;
+      _mmQ.text = _faq.questionMm;
+      _engA.text = _faq.answerEng;
+      _mmA.text = _faq.answerMm;
+      _pageLabelEng.text = _faq.pageLinkLabelEng;
+      _pageLabelMm.text = _faq.pageLinkLabelMm;
+      _pageLink = _faq.pageLink;
     }
   }
 
@@ -89,7 +90,8 @@ class _FAQEditorState extends State<FAQEditor> {
         height: 2,
         color: primaryColor,
       ),
-      onChanged: (String newValue) {
+      onChanged: (String? newValue) {
+        if(newValue != null)
         setState(() {
           _pageLink = newValue;
         });
@@ -211,7 +213,7 @@ class _FAQEditorState extends State<FAQEditor> {
       if (_isNew) {
         await faqModel.addFAQ(_faq);
       } else {
-        _faq.id = widget.faq.id;
+        _faq.id = this._faq.id;
         await faqModel.updateFAQ(_faq);
       }
       Navigator.pop(context);
@@ -234,7 +236,7 @@ class _FAQEditorState extends State<FAQEditor> {
     });
     try {
       FAQModel faqModel = Provider.of<FAQModel>(context, listen: false);
-      await faqModel.deleteFAQ(widget.faq);
+      await faqModel.deleteFAQ(this._faq);
       Navigator.pop(context);
     } catch (e) {
       showMsgDialog(context, "Error", e.toString());

lib/pages/faq/faq_list_page.dart

@@ -1,14 +1,12 @@
 import 'package:fcs/domain/constants.dart';
 import 'package:fcs/domain/entities/faq.dart';
 import 'package:fcs/helpers/theme.dart';
-import 'package:fcs/localization/app_translations.dart';
 import 'package:fcs/pages/buying_instruction/buying_online.dart';
 import 'package:fcs/pages/faq/faq_edit_page.dart';
 import 'package:fcs/pages/main/model/language_model.dart';
 import 'package:fcs/pages/main/model/main_model.dart';
 import 'package:fcs/pages/payment_methods/payment_method_page.dart';
 import 'package:fcs/pages/rates/shipment_rates.dart';
-import 'package:fcs/pages/widgets/bottom_up_page_route.dart';
 import 'package:fcs/pages/widgets/fcs_expansion_tile.dart';
 import 'package:fcs/pages/widgets/local_text.dart';
 import 'package:flutter/cupertino.dart';
@@ -26,8 +24,8 @@ class FAQListPage extends StatefulWidget {
 
 class _FAQListPageState extends State<FAQListPage>
     with SingleTickerProviderStateMixin {
-  AnimationController _controller;
-  Animation<double> _iconTurns;
+  AnimationController? _controller;
+  Animation<double>? _iconTurns;
 
   @override
   void initState() {
@@ -35,7 +33,7 @@ class _FAQListPageState extends State<FAQListPage>
     _controller = AnimationController(duration: _kExpand, vsync: this);
     var _halfTween = Tween<double>(begin: 0.0, end: 0.5);
     var _easeInTween = CurveTween(curve: Curves.easeIn);
-    _iconTurns = _controller.drive(_halfTween.chain(_easeInTween));
+    _iconTurns = _controller?.drive(_halfTween.chain(_easeInTween));
   }
 
   @override
@@ -139,7 +137,7 @@ class _FAQListPageState extends State<FAQListPage>
     );
   }
 
-  Widget _pageLink(String linkPage, String text) {
+  Widget _pageLink(String? linkPage, String? text) {
     return linkPage == null || linkPage == "" || text == null || text == ""
         ? Container()
         : Row(