Start to fix null safety migration errors

lib/ui/screens/group_sections/about_group_section.dart

@@ -13,8 +13,8 @@ class AboutGroupSection extends StatelessWidget {
   final AdvancedGroupInfo group;
 
   const AboutGroupSection({
-    Key key,
-    @required this.group,
+    Key? key,
+    required this.group,
   })  : assert(group != null),
         super(key: key);
 
@@ -25,7 +25,7 @@ class AboutGroupSection extends StatelessWidget {
           group.hasURL
               ? ListTile(
                   leading: Icon(Icons.link),
-                  title: Text(tr("URL")),
+                  title: Text(tr("URL")!),
                   subtitle: Text(group.url),
                   onTap: () => launch(group.url),
                 )
@@ -35,7 +35,7 @@ class AboutGroupSection extends StatelessWidget {
           group.hasDescription
               ? ListTile(
                   leading: Icon(Icons.note),
-                  title: Text(tr("Description")),
+                  title: Text(tr("Description")!),
                   subtitle: Text(group.description),
                 )
               : Container(),
@@ -44,64 +44,64 @@ class AboutGroupSection extends StatelessWidget {
           ListTile(
             leading: Icon(Icons.access_time),
             title: Text("Created"),
-            subtitle: Text(diffTimeFromNowToStr(group.timeCreate)),
+            subtitle: Text(diffTimeFromNowToStr(group.timeCreate!)!),
           ),
 
           // Number of members
           ListTile(
             leading: Icon(Icons.group),
-            title: Text(tr("Members")),
+            title: Text(tr("Members")!),
             subtitle: Text(
-                tr("%1% members", args: {"1": group.numberMembers.toString()})),
+                tr("%1% members", args: {"1": group.numberMembers.toString()})!),
           ),
 
           // Who can create posts
           ListTile(
             leading: Icon(Icons.add),
-            title: Text(tr("Who can create posts")),
+            title: Text(tr("Who can create posts")!),
             subtitle: Text(
                 group.postCreationLevel == GroupPostCreationLevel.MEMBERS
-                    ? tr("Every members")
-                    : tr("Only moderators and administrators")),
+                    ? tr("Every members")!
+                    : tr("Only moderators and administrators")!),
           ),
 
           // Registration process
           ListTile(
             leading: Icon(Icons.login),
-            title: Text(tr("Registration process")),
+            title: Text(tr("Registration process")!),
             subtitle: Text(group.registrationLevel ==
                     GroupRegistrationLevel.CLOSED
-                ? tr("On invitation only")
+                ? tr("On invitation only")!
                 : (group.registrationLevel == GroupRegistrationLevel.MODERATED
-                    ? tr("A moderator has to approve requests")
-                    : tr("Anyone can join the group without approval"))),
+                    ? tr("A moderator has to approve requests")!
+                    : tr("Anyone can join the group without approval")!)),
           ),
 
           // Group visibility
           ListTile(
             leading: Icon(Icons.remove_red_eye),
-            title: Text(tr("Visibility")),
+            title: Text(tr("Visibility")!),
             subtitle: Text(group.visibilityLevel == GroupVisibilityLevel.SECRETE
-                ? tr("Secrete group")
+                ? tr("Secrete group")!
                 : (group.visibilityLevel == GroupVisibilityLevel.PRIVATE
-                    ? tr("Private group")
-                    : tr("Open group"))),
+                    ? tr("Private group")!
+                    : tr("Open group")!)),
           ),
 
           // Group members visibility
           ListTile(
             leading: Icon(Icons.remove_red_eye),
-            title: Text(tr("Members list visibility")),
+            title: Text(tr("Members list visibility")!),
             subtitle:
-                Text(group.isMembersListPublic ? tr("Public") : tr("Private")),
+                Text(group.isMembersListPublic! ? tr("Public")! : tr("Private")!),
           ),
 
           group.isForezGroup
               ? // Group members visibility
               ListTile(
                   leading: Icon(Icons.info_outline),
-                  title: Text(tr("Forez group")),
-                  subtitle: Text(tr("Forez special features enabled")),
+                  title: Text(tr("Forez group")!),
+                  subtitle: Text(tr("Forez special features enabled")!),
                 )
               : Container(),
         ],

lib/ui/screens/group_sections/forez_presence_section.dart

@@ -16,8 +16,8 @@ class ForezPresenceSection extends StatefulWidget {
   final int groupID;
 
   const ForezPresenceSection({
-    Key key,
-    @required this.groupID,
+    Key? key,
+    required this.groupID,
   })  : assert(groupID != null),
         super(key: key);
 
@@ -26,17 +26,17 @@ class ForezPresenceSection extends StatefulWidget {
 }
 
 class _ForezPresenceSectionState extends State<ForezPresenceSection> {
-  PresenceSet _presences;
-  UsersList _users;
+  PresenceSet? _presences;
+  late UsersList _users;
   DateTime _currentDay = DateTime.now();
 
-  List<int> get _currentListOfUsers => _presences.getUsersAtDate(_currentDay);
+  List<int> get _currentListOfUsers => _presences!.getUsersAtDate(_currentDay);
 
   Future<void> _refresh() async {
     await ForezPresenceHelper.refreshCache(widget.groupID);
 
     _presences = await ForezPresenceHelper.getAll(widget.groupID);
-    _users = await UsersHelper().getList(_presences.usersID);
+    _users = await UsersHelper().getList(_presences!.usersID);
   }
 
   @override
@@ -71,7 +71,7 @@ class _ForezPresenceSectionState extends State<ForezPresenceSection> {
   }
 
   Widget _buildCalendar() => PresenceCalendarWidget(
-        presenceSet: _presences,
+        presenceSet: _presences!,
         mode: CalendarDisplayMode.MULTIPLE_USERS,
         selectedDay: _currentDay,
         onDayClicked: _selectDay,

lib/ui/screens/group_sections/group_conversation_section.dart

@@ -12,8 +12,8 @@ class GroupConversationSection extends StatelessWidget {
   final Conversation conv;
 
   const GroupConversationSection({
-    Key key,
-    @required this.conv,
+    Key? key,
+    required this.conv,
   })  : assert(conv != null),
         super(key: key);
 
@@ -21,7 +21,7 @@ class GroupConversationSection extends StatelessWidget {
   Widget build(BuildContext context) => Stack(
         children: [
           ConversationScreen(
-            conversationID: conv.id,
+            conversationID: conv.id!,
           ),
           Positioned(
             right: 1.0,
@@ -31,12 +31,12 @@ class GroupConversationSection extends StatelessWidget {
                     ? IconButton(
                         icon: Icon(Icons.phone),
                         onPressed: () =>
-                            MainController.of(context).startCall(conv.id),
+                            MainController.of(context)!.startCall(conv.id!),
                       )
                     : Container(),
                 IconButton(
                   icon: Icon(Icons.settings),
-                  onPressed: () => MainController.of(context)
+                  onPressed: () => MainController.of(context)!
                       .openConversationSettingsRoute(conv),
                 ),
               ],

lib/ui/screens/group_sections/group_members_screen.dart

@@ -21,7 +21,7 @@ import 'package:flutter/material.dart';
 class GroupMembersSection extends StatefulWidget {
   final int groupID;
 
-  const GroupMembersSection({Key key, this.groupID})
+  const GroupMembersSection({Key? key, required this.groupID})
       : assert(groupID != null),
         super(key: key);
 
@@ -31,9 +31,9 @@ class GroupMembersSection extends StatefulWidget {
 
 class _GroupMembersSectionState extends State<GroupMembersSection> {
   final _key = GlobalKey<AsyncScreenWidgetState>();
-  Group _group;
-  GroupMembersList _members;
-  UsersList _users;
+  late Group _group;
+  late GroupMembersList _members;
+  late UsersList _users;
 
   Future<void> _refresh() async {
     final group = await GroupsHelper().getSingle(widget.groupID, force: true);
@@ -50,7 +50,7 @@ class _GroupMembersSectionState extends State<GroupMembersSection> {
         key: _key,
         onReload: _refresh,
         onBuild: _buildBodyContent,
-        errorMessage: tr("Could not load the list of members of this group!"),
+        errorMessage: tr("Could not load the list of members of this group!")!,
         showOldDataWhileUpdating: true,
       );
 
@@ -70,7 +70,7 @@ class _GroupMembersSectionState extends State<GroupMembersSection> {
       group: _group,
       membership: membership,
       user: user,
-      onUpdated: () => _key.currentState.refresh(),
+      onUpdated: () => _key.currentState!.refresh(),
     );
   }
 
@@ -93,40 +93,40 @@ class _GroupMembersSectionState extends State<GroupMembersSection> {
       await GroupsHelper.sendInvitation(widget.groupID, userID);
     } catch (e, s) {
       print("Could not invite a user! $e\n$s");
-      showSimpleSnack(context, tr("Could not invite a user!"));
+      showSimpleSnack(context, tr("Could not invite a user!")!);
     }
 
-    _key.currentState.refresh();
+    _key.currentState!.refresh();
   }
 }
 
 List<MultiChoiceEntry<GroupMembershipLevel>> get _membershipLevels => [
       MultiChoiceEntry(
           id: GroupMembershipLevel.ADMINISTRATOR,
-          title: tr("Administrator"),
+          title: tr("Administrator")!,
           subtitle: tr("Can change members privileges and group settings")),
       MultiChoiceEntry(
           id: GroupMembershipLevel.MODERATOR,
-          title: tr("Moderator"),
+          title: tr("Moderator")!,
           subtitle: tr(
               "Can always create posts, invite users and respond to membership request")),
       MultiChoiceEntry(
           id: GroupMembershipLevel.MEMBER,
-          title: tr("Member"),
+          title: tr("Member")!,
           subtitle: tr("Can access to all group posts")),
       MultiChoiceEntry(
         id: GroupMembershipLevel.PENDING,
-        title: tr("Requested"),
+        title: tr("Requested")!,
         hidden: true,
       ),
       MultiChoiceEntry(
         id: GroupMembershipLevel.INVITED,
-        title: tr("Invited"),
+        title: tr("Invited")!,
         hidden: true,
       ),
       MultiChoiceEntry(
         id: GroupMembershipLevel.VISITOR,
-        title: tr("Visitor"),
+        title: tr("Visitor")!,
         hidden: true,
       ),
     ];
@@ -138,11 +138,11 @@ class _GroupMembershipTile extends StatefulWidget {
   final void Function() onUpdated;
 
   const _GroupMembershipTile({
-    Key key,
-    @required this.group,
-    @required this.membership,
-    @required this.user,
-    @required this.onUpdated,
+    Key? key,
+    required this.group,
+    required this.membership,
+    required this.user,
+    required this.onUpdated,
   })  : assert(group != null),
         assert(membership != null),
         assert(user != null),
@@ -176,7 +176,7 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
     );
   }
 
-  Widget _buildTrailing() {
+  Widget? _buildTrailing() {
     switch (widget.membership.level) {
       case GroupMembershipLevel.ADMINISTRATOR:
       case GroupMembershipLevel.MODERATOR:
@@ -205,14 +205,14 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
       itemBuilder: (c) => [
         // Change membership level
         PopupMenuItem(
-          child: Text(tr("Change level")),
+          child: Text(tr("Change level")!),
           enabled: !_isCurrentUser && widget.group.isAdmin,
           value: _MemberMenuOptions.CHANGE_LEVEL,
         ),
 
         // Remove membership
         PopupMenuItem(
-          child: Text(tr("Remove")),
+          child: Text(tr("Remove")!),
           value: _MemberMenuOptions.DELETE,
           enabled: !_isCurrentUser,
         ),
@@ -247,7 +247,7 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
       await GroupsHelper.setNewLevel(groupID, memberID, newLevel);
     } catch (e, s) {
       print("Could not change group membership level! $e\n$s");
-      showSimpleSnack(context, tr("Could not change group membership level!"));
+      showSimpleSnack(context, tr("Could not change group membership level!")!);
     }
 
     widget.onUpdated();
@@ -263,7 +263,7 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
       await GroupsHelper.removeMemberFromGroup(groupID, memberID);
     } catch (e, s) {
       print("Could not remove membership! $e\n$s");
-      showSimpleSnack(context, tr("Could not remove this membership!"));
+      showSimpleSnack(context, tr("Could not remove this membership!")!);
     }
 
     widget.onUpdated();
@@ -272,7 +272,7 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
   Widget _buildInvitedCase() {
     return MaterialButton(
       onPressed: _cancelMembership,
-      child: Text(tr("Cancel").toUpperCase()),
+      child: Text(tr("Cancel")!.toUpperCase()),
       textColor: Colors.red,
     );
   }
@@ -282,7 +282,7 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
       await GroupsHelper.cancelInvitation(groupID, memberID);
     } catch (e, s) {
       print("Could not cancel invitation! $e\n$s");
-      showSimpleSnack(context, tr("Could not cancel invitation!"));
+      showSimpleSnack(context, tr("Could not cancel invitation!")!);
     }
 
     widget.onUpdated();
@@ -294,12 +294,12 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
       children: <Widget>[
         MaterialButton(
           onPressed: () => _respondRequest(false),
-          child: Text(tr("Reject").toUpperCase()),
+          child: Text(tr("Reject")!.toUpperCase()),
           textColor: Colors.red,
         ),
         MaterialButton(
           onPressed: () => _respondRequest(true),
-          child: Text(tr("Accept").toUpperCase()),
+          child: Text(tr("Accept")!.toUpperCase()),
           textColor: Colors.green,
         )
       ],
@@ -311,7 +311,7 @@ class __GroupMembershipTileState extends State<_GroupMembershipTile> {
       await GroupsHelper.respondRequest(groupID, memberID, accept);
     } catch (e, s) {
       print("Could not respond to membership request! $e\n$s");
-      showSimpleSnack(context, tr("Could not respond to membership request!"));
+      showSimpleSnack(context, tr("Could not respond to membership request!")!);
     }
 
     widget.onUpdated();

lib/ui/screens/group_sections/group_posts_section.dart

@@ -12,8 +12,8 @@ class GroupPostsSection extends StatefulWidget {
   final AdvancedGroupInfo group;
 
   const GroupPostsSection({
-    Key key,
-    @required this.group,
+    Key? key,
+    required this.group,
   })  : assert(group != null),
         super(key: key);
 
@@ -31,7 +31,7 @@ class _GroupPostsSectionState extends State<GroupPostsSection> {
     return PostCreateFormWidget(
       postTarget: PostTarget.GROUP_PAGE,
       targetID: widget.group.id,
-      onCreated: () => _postsKey.currentState.loadPostsList(getOlder: false),
+      onCreated: () => _postsKey.currentState!.loadPostsList(getOlder: false),
     );
   }