refactor: Make widgets null safe

lib/pages/search/search.dart

@@ -45,7 +45,7 @@ class SearchController extends State<Search> {
     showModalBottomSheet(
       context: context,
       builder: (c) => PublicRoomBottomSheet(
-        roomAlias: room.canonicalAlias,
+        roomAlias: room.canonicalAlias ?? room.roomId,
         outerContext: context,
         chunk: room,
       ),

lib/widgets/content_banner.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'package:flutter/material.dart';
 
 import 'package:cached_network_image/cached_network_image.dart';
@@ -10,8 +12,8 @@ class ContentBanner extends StatelessWidget {
   final double height;
   final IconData defaultIcon;
   final bool loading;
-  final Function onEdit;
-  final Client client;
+  final void Function()? onEdit;
+  final Client? client;
   final double opacity;
 
   const ContentBanner(this.mxContent,
@@ -21,7 +23,7 @@ class ContentBanner extends StatelessWidget {
       this.onEdit,
       this.client,
       this.opacity = 0.75,
-      Key key})
+      Key? key})
       : super(key: key);
 
   @override
@@ -29,7 +31,8 @@ class ContentBanner extends StatelessWidget {
     final mediaQuery = MediaQuery.of(context);
     final bannerSize =
         (mediaQuery.size.width * mediaQuery.devicePixelRatio).toInt();
-    final src = mxContent?.getThumbnail(
+    final onEdit = this.onEdit;
+    final src = mxContent.getThumbnail(
       client ?? Matrix.of(context).client,
       width: bannerSize,
       height: bannerSize,
@@ -51,14 +54,13 @@ class ContentBanner extends StatelessWidget {
             bottom: 0,
             child: Opacity(
               opacity: opacity,
-              child:
-                  (!loading && mxContent != null && mxContent.host.isNotEmpty)
-                      ? CachedNetworkImage(
-                          imageUrl: src.toString(),
-                          height: 300,
-                          fit: BoxFit.cover,
-                        )
-                      : Icon(defaultIcon, size: 200),
+              child: (!loading && mxContent.host.isNotEmpty)
+                  ? CachedNetworkImage(
+                      imageUrl: src.toString(),
+                      height: 300,
+                      fit: BoxFit.cover,
+                    )
+                  : Icon(defaultIcon, size: 200),
             ),
           ),
           if (onEdit != null)
@@ -69,7 +71,7 @@ class ContentBanner extends StatelessWidget {
                 mini: true,
                 onPressed: onEdit,
                 backgroundColor: Theme.of(context).backgroundColor,
-                foregroundColor: Theme.of(context).textTheme.bodyText1.color,
+                foregroundColor: Theme.of(context).textTheme.bodyText1?.color,
                 child: const Icon(Icons.camera_alt_outlined),
               ),
             ),

lib/widgets/default_app_bar_search_field.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'package:flutter/material.dart';
 
 import 'package:flutter_gen/gen_l10n/l10n.dart';
@@ -5,22 +7,22 @@ import 'package:flutter_gen/gen_l10n/l10n.dart';
 import '../config/app_config.dart';
 
 class DefaultAppBarSearchField extends StatefulWidget {
-  final TextEditingController searchController;
-  final void Function(String) onChanged;
-  final void Function(String) onSubmit;
-  final Widget suffix;
+  final TextEditingController? searchController;
+  final void Function(String)? onChanged;
+  final void Function(String)? onSubmit;
+  final Widget? suffix;
   final bool autofocus;
-  final String prefixText;
-  final String hintText;
-  final String labelText;
-  final EdgeInsets padding;
+  final String? prefixText;
+  final String? hintText;
+  final String? labelText;
+  final EdgeInsets? padding;
   final bool readOnly;
-  final Widget prefixIcon;
+  final Widget? prefixIcon;
   final bool unfocusOnClear;
   final bool autocorrect;
 
   const DefaultAppBarSearchField({
-    Key key,
+    Key? key,
     this.searchController,
     this.onChanged,
     this.onSubmit,
@@ -42,14 +44,14 @@ class DefaultAppBarSearchField extends StatefulWidget {
 }
 
 class DefaultAppBarSearchFieldState extends State<DefaultAppBarSearchField> {
-  TextEditingController _searchController;
+  late final TextEditingController _searchController;
   bool _lastTextWasEmpty = false;
   final FocusNode _focusNode = FocusNode();
 
   void requestFocus() => _focusNode.requestFocus();
 
   void _updateSearchController() {
-    final thisTextIsEmpty = _searchController.text?.isEmpty ?? false;
+    final thisTextIsEmpty = _searchController.text.isEmpty;
     if (_lastTextWasEmpty != thisTextIsEmpty) {
       setState(() => _lastTextWasEmpty = thisTextIsEmpty);
     }
@@ -61,7 +63,7 @@ class DefaultAppBarSearchFieldState extends State<DefaultAppBarSearchField> {
     _searchController = widget.searchController ?? TextEditingController();
     // we need to remove the listener in the dispose method, so we need a reference to the callback
     _searchController.addListener(_updateSearchController);
-    _focusNode.addListener(() => setState(() => null));
+    _focusNode.addListener(() => setState(() {}));
   }
 
   @override
@@ -108,9 +110,9 @@ class DefaultAppBarSearchFieldState extends State<DefaultAppBarSearchField> {
           suffixIcon: !widget.readOnly &&
                   (_focusNode.hasFocus ||
                       (widget.suffix == null &&
-                          (_searchController.text?.isNotEmpty ?? false)))
+                          (_searchController.text.isNotEmpty)))
               ? IconButton(
-                  tooltip: L10n.of(context).clearText,
+                  tooltip: L10n.of(context)!.clearText,
                   icon: const Icon(Icons.backspace_outlined),
                   onPressed: () {
                     _searchController.clear();

lib/widgets/local_notifications_extension.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'dart:io';
 
 import 'package:flutter/foundation.dart';
@@ -18,14 +20,18 @@ extension LocalNotificationsExtension on MatrixState {
     final roomId = eventUpdate.roomID;
     if (webHasFocus && activeRoomId == roomId) return;
     final room = client.getRoomById(roomId);
+    if (room == null) {
+      Logs().w('Can not display notification for unknown room $roomId');
+      return;
+    }
     if (room.notificationCount == 0) return;
     final event = Event.fromJson(eventUpdate.content, room);
     final title =
-        room.getLocalizedDisplayname(MatrixLocals(L10n.of(widget.context)));
+        room.getLocalizedDisplayname(MatrixLocals(L10n.of(widget.context)!));
     final body = event.getLocalizedBody(
-      MatrixLocals(L10n.of(widget.context)),
+      MatrixLocals(L10n.of(widget.context)!),
       withSenderNamePrefix:
-          !room.isDirectChat || room.lastEvent.senderId == client.userID,
+          !room.isDirectChat || room.lastEvent?.senderId == client.userID,
       plaintextBody: true,
       hideReply: true,
       hideEdit: true,
@@ -51,7 +57,7 @@ extension LocalNotificationsExtension on MatrixState {
         width: 56,
         height: 56,
       );
-      File appIconFile;
+      File? appIconFile;
       if (appIconUrl != null) {
         final tempDirectory = await getApplicationSupportDirectory();
         final avatarDirectory =
@@ -68,15 +74,15 @@ extension LocalNotificationsExtension on MatrixState {
         body: body,
         replacesId: linuxNotificationIds[roomId] ?? 0,
         appName: AppConfig.applicationName,
-        appIcon: appIconFile.path,
+        appIcon: appIconFile?.path ?? '',
         actions: [
           NotificationAction(
             DesktopNotificationActions.dismiss.name,
-            L10n.of(widget.context).dismiss,
+            L10n.of(widget.context)!.dismiss,
           ),
           NotificationAction(
             DesktopNotificationActions.seen.name,
-            L10n.of(widget.context).markAsRead,
+            L10n.of(widget.context)!.markAsRead,
           ),
         ],
         hints: [

lib/widgets/lock_screen.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'package:flutter/material.dart';
 
 import 'package:flutter_app_lock/flutter_app_lock.dart';
@@ -12,7 +14,7 @@ import 'package:fluffychat/config/themes.dart';
 import 'layouts/one_page_card.dart';
 
 class LockScreen extends StatefulWidget {
-  const LockScreen({Key key}) : super(key: key);
+  const LockScreen({Key? key}) : super(key: key);
 
   @override
   _LockScreenState createState() => _LockScreenState();
@@ -37,7 +39,7 @@ class _LockScreenState extends State<LockScreen> {
               automaticallyImplyLeading: false,
               elevation: 0,
               centerTitle: true,
-              title: Text(L10n.of(context).pleaseEnterYourPin),
+              title: Text(L10n.of(context)!.pleaseEnterYourPin),
               backgroundColor: Colors.transparent,
             ),
             extendBodyBehindAppBar: true,
@@ -78,7 +80,7 @@ class _LockScreenState extends State<LockScreen> {
                               prefs.getString(SettingKeys.appLockKey))
                           : const FlutterSecureStorage()
                               .read(key: SettingKeys.appLockKey))) {
-                    AppLock.of(context).didUnlock();
+                    AppLock.of(context)!.didUnlock();
                   } else {
                     _textEditingController.clear();
                     setState(() => _wrongInput = true);

lib/widgets/log_view.dart

@@ -1,9 +1,11 @@
+//@dart=2.12
+
 import 'package:flutter/material.dart';
 
 import 'package:matrix/matrix.dart';
 
 class LogViewer extends StatefulWidget {
-  const LogViewer({Key key}) : super(key: key);
+  const LogViewer({Key? key}) : super(key: key);
 
   @override
   _LogViewerState createState() => _LogViewerState();

lib/widgets/permission_slider_dialog.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
 
@@ -8,11 +10,11 @@ import 'package:fluffychat/widgets/adaptive_flat_button.dart';
 
 class PermissionSliderDialog extends StatefulWidget {
   const PermissionSliderDialog({
-    Key key,
+    Key? key,
     this.initialPermission = 0,
   }) : super(key: key);
 
-  Future<int> show(BuildContext context) => PlatformInfos.isCupertinoStyle
+  Future<int?> show(BuildContext context) => PlatformInfos.isCupertinoStyle
       ? showCupertinoDialog<int>(
           context: context,
           builder: (context) => this,
@@ -30,7 +32,7 @@ class PermissionSliderDialog extends StatefulWidget {
 }
 
 class _PermissionSliderDialogState extends State<PermissionSliderDialog> {
-  int _permission;
+  late int _permission;
   @override
   void initState() {
     _permission = widget.initialPermission;
@@ -40,7 +42,7 @@ class _PermissionSliderDialogState extends State<PermissionSliderDialog> {
   @override
   Widget build(BuildContext context) {
     final title = Text(
-      L10n.of(context).setPermissionsLevel,
+      L10n.of(context)!.setPermissionsLevel,
       textAlign: TextAlign.center,
     );
     final content = Column(
@@ -48,9 +50,9 @@ class _PermissionSliderDialogState extends State<PermissionSliderDialog> {
       children: [
         Text('Level: ' +
             (_permission == 100
-                ? '$_permission (${L10n.of(context).admin})'
+                ? '$_permission (${L10n.of(context)!.admin})'
                 : _permission >= 50
-                    ? '$_permission (${L10n.of(context).moderator})'
+                    ? '$_permission (${L10n.of(context)!.moderator})'
                     : _permission.toString())),
         SizedBox(
           height: 56,
@@ -65,12 +67,12 @@ class _PermissionSliderDialogState extends State<PermissionSliderDialog> {
     );
     final buttons = [
       AdaptiveFlatButton(
-        label: L10n.of(context).cancel,
+        label: L10n.of(context)!.cancel,
         onPressed: () =>
             Navigator.of(context, rootNavigator: false).pop<int>(null),
       ),
       AdaptiveFlatButton(
-        label: L10n.of(context).confirm,
+        label: L10n.of(context)!.confirm,
         onPressed: () =>
             Navigator.of(context, rootNavigator: false).pop<int>(_permission),
       ),

lib/widgets/profile_bottom_sheet.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'dart:math';
 
 import 'package:flutter/material.dart';
@@ -16,9 +18,9 @@ class ProfileBottomSheet extends StatelessWidget {
   final String userId;
   final BuildContext outerContext;
   const ProfileBottomSheet({
-    @required this.userId,
-    @required this.outerContext,
-    Key key,
+    required this.userId,
+    required this.outerContext,
+    Key? key,
   }) : super(key: key);
 
   void _startDirectChat(BuildContext context) async {
@@ -28,7 +30,7 @@ class ProfileBottomSheet extends StatelessWidget {
       future: () => client.startDirectChat(userId),
     );
     if (result.error == null) {
-      VRouter.of(context).toSegments(['rooms', result.result]);
+      VRouter.of(context).toSegments(['rooms', result.result!]);
       Navigator.of(context, rootNavigator: false).pop();
       return;
     }
@@ -52,7 +54,7 @@ class ProfileBottomSheet extends StatelessWidget {
                 leading: IconButton(
                   icon: const Icon(Icons.arrow_downward_outlined),
                   onPressed: Navigator.of(context, rootNavigator: false).pop,
-                  tooltip: L10n.of(context).close,
+                  tooltip: L10n.of(context)!.close,
                 ),
               ),
               body: FutureBuilder<Profile>(
@@ -69,19 +71,20 @@ class ProfileBottomSheet extends StatelessWidget {
                                   alignment: Alignment.center,
                                   color: Theme.of(context).secondaryHeaderColor,
                                   child: snapshot.hasError
-                                      ? Text(snapshot.error
+                                      ? Text(snapshot.error!
                                           .toLocalizedString(context))
                                       : const CircularProgressIndicator
                                           .adaptive(strokeWidth: 2),
                                 )
                               : ContentBanner(
-                                  profile.avatarUrl,
+                                  profile.avatarUrl!,
                                   defaultIcon: Icons.person_outline,
                                   client: Matrix.of(context).client,
                                 ),
                         ),
                         ListTile(
-                          title: Text(profile?.displayName ?? userId.localpart),
+                          title: Text(
+                              profile?.displayName ?? userId.localpart ?? ''),
                           subtitle: Text(userId),
                           trailing: const Icon(Icons.account_box_outlined),
                         ),
@@ -90,7 +93,7 @@ class ProfileBottomSheet extends StatelessWidget {
                           padding: const EdgeInsets.all(12),
                           child: ElevatedButton.icon(
                             onPressed: () => _startDirectChat(context),
-                            label: Text(L10n.of(context).newChat),
+                            label: Text(L10n.of(context)!.newChat),
                             icon: const Icon(Icons.send_outlined),
                           ),
                         ),

lib/widgets/public_room_bottom_sheet.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'dart:math';
 
 import 'package:flutter/material.dart';
@@ -16,12 +18,12 @@ import '../utils/localized_exception_extension.dart';
 class PublicRoomBottomSheet extends StatelessWidget {
   final String roomAlias;
   final BuildContext outerContext;
-  final PublicRoomsChunk chunk;
+  final PublicRoomsChunk? chunk;
   const PublicRoomBottomSheet({
-    @required this.roomAlias,
-    @required this.outerContext,
+    required this.roomAlias,
+    required this.outerContext,
     this.chunk,
-    Key key,
+    Key? key,
   }) : super(key: key);
 
   void _joinRoom(BuildContext context) async {
@@ -31,11 +33,11 @@ class PublicRoomBottomSheet extends StatelessWidget {
       future: () => client.joinRoom(roomAlias),
     );
     if (result.error == null) {
-      if (client.getRoomById(result.result) == null) {
+      if (client.getRoomById(result.result!) == null) {
         await client.onSync.stream.firstWhere(
             (sync) => sync.rooms?.join?.containsKey(result.result) ?? false);
       }
-      VRouter.of(context).toSegments(['rooms', result.result]);
+      VRouter.of(context).toSegments(['rooms', result.result!]);
       Navigator.of(context, rootNavigator: false).pop();
       return;
     }
@@ -46,6 +48,7 @@ class PublicRoomBottomSheet extends StatelessWidget {
       (r.aliases?.contains(roomAlias) ?? false);
 
   Future<PublicRoomsChunk> _search(BuildContext context) async {
+    final chunk = this.chunk;
     if (chunk != null) return chunk;
     final query = await Matrix.of(context).client.queryPublicRooms(
           server: roomAlias.domain,
@@ -53,16 +56,15 @@ class PublicRoomBottomSheet extends StatelessWidget {
             genericSearchTerm: roomAlias,
           ),
         );
-    if (!query.chunk.any(_testRoom) ?? true) {
-      throw (L10n.of(context).noRoomsFound);
+    if (!query.chunk.any(_testRoom)) {
+      throw (L10n.of(context)!.noRoomsFound);
     }
     return query.chunk.firstWhere(_testRoom);
   }
 
   @override
   Widget build(BuildContext context) {
-    final roomAlias =
-        this.roomAlias ?? chunk.canonicalAlias ?? chunk.aliases?.first ?? '';
+    final roomAlias = this.roomAlias;
     return Center(
       child: SizedBox(
         width: min(
@@ -84,12 +86,12 @@ class PublicRoomBottomSheet extends StatelessWidget {
                 leading: IconButton(
                   icon: const Icon(Icons.arrow_downward_outlined),
                   onPressed: Navigator.of(context, rootNavigator: false).pop,
-                  tooltip: L10n.of(context).close,
+                  tooltip: L10n.of(context)!.close,
                 ),
                 actions: [
                   TextButton.icon(
                     onPressed: () => _joinRoom(context),
-                    label: Text(L10n.of(context).joinRoom),
+                    label: Text(L10n.of(context)!.joinRoom),
                     icon: const Icon(Icons.login_outlined),
                   ),
                 ],
@@ -108,26 +110,27 @@ class PublicRoomBottomSheet extends StatelessWidget {
                             color: Theme.of(context).secondaryHeaderColor,
                             child: snapshot.hasError
                                 ? Text(
-                                    snapshot.error.toLocalizedString(context))
+                                    snapshot.error!.toLocalizedString(context))
                                 : const CircularProgressIndicator.adaptive(
                                     strokeWidth: 2),
                           )
                         else
                           ContentBanner(
-                            profile.avatarUrl,
+                            profile.avatarUrl!,
                             height: 156,
                             defaultIcon: Icons.person_outline,
                             client: Matrix.of(context).client,
                           ),
                         ListTile(
-                          title: Text(profile?.name ?? roomAlias.localpart),
+                          title:
+                              Text(profile?.name ?? roomAlias.localpart ?? ''),
                           subtitle: Text(
-                              '${L10n.of(context).participant}: ${profile?.numJoinedMembers ?? 0}'),
+                              '${L10n.of(context)!.participant}: ${profile?.numJoinedMembers ?? 0}'),
                           trailing: const Icon(Icons.account_box_outlined),
                         ),
-                        if (profile?.topic != null && profile.topic.isNotEmpty)
+                        if (profile?.topic?.isNotEmpty ?? false)
                           ListTile(
-                            subtitle: Html(data: profile.topic),
+                            subtitle: Html(data: profile!.topic!),
                           ),
                       ],
                     );

lib/widgets/sentry_switch_list_tile.dart

@@ -1,13 +1,14 @@
-import 'package:flutter/material.dart';
+//@dart=2.12
 
-import 'package:flutter_gen/gen_l10n/l10n.dart';
+import 'package:flutter/material.dart';
 
 import 'package:fluffychat/utils/sentry_controller.dart';
 
 class SentrySwitchListTile extends StatefulWidget {
   final String label;
 
-  const SentrySwitchListTile.adaptive({Key key, this.label}) : super(key: key);
+  const SentrySwitchListTile.adaptive({Key? key, required this.label})
+      : super(key: key);
 
   @override
   _SentrySwitchListTileState createState() => _SentrySwitchListTileState();
@@ -23,11 +24,11 @@ class _SentrySwitchListTileState extends State<SentrySwitchListTile> {
         builder: (context, snapshot) {
           _enabled = snapshot.data ?? false;
           return SwitchListTile.adaptive(
-            title: Text(widget.label ?? L10n.of(context).sendBugReports),
+            title: Text(widget.label),
             value: _enabled,
             onChanged: (b) =>
                 SentryController.toggleSentryAction(context, b).then(
-              (_) => setState(() => null),
+              (_) => setState(() {}),
             ),
           );
         });

lib/widgets/unread_badge_back_button.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'package:flutter/material.dart';
 
 import 'package:matrix/matrix.dart';
@@ -9,8 +11,8 @@ class UnreadBadgeBackButton extends StatelessWidget {
   final String roomId;
 
   const UnreadBadgeBackButton({
-    Key key,
-    @required this.roomId,
+    Key? key,
+    required this.roomId,
   }) : super(key: key);
 
   @override