refactor: Make style settings null safe

lib/pages/settings_style/settings_style.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'dart:io';
 
 import 'package:flutter/material.dart';
@@ -12,7 +14,7 @@ import '../../widgets/matrix.dart';
 import 'settings_style_view.dart';
 
 class SettingsStyle extends StatefulWidget {
-  const SettingsStyle({Key key}) : super(key: key);
+  const SettingsStyle({Key? key}) : super(key: key);
 
   @override
   SettingsStyleController createState() => SettingsStyleController();
@@ -22,18 +24,19 @@ class SettingsStyleController extends State<SettingsStyle> {
   void setWallpaperAction() async {
     final wallpaper =
         await FilePickerCross.importFromStorage(type: FileTypeCross.image);
-    if (wallpaper == null) return;
-    Matrix.of(context).wallpaper = File(wallpaper.path);
+    final path = wallpaper.path;
+    if (path == null) return;
+    Matrix.of(context).wallpaper = File(path);
     await Matrix.of(context)
         .store
         .setItem(SettingKeys.wallpaper, wallpaper.path);
-    setState(() => null);
+    setState(() {});
   }
 
   void deleteWallpaperAction() async {
     Matrix.of(context).wallpaper = null;
     await Matrix.of(context).store.deleteItem(SettingKeys.wallpaper);
-    setState(() => null);
+    setState(() {});
   }
 
   void setChatColor(Color color) async {
@@ -48,7 +51,7 @@ class SettingsStyleController extends State<SettingsStyle> {
     );
   }
 
-  AdaptiveThemeMode currentTheme;
+  AdaptiveThemeMode? currentTheme;
 
   static final List<Color> customColors = [
     AppConfig.primaryColor,
@@ -59,7 +62,8 @@ class SettingsStyleController extends State<SettingsStyle> {
     Colors.blueGrey.shade600,
   ];
 
-  void switchTheme(AdaptiveThemeMode newTheme) {
+  void switchTheme(AdaptiveThemeMode? newTheme) {
+    if (newTheme == null) return;
     switch (newTheme) {
       case AdaptiveThemeMode.light:
         AdaptiveTheme.of(context).setLight();

lib/pages/settings_style/settings_style_view.dart

@@ -1,3 +1,5 @@
+//@dart=2.12
+
 import 'package:flutter/material.dart';
 
 import 'package:adaptive_theme/adaptive_theme.dart';
@@ -11,7 +13,7 @@ import 'settings_style.dart';
 class SettingsStyleView extends StatelessWidget {
   final SettingsStyleController controller;
 
-  const SettingsStyleView(this.controller, {Key key}) : super(key: key);
+  const SettingsStyleView(this.controller, {Key? key}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
@@ -20,7 +22,7 @@ class SettingsStyleView extends StatelessWidget {
     return Scaffold(
       appBar: AppBar(
         leading: const BackButton(),
-        title: Text(L10n.of(context).changeTheme),
+        title: Text(L10n.of(context)!.changeTheme),
       ),
       body: MaxWidthBody(
         withScrolling: true,
@@ -59,25 +61,25 @@ class SettingsStyleView extends StatelessWidget {
             RadioListTile<AdaptiveThemeMode>(
               groupValue: controller.currentTheme,
               value: AdaptiveThemeMode.system,
-              title: Text(L10n.of(context).systemTheme),
+              title: Text(L10n.of(context)!.systemTheme),
               onChanged: controller.switchTheme,
             ),
             RadioListTile<AdaptiveThemeMode>(
               groupValue: controller.currentTheme,
               value: AdaptiveThemeMode.light,
-              title: Text(L10n.of(context).lightTheme),
+              title: Text(L10n.of(context)!.lightTheme),
               onChanged: controller.switchTheme,
             ),
             RadioListTile<AdaptiveThemeMode>(
               groupValue: controller.currentTheme,
               value: AdaptiveThemeMode.dark,
-              title: Text(L10n.of(context).darkTheme),
+              title: Text(L10n.of(context)!.darkTheme),
               onChanged: controller.switchTheme,
             ),
             const Divider(height: 1),
             ListTile(
               title: Text(
-                L10n.of(context).wallpaper,
+                L10n.of(context)!.wallpaper,
                 style: TextStyle(
                   color: Theme.of(context).colorScheme.secondary,
                   fontWeight: FontWeight.bold,
@@ -99,10 +101,10 @@ class SettingsStyleView extends StatelessWidget {
               ),
             Builder(builder: (context) {
               return ListTile(
-                title: Text(L10n.of(context).changeWallpaper),
+                title: Text(L10n.of(context)!.changeWallpaper),
                 trailing: Icon(
                   Icons.photo_outlined,
-                  color: Theme.of(context).textTheme.bodyText1.color,
+                  color: Theme.of(context).textTheme.bodyText1?.color,
                 ),
                 onTap: controller.setWallpaperAction,
               );
@@ -110,7 +112,7 @@ class SettingsStyleView extends StatelessWidget {
             const Divider(height: 1),
             ListTile(
               title: Text(
-                L10n.of(context).fontSize,
+                L10n.of(context)!.fontSize,
                 style: TextStyle(
                   color: Theme.of(context).colorScheme.secondary,
                   fontWeight: FontWeight.bold,

lib/pages/story/story_view.dart

@@ -71,8 +71,10 @@ class StoryView extends StatelessWidget {
             ),
           ),
         ),
-        actions: [
-          if (!controller.isOwnStory && currentEvent != null)
+        actions: currentEvent == null
+            ? null
+            : [
+                if (!controller.isOwnStory)
                   AnimatedOpacity(
                     duration: const Duration(seconds: 1),
                     opacity: controller.isHold ? 0 : 1,