Initial strings setup

lib/l10n/intl_en.arb

@@ -1,7 +1,23 @@
 {
   "@@locale": "en",
-  "addAccount": "Add account",
-  "@addAccount": {},
-  "selectInstance": "select instance",
-  "@selectInstance": {}
+  "add_account": "Add account",
+  "@add_account": {},
+  "select_instance": "select instance",
+  "@select_instance": {},
+  "accounts": "Accounts",
+  "@accounts": {},
+  "appearance": "Appearance",
+  "@appearance": {},
+  "settings": "Settings",
+  "@settings": {},
+  "add_instance": "Add instance",
+  "@add_instance": {},
+  "username_or_email": "Username or email",
+  "@username_or_email": {},
+  "password": "Password",
+  "@password": {},
+  "sign_in": "Sign in",
+  "@sign_in": {},
+  "register": "Register",
+  "@register": {}
 }

lib/l10n/intl_pl.arb

@@ -1,5 +1,5 @@
 {
   "@@locale": "pl",
-  "addAccount": "Dodaj konto",
-  "selectInstance": "Wybierz instancje"
+  "add_account": "Dodaj konto",
+  "select_instance": "Wybierz instancje"
 }

lib/l10n/l10n.dart

@@ -1 +1,15 @@
+import 'package:flutter/material.dart';
+
 export 'package:flutter_gen/gen_l10n/l10n.dart';
+
+abstract class LocaleSerde {
+  static Locale fromJson(String json) {
+    if (json == null) return null;
+
+    final lang = json.split('-');
+
+    return Locale(lang[0], lang.length > 1 ? lang[1] : null);
+  }
+
+  static String toJson(Locale locale) => locale.toLanguageTag();
+}

lib/l10n/untranslated.json

@@ -1,5 +1,12 @@
 {
   "pl": [
-    "selectInstance"
+    "accounts",
+    "appearance",
+    "settings",
+    "add_instance",
+    "username_or_email",
+    "password",
+    "sign_in",
+    "register"
   ]
 }

lib/pages/add_account.dart

@@ -7,6 +7,7 @@ import 'package:url_launcher/url_launcher.dart' as ul;
 
 import '../hooks/delayed_loading.dart';
 import '../hooks/stores.dart';
+import '../l10n/l10n.dart';
 import '../widgets/fullscreenable_image.dart';
 import '../widgets/radio_picker.dart';
 import 'add_instance.dart';
@@ -58,7 +59,7 @@ class AddAccountPage extends HookWidget {
       key: scaffoldKey,
       appBar: AppBar(
         leading: const CloseButton(),
-        title: const Text('Add account'),
+        title: Text(L10n.of(context).add_account),
       ),
       body: ListView(
         padding: const EdgeInsets.all(15),
@@ -77,7 +78,7 @@ class AddAccountPage extends HookWidget {
               ),
             ),
           RadioPicker<String>(
-            title: 'select instance',
+            title: L10n.of(context).select_instance,
             values: accountsStore.instances.toList(),
             groupValue: selectedInstance.value,
             onChanged: (value) => selectedInstance.value = value,
@@ -96,7 +97,7 @@ class AddAccountPage extends HookWidget {
                 padding: EdgeInsets.all(8),
                 child: Icon(Icons.add),
               ),
-              title: const Text('Add instance'),
+              title: Text(L10n.of(context).add_instance),
               onTap: () async {
                 final value = await showCupertinoModalPopup<String>(
                   context: context,
@@ -110,13 +111,14 @@ class AddAccountPage extends HookWidget {
           TextField(
             autofocus: true,
             controller: usernameController,
-            decoration: const InputDecoration(labelText: 'Username or email'),
+            decoration:
+                InputDecoration(labelText: L10n.of(context).username_or_email),
           ),
           const SizedBox(height: 5),
           TextField(
             controller: passwordController,
             obscureText: true,
-            decoration: const InputDecoration(labelText: 'Password'),
+            decoration: InputDecoration(labelText: L10n.of(context).password),
           ),
           ElevatedButton(
             onPressed: usernameController.text.isEmpty ||
@@ -126,7 +128,7 @@ class AddAccountPage extends HookWidget {
                     ? () {}
                     : handleOnAdd,
             child: !loading.loading
-                ? const Text('Sign in')
+                ? Text(L10n.of(context).sign_in)
                 : SizedBox(
                     width: 20,
                     height: 20,
@@ -138,9 +140,10 @@ class AddAccountPage extends HookWidget {
           ),
           TextButton(
             onPressed: () {
+              // TODO: extract to LemmyUrls or something
               ul.launch('https://${selectedInstance.value}/login');
             },
-            child: const Text('Register'),
+            child: Text(L10n.of(context).register),
           ),
         ],
       ),

lib/pages/settings.dart

@@ -6,6 +6,7 @@ import 'package:flutter_slidable/flutter_slidable.dart';
 import 'package:flutter_speed_dial/flutter_speed_dial.dart';
 
 import '../hooks/stores.dart';
+import '../l10n/l10n.dart';
 import '../util/goto.dart';
 import '../widgets/about_tile.dart';
 import 'add_account.dart';
@@ -68,11 +69,24 @@ class AppearanceConfigPage extends HookWidget {
               },
             ),
           SwitchListTile(
-              title: const Text('AMOLED dark mode'),
-              value: configStore.amoledDarkMode,
-              onChanged: (checked) {
-                configStore.amoledDarkMode = checked;
-              })
+            title: const Text('AMOLED dark mode'),
+            value: configStore.amoledDarkMode,
+            onChanged: (checked) {
+              configStore.amoledDarkMode = checked;
+            },
+          ),
+          const SizedBox(height: 12),
+          const _SectionHeading('Language'),
+          for (final locale in L10n.supportedLocales)
+            RadioListTile<Locale>(
+              value: locale,
+              // TODO: add actual language names
+              title: Text(locale.languageCode),
+              groupValue: configStore.locale,
+              onChanged: (selected) {
+                configStore.locale = selected;
+              },
+            ),
         ],
       ),
     );

lib/stores/config_store.dart

@@ -5,6 +5,8 @@ import 'package:flutter/material.dart';
 import 'package:json_annotation/json_annotation.dart';
 import 'package:shared_preferences/shared_preferences.dart';
 
+import '../l10n/l10n.dart';
+
 part 'config_store.g.dart';
 
 /// Store managing user-level configuration such as theme or language
@@ -32,7 +34,9 @@ class ConfigStore extends ChangeNotifier {
   }
 
   Locale _locale;
-  @JsonKey(defaultValue: Locale('en'))
+  // default value is set in the `load` method because json_serializable does
+  // not accept non-literals as constant values
+  @JsonKey(fromJson: LocaleSerde.fromJson, toJson: LocaleSerde.toJson)
   Locale get locale => _locale;
   set locale(Locale locale) {
     _locale = locale;
@@ -45,7 +49,7 @@ class ConfigStore extends ChangeNotifier {
 
     return _$ConfigStoreFromJson(
       jsonDecode(prefs.getString(prefsKey) ?? '{}') as Map<String, dynamic>,
-    );
+    ).._locale ??= const Locale('en');
   }
 
   Future<void> save() async {

lib/stores/config_store.g.dart

@@ -10,13 +10,15 @@ ConfigStore _$ConfigStoreFromJson(Map<String, dynamic> json) {
   return ConfigStore()
     ..theme = _$enumDecodeNullable(_$ThemeModeEnumMap, json['theme']) ??
         ThemeMode.system
-    ..amoledDarkMode = json['amoledDarkMode'] as bool ?? false;
+    ..amoledDarkMode = json['amoledDarkMode'] as bool ?? false
+    ..locale = LocaleSerde.fromJson(json['locale'] as String);
 }
 
 Map<String, dynamic> _$ConfigStoreToJson(ConfigStore instance) =>
     <String, dynamic>{
       'theme': _$ThemeModeEnumMap[instance.theme],
       'amoledDarkMode': instance.amoledDarkMode,
+      'locale': LocaleSerde.toJson(instance.locale),
     };
 
 T _$enumDecode<T>(