docs: additional localization examples

packages/stream_chat_localizations/example/README.md

@@ -1,2 +1,27 @@
 # Stream Chat Persistence Example
-Please see `lib/` for example code. 
+Please see `lib/` for example code.
+
+## Setting a language
+The application language can be changed through system preferences or programmatically.
+
+### System Preferences
+The application locale can be changed by changing the language for your device or emulator within the device's system preferences.
+
+[iOS change language](https://support.apple.com/en-us/HT204031)
+
+[Android change language](https://support.google.com/websearch/answer/3333234?co=GENIE.Platform%3DAndroid&hl=en)
+
+Note that the language needs to be supported in your application to work.
+
+### Programmatically
+You can also set the locale programmatically in your Flutter application without changing the device's language.
+
+```dart
+return MaterialApp(
+ ...
+ locale: const Locale('fr'),
+ ...
+);
+```
+
+There are many ways that this can be set for additional control. For information and examples, see this [Stack Overflow post](https://stackoverflow.com/questions/49441212/flutter-multi-lingual-application-how-to-override-the-locale).

packages/stream_chat_localizations/example/lib/main.dart

@@ -76,6 +76,8 @@ class MyApp extends StatelessWidget {
         ],
         // Add GlobalStreamChatLocalizations.delegates
         localizationsDelegates: GlobalStreamChatLocalizations.delegates,
+        // Programatically set the locale (this is a global change)
+        locale: const Locale('fr'),
         builder: (context, widget) => StreamChat(
           client: client,
           child: widget,