content localized on locale change

lib/providers/locale_provider.dart

@@ -0,0 +1,12 @@
+import 'package:flutter/material.dart';
+
+class LocaleProvider extends ChangeNotifier {
+  Locale _locale = const Locale('de');
+
+  Locale get locale => _locale;
+
+  void setLocale(Locale locale) {
+    _locale = locale;
+    notifyListeners();
+  }
+}