Made Settings persistent with autosave

lib/theming/appTheme.dart

@@ -0,0 +1,28 @@
+import 'package:flutter/material.dart';
+
+class AppTheme {
+  static ThemeModeDisplay getDisplayOptions(ThemeMode theme) {
+    switch(theme) {
+      case ThemeMode.system:
+        return ThemeModeDisplay(icon: Icons.auto_fix_high_outlined, displayName: "Systemvorgabe");
+
+      case ThemeMode.light:
+        return ThemeModeDisplay(icon: Icons.dark_mode_outlined, displayName: "Hell");
+
+      case ThemeMode.dark:
+        return ThemeModeDisplay(icon: Icons.dark_mode, displayName: "Dunkel");
+
+    }
+  }
+
+  static bool isDarkMode(BuildContext context) {
+    return Theme.of(context).brightness == Brightness.dark;
+  }
+}
+
+class ThemeModeDisplay {
+  final IconData icon;
+  final String displayName;
+
+  ThemeModeDisplay({required this.icon, required this.displayName});
+}