Update README.md

Author: vandadnp

README.md

@@ -1,5 +1,6 @@
 # Table of Contents
 
+* [Enum Annotations in Flutter](#enum-annotations-in-flutter)
 * [Sorting Generics in Dart](#sorting-generics-in-dart)
 * [Animating FAB in Flutter](#animating-fab-in-flutter)
 * [Image Gallery in Flutter](#image-gallery-in-flutter)
@@ -323,6 +324,12 @@
 * [Extract Minimum and Maximum Values in `List<num>` in Dart](#4-lines-of-dart-code-that-include-the-spread-operator-cascade-operator-generics-extensions-private-prefix-and-getters)
 * [Functions as First Class Citizens in Dart](#functions-as-first-class-citizens-in-dart)
 
+# Enum Annotations in Flutter
+
+[Source Code](source/enum-annotations-in-flutter.dart)
+
+![](images/enum-annotations-in-flutter.jpg)
+
 # Sorting Generics in Dart
 
 [Source Code](source/sorting-generics-in-dart.dart)