private void SayName_Button_Click(object sender, RoutedEventArgs e)
        {
            // Define a new List of dogs
            List <Dog> dogs = new List <Dog>();

            // Instantiate some dog objects
            Dog dog1 = new Dog("Muppet", 20, "Rolf");
            Dog dog2 = new Dog("Golden Retriever", 30, "Air Bud");

            // Add the dogs to the list
            dogs.Add(dog1);
            dogs.Add(dog2);

            // Loop through the list and call a method on the objects
            foreach (Dog d in dogs)
            {
                d.SayName();
            }

            // Ducks and Frogs
            Duck duck1 = new Duck(9, "Donald");

            duck1.SayName();

            Frog frog1 = new Frog(4, "Kermit", false);

            frog1.SayName();
        }
        public MainWindow()
        {
            InitializeComponent();
            Animals = new ObservableCollection <Animal>();

            Dog  dog1  = new Dog("Muppet", 20, "Rolf");
            Dog  dog2  = new Dog("Golden Retriever", 30, "Air Bud");
            Duck duck1 = new Duck(9, "Donald");

            Frog frog1 = new Frog(4, "Kermit", false);

            duck1.SayName();
            frog1.SayName();

            Animals.Add(dog1);
            Animals.Add(dog2);
            Animals.Add(duck1);
            Animals.Add(frog1);

            LvAnimals.ItemsSource = Animals;
        }