title: Bind a List<string> to a combobox
body: <p>I have a list of strings.
  I wanna populate a combo box with a list of strings. how do I do this?
  All my tries and searchs are dead end.</p>
  
  <p>i used:</p>
  
  <pre><code>&lt;ComboBox  Name="comboBox2" ItemsSource="{Binding Combobox2items}" /&gt;
   public partial class EditRule : Window
  {
      public ObservableCollection&lt;string&gt; Combobox2items { get;  set; }
  
      public EditRule()
      {
          InitializeComponent();
          Combobox2items = new ObservableCollection&lt;string&gt;();
      Combobox2items.Add("DFd");
  
      }}
  </code></pre>
  
  <p>EDIT:
  adding <code>Combobox2items.ItemsSource = Combobox2items;</code> 
  works, but why ItemsSource="{Binding Combobox2items}" doesn't?</p>