title: TextBlock Binding?
body: <p>I add code in .cs</p>
  
  <pre><code> public static readonly DependencyProperty lbStatusProperty =
          DependencyProperty.Register("lbStatus", typeof(string), typeof(SingleTalkView),
          new PropertyMetadata(""));
  
      public string lbStatus
      {
          get { return (string)GetValue(lbStatusProperty); }
          set { SetValue(lbStatusProperty, value); }
      }
  </code></pre>
  
  <p>in xaml</p>
  
  <pre><code>&lt;TextBlock Text="{Binding lbStatus}" Style="{StaticResource PhoneTextNormalStyle}" Height="24"/&gt;
  </code></pre>
  
  <p>And then add a global value</p>
  
  <pre><code>private string a = "Test";
  </code></pre>
  
  <p>and in init function</p>
  
  <pre><code>this.lbStatus = a;
  </code></pre>
  
  <p>Finally I add a button and change a's value,the TextBlock doesn't change!why?
  Thx~~~~</p>