Data binding 将灯光开关属性加载到Silverlight控件

但当我运行此程序时，对象结果为null，因为在加载lightswitch屏幕之前调用了预定义的Loaded silverlight函数，当我调用按钮上的方法get属性时，单击结果不是null，因为加载了lightswitch屏幕。所以，我的问题是，在屏幕以某种昂贵的方式加载后，如何调用此方法，无需单击按钮。

好的，我这样解决了它

 I have control like this

<UserControl x:Class="VideoControl.VideoControl" Loaded="getProperty"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
</UserControl>

private void getProperty(object sender, RoutedEventArgs e) {
  var objContext = (IContentItem)this.DataContext;
  var Scrn = (Microsoft.LightSwitch.Client.IScreenObject)objContext.Screen;
  var anonObject = Scrn.Details.Properties["VidContentItemRessourcesItem"].Value;

    string result= anonObject.GetType().GetProperty("AssetPubLocator").GetValue(anonObject, null).ToString();

}

 // My control property
public MyControlType MyControl;

    partial void MyEntity_Loaded(bool succeeded) {

      this.SetDisplayNameFromEntity(this.MyEntity);
      // Open in new Thread
      Microsoft.LightSwitch.Threading.Dispatchers.Main.BeginInvoke(() => {
        this.FindControl("VideoControler").ControlAvailable += (s, e) => {
          // Loading Control
          MyControl = (e.Control as MyControlNamespace.MyControlType);
        };

        // Calling method in Control and sending property there :-)
        MyControl.PropertiesLoaded(this.MyEntity.SomeString);
      });
    }