如何在UWP中以编程方式更改ContentTemplateRoot？

Question

I would like to change the ListBoxItem's ContentTemplateRoot property programmatically. It contains a textblock, but I want to group it into a grid and add a few new elements.

I have my own class:

public class MyListboxItemClass : ListBoxItem
{  
      protected override void OnPointerMoved(PointerRoutedEventArgs e)       
      {           
       // here I want to add those new elements as parent of my content...        
      }
}

I tried to simply change the Content, but it doesn't work...

Actually I want to change the ContentTemplateRoot property to a Grid...

Answer 1

I have made this, it looks like it works: (it's only to show how can do it, not perfect, has some unnecessary code)

 private object oldRootContent;

public ListboxGestureHandlerItem()
{
    Loaded += ListboxGestureHandlerItem_Loaded;
    LayoutUpdated += ListboxGestureHandlerItem_LayoutUpdated;
}

private void ListboxGestureHandlerItem_LayoutUpdated(object sender, object e)
{
    if(oldRootContent != null && (ContentTemplateRoot as Grid) != null)
    {
        (ContentTemplateRoot as Grid).Children.Add(oldRootContent as FrameworkElement);
        oldRootContent = null;
    }
}

private void ListboxGestureHandlerItem_Loaded(object sender, Windows.UI.Xaml.RoutedEventArgs e)
{
    oldRootContent = (sender as ListboxGestureHandlerItem).ContentTemplateRoot;

    this.ContentTemplate = Create(typeof(Grid));
}

protected override void OnPointerMoved(PointerRoutedEventArgs e)
{
    base.OnPointerMoved(e);
}

public DataTemplate Create(Type type)
{
    return XamlReader.Load(@"<DataTemplate 
xmlns=""http://schemas.microsoft.com/winfx/2006/xaml/presentation""> 
    <" + type.Name + @"/> 
</DataTemplate>") as DataTemplate;
}