I have changed my code to this:
the view:
so I basically created a loaded event on the listbox and added this code
private void list_of_images_Loaded_1(object sender, RoutedEventArgs e)
{
ListBox lst = (ListBox)sender;
lst.ItemsSource = new_Classifieds_list[0].ImageUrls;
}
which binds the itemssource of the listbox to the list of imageurls. since I cannot access the listbox from codebehind due to it being inside the panorama's itemstemplate