如何在“绑定时”的列表框中获取项的列表项

I have a ListBox with Foo objects, and based on some events I disable/enable the ListBoxItems in the ListBox. Using the ListBox.Items property I find Foo objects, and from what I've understood I need to use the following function to get the ListBoxItem container for the Foo. Correct? I have a ListBox with Foo objects, and based on