title: How to determine when the user control is fully loaded and shown?
body: <p>There were already a few similar questions on stackoverflow, but I haven't found the answer</p>
  
  <p>I have an application that consists of several tab pages. On one of them I'm loading a list of a few dozen user controls at a time. Currently I'm doing it in Load event and because of that I have a small delay before this page is loaded. What I want to do is to make UI more responsive and fill the list after the page is fully loaded. Is there any way to track when the user control has fully loaded it's content?</p>
  
  <p>VisibleChanged doesn't help too, because it fires before any other child control is shown. That causes some ugly visual effects when some of the child controls are still not visible when I'm starting to load control list.</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>To make it more clear. I have some child controls on a page container and I have a list of custom controls I'm trying to load later. The problem with two approaches described in several answers below is that when I'm starting to load controls they do not let other child controls on the container to be shown and that is why I have those ugly effects (and I'm doing that with BackgroundWorker, but anyway it has to interact with the main thread to add controls to the list)</p>