How can I populate a UIViewController after it's loaded?
<p>I'd like my UIViewController to appear on the screen with a "Loading..." UILabel in the center and then, once that's been displayed, start loading data to display.</p>

<p>How can I achieve this?  I tried loading it in viewDidAppear:, but at this point the view has still not been displayed on the screen, so the app appears unresponsive to users.  If I try setting a short timer (0.0001 seconds) so that the view will be displayed and then the data loading method gets called in the run loop after that, for some reason the time it takes from opening the view controller to seeing content is about three times as long as it was without the timer.  In this case, the Loading... text appears, but the user has to wait way too long.</p>

<p>What's the best way to do this?</p>
