Low frame rate during UINavigationController push transition

Question

I have a UINavigationController, and push from the root view controller to the next view controller. This second view controller is fairly \"heavy\", in that it

Answer 1

I have not stumbled upon this with the navigation controller but I got much the same result when updating a table view from another thread, the UI was really slow to update at first but after a short delay everything was showing again. As Justin points out in a comment, you should do UI work on the main thread. A simple way to accomplish this is wrap your call to the UI in a GCD block:

dispatch_sync(dispatch_get_main_queue(), ^{
// Do UI stuff here
});

or use

performSelectorOnMainThread:withObject:waitUntilDone: