Question

The documentation says “This method is called after the view controller has loaded its associated views into memory.” My questions are:

1) if I initialize a view controller is viewDidLoad called, or does the view actually have to be added as a superview of the current view for it to be called

2) If I add the view controllers view, and viewDidLoad is called, then I remove the view controllers view, then re-add it again later, will viewDidLoad be called again?

Answer 1

viewDidLoad is called whenever the view is loaded. This happens when the vc.view property is accessed. It typically happens right before adding the view to a view hierarchy, but it can happen earlier if the property is accessed earlier.

If you remove your view from a view hierarchy, and then a memory warning happens and viewDidUnload is called, then viewDidLoad will be called again if the view property is accessed again. But this is the only way for it to be called a second time; if your view never unloads, then viewDidLoad will never be repeated.