viewDidAppear and viewWillDisappear not being called in UIViewController

Question

I am creating a UIViewController using the nib file ?

I have implemented the following 2 methods

• (void)viewDidAppear:(BOOL)animated
• (void)viewWillAppear:(BOOL)animated

in my view controller, but these methods are not getting called every time ?

What is the error in the code ?

Answer 1

从笔尖初始化时，可以使用awakeFromNib方法 。

Answer 2

Depending on how you load your viewController, your

(void)viewDidAppear:(BOOL)animated
(void)viewWillAppear:(BOOL)animated

will not get called.

Here is one way I load viewcontrollers. As you see, I explicitly call viewDidAppear, viewDidDisappear, etc. myself.