在关闭当前ViewController之后快速显示，然后Presenting ViewController不调用viewWillAppear（）

Question

In my case, I am using two view controller VC1 and VC2 . Here, VC1 button click to Present Modally and Over Full Screen presentation with Cross Dissolve Transition to presenting VC2. Now, from VC2 dismiss then I didn't get call VC1 viewWillAppear() .

I am not using code base for Present model. I am using Storyboard Segue .

Why it happening and how to fix this?

Answer 1

From Docs ,

Note

If a view controller is presented by a view controller inside of a popover, this method is not invoked on the presenting view controller after the presented controller is dismissed.

So according to the documentation when a ViewController presents another ViewController modally this method will not be called. To fix this you need to use

func dismiss(animated flag: Bool, 
  completion: (() -> Void)? = nil)

and move(or repeat) some of viewWillLoad logic to completion handler.

Answer 2

Change presentation to Full screen or If you want to stick to Over Full Screen then make vc2 delegate of vc1 and call delegate method on dismiss.

To understand the concept you can refer to : https://medium.com/livefront/why-isnt-viewwillappear-getting-called-d02417b00396