iOS dismissing a view controller doesn't release memory

Question

I know it's all with the weak strong reference when presenting the viewController in the parent view ... correct me please if I'm wrong

this is an example how I do it

let viewHolder = viewClass()

func presentView()  {
    self.present(viewHolder, animated: true) {

    }
}

see my memory monitor only from open and dismiss the same view over and over

I have tried this

weak var viewHolder = viewClass()

func presentView()  {
    self.present(viewHolder!, animated: true) {

    }
}

but this would give me a crash

Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value

and dismiss the viewClass this way (inside itself off)

func dismissPage()  {
    self.dismiss(animated: true)
}

any help would be appreciated thanks

Answer 1

1. Use deint method and check weather it is called or not after dismiss your viewcontroller.

2. if your using any kind of blocks or closure to work done then use [weak self] in side your closure.

3. your can also make nil your property/delegate/variable when viewDidDisappeared only if after there is no view controller will be presented or pushed

Answer 2

The problem might not be in the viewClass. You are declaring let viewHolder = viewClass() in your initial class. So when you dismiss the controller, that variable still exists. Do you need to keep a reference to it? If not, you can easily allocate it when needs to be displayed and when you dismiss it, the memory is going to be freed:

func presentView()  {
     // instead of saving viewHolder as an instance variable, you declare it locally
    let viewHolder = viewClass()
    self.present(viewHolder, animated: true) {

    }
}