ios - swift deinit 方法不调用

Question

在UIViewController deinit方法中未在ios swift4.2中调用

我已尝试使用以下代码在 popToViewcontroller 导航后导航到下一个 viewController 未调用 deinit 方法。

 let data = isSearchEnabled ? repository.filteredList[index] : repository.list[index]
    let appDelegate = UIApplication.shared.delegate as! AppDelegate
    (appDelegate.window?.rootViewController as! UITabBarController).tabBar.isHidden = true
    let storyboard = UIStoryboard(name: "Main", bundle: nil)
    let viewController = storyboard.instantiateViewController(withIdentifier: "AuctionDetailsViewController") as! AuctionDetailsViewController
    viewController.auction = data.getAuctionData()
    viewController.parentVC = self
    parentNavigationController?.pushViewController(viewController, animated: true)

推送 View :

deinit {
    print("AuctionDetailsViewController deallocated...")
}

上面的deinit方法应该在popToViewcontroller上调用

Answer 1

您需要了解 iOS 使用 ARC 进行的内存管理。您可以阅读此here

Deinit() 不会被调用，如果 viewcontoller...

holds the strong reference of an object(retain cycle)

you need to check and remove the unnecessary strong references to an object to avoid retail cycle

有通知观察者

you need to unregister an observer because the notification center retains the observer until you unregister it.

委托(delegate)的使用(持有它的强引用)

if view controller is confirming the protocol that delegate should be marked as weak.

上面提到的是阻止 View Controller dealloc和deinit永远不会被调用的一些要点。可能还有其他原因。