Are you familiar with the mechanism that manages the lifecycle of UIViewController and helps prevent memory leaks?

In iOS, the lifecycle of UIViewController is managed by the system, which calls methods like viewDidLoad, viewWillAppear, viewDidAppear, viewWillDisappear, viewDidDisappear, and deinit. To prevent memory leaks, the ARC (Automatic Reference Counting) mechanism is important, which automatically manages the lifetime of objects.

To avoid strong reference cycles (retain cycles), especially when using closures inside UIViewController, weak (weak) or unowned (unowned) references are used. For example, when using a closure that captures self, you should write:

someAsyncCall { [weak self] in
    guard let self = self else { return }
    self.doSomething()
}

This prevents the controller from being retained in memory after it is closed, helping to avoid leaks.

It is also important to properly release resources in the deinit method and to ensure that delegates are declared as weak if possible.