Question

我遇到了某种内存管理问题。我有一个UIViewController的子类，我手动设置了它的视图，以便引用回viewController并避免引用周期我使用weak/unowned。现在问题是，如果我使用unowned我有内存泄漏但是如果我使用weak我没有。我无法弄清楚为什么会这样？

更新：这似乎是一个错误。

控制台输出：

removing vc
view Controller deinitialized
custom view deinitialized

我正在使用xcode 8.3.1

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {

    window = UIWindow(frame: UIScreen.main.bounds)
    window?.rootViewController = ViewController(nibName: nil, bundle: nil)
    window?.makeKeyAndVisible()

    DispatchQueue.main.asyncAfter(deadline: .now() + 5) { 
        print("removing vc")
        self.window?.rootViewController = nil
    }

    return true
}


class ViewController: UIViewController {

    override func loadView() {
        view = CustomView(frame: .zero, vc: self)
        view.backgroundColor = .red
    }

    deinit {
        print("view Controller deinitialized")
    }
}

class CustomView:UIView{

    init(frame: CGRect , vc:ViewController) {
        self.vc = vc
        super.init(frame: frame)
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    //    weak var vc : ViewController!   // no leak
    unowned var vc : ViewController   // leak

    deinit {
        print("custom view deinitialized")
    }
}

Answer 1

Xcode 8.2发行说明：

macOS的内存调试器和iOS模拟器修复了报告包含任一类型字段的Swift类的错误内存泄漏枚举，或从某些Objective-C框架继承的类类。（27932061）

无主参考导致泄漏，弱无效

1 个答案: