Question

我创建了一个自定义的TabBarController并添加了一些带有图像的按钮。但我发现每次加载TabBarController而不做任何事情并立即解除它时，内存会永久增加。我在代码中找不到任何问题。请帮忙。提前谢谢！

    class CustomTabBarController: UITabBarController {

    var menuButton: UIButton!
    var announcementButton : UIButton!
    var broadcastButton: UIButton!
    var toDoListButton: UIButton!
    var plusMenuBool = false

    override func viewDidLoad() {
        super.viewDidLoad()

        let newInfo = UIImage(named: "info")!.imageResize(sizeChange: CGSize(width: 30, height: 30))
        self.viewControllers![0].tabBarItem.image = newInfo

        let newChat = UIImage(named: "chat")!.imageResize(sizeChange: CGSize(width: 30, height: 30))
        self.viewControllers![1].tabBarItem.image = newChat

        self.setupMiddleButton()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func setupMiddleButton() {
        // menuButton
        menuButton = UIButton(frame: CGRect(x: 0, y: 0, width: 64, height: 64))
        var menuButtonFrame = menuButton.frame
        menuButtonFrame.origin.y = self.view.bounds.height - menuButtonFrame.height
        menuButtonFrame.origin.x = self.view.bounds.width/2 - menuButtonFrame.size.width/2
        menuButton.frame = menuButtonFrame

        // announcementButton
        announcementButton = UIButton(frame: CGRect(x: 0, y: 0, width: 44, height: 44))
        var announcementButtonFrame = announcementButton.frame
        announcementButtonFrame.origin.y = self.view.bounds.height - announcementButtonFrame.height
        announcementButtonFrame.origin.x = self.view.bounds.width/2 - announcementButtonFrame.size.width/2
        announcementButton.frame = announcementButtonFrame

        self.announcementButton.layer.anchorPoint = CGPoint(x: 0.5, y: 3.5)
        announcementButton.transform = CGAffineTransform(rotationAngle: CGFloat(M_PI*3/4))

        // broadcastButton
        broadcastButton = UIButton(frame: CGRect(x: 0, y: 0, width: 44, height: 44))
        var broadcastButtonFrame = broadcastButton.frame
        broadcastButtonFrame.origin.y = self.view.bounds.height - broadcastButtonFrame.height
        broadcastButtonFrame.origin.x = self.view.bounds.width/2 - broadcastButtonFrame.size.width/2
        broadcastButton.frame = broadcastButtonFrame

        self.broadcastButton.layer.anchorPoint = CGPoint(x: 0.5, y: 3.5)
        broadcastButton.transform = CGAffineTransform(rotationAngle: CGFloat(M_PI))

        // toDoListButton
        toDoListButton = UIButton(frame: CGRect(x: 0, y: 0, width: 44, height: 44))
        var toDoListButtonFrame = toDoListButton.frame
        toDoListButtonFrame.origin.y = self.view.bounds.height - toDoListButtonFrame.height
        toDoListButtonFrame.origin.x = self.view.bounds.width/2 - toDoListButtonFrame.size.width/2
        toDoListButton.frame = toDoListButtonFrame

        self.toDoListButton.layer.anchorPoint = CGPoint(x: 0.5, y: 3.5)
        toDoListButton.transform = CGAffineTransform(rotationAngle: CGFloat(M_PI+M_PI/4))

        // addSubView
        menuButton.layer.cornerRadius = menuButtonFrame.height/2
        announcementButton.layer.cornerRadius = announcementButtonFrame.height/2
        broadcastButton.layer.cornerRadius = announcementButtonFrame.height/2
        toDoListButton.layer.cornerRadius = announcementButtonFrame.height/2
        self.view.addSubview(menuButton)
        self.view.addSubview(announcementButton)
        self.view.addSubview(broadcastButton)
        self.view.addSubview(toDoListButton)

        menuButton.setImage(UIImage(named: "plus"), for: UIControlState.normal)
        menuButton.addTarget(self, action: #selector(self.menuButtonAction(sender:)), for: UIControlEvents.touchUpInside)
        announcementButton.setImage(UIImage(named: "announcement"), for: .normal)
        announcementButton.addTarget(self, action: #selector(self.announcementButtonAction(sender:)), for: UIControlEvents.touchUpInside)
        broadcastButton.setImage(UIImage(named: "broadcast"), for: .normal)
        broadcastButton.addTarget(self, action: #selector(self.broadcastButtonAction(sender:)), for: UIControlEvents.touchUpInside)
        toDoListButton.setImage(UIImage(named: "toDoList"), for: .normal)
        toDoListButton.addTarget(self, action: #selector(self.toDoListButtonAction(sender:)), for: UIControlEvents.touchUpInside)

        self.view.layoutIfNeeded()
    }
}

Answer 1

结帐memory management in swift。

为了确保实例在仍然需要时不会消失，ARC会跟踪当前引用每个类实例的属性，常量和变量的数量。只要至少有一个对该实例的活动引用仍然存在，ARC就不会解除分配实例。

简而言之，您可以执行以下操作之一：

检查tabBar是否已取消分配。简单地解雇并不能保证。
即使取消分配tabBar，您也不会立即看到内存减少。
检查是否有其他对象引用了tabBar。这可能导致tabBar挂起，因为ARC会认为您可能需要引用。

Swift TabBarController没有正确解除分配？

1 个答案: