ios - ViewController deinit 后 UIImageView 内存泄漏

Question

我有一个 ViewController，带有填充整个 vc 的 imageView 的 subview ，当我呈现新的 VC 并关闭旧的 VC 时，调用了 oldVC 的 deinit 但内存仍然存在，仪器显示我与 imageio 相关，主要问题是为什么调用 oldvc 的 deinit 但图像在内存中保留..这是我的 oldvc 代码:

class Vc1: UIViewController {

@IBOutlet weak var vcimage: UIImageView!
override func viewDidLoad() {
    super.viewDidLoad()
    vcimage.image = UIImage.init(named: "splash")
    // Do any additional setup after loading the view.
}
@IBAction func tovc2(_ sender: Any) {
    let vc = self.storyboard?.instantiateViewController(withIdentifier: "vc2")
    AnimateTovc(ViewControllerToAnimate: vc!, vctoDissmiss: self)
}
override func didReceiveMemoryWarning() {
    print("memory warning")
}
func AnimateTovc(duration:Float = 0.5,Animateoption:UIViewAnimationOptions = .transitionFlipFromLeft,ViewControllerToAnimate vc:UIViewController,vctoDissmiss: UIViewController?,completion : @escaping ()->Void = {} ){
    let appDelegate = UIApplication.shared.delegate as! AppDelegate
    UIView.transition(with: appDelegate.window!, duration: TimeInterval(duration), options: Animateoption , animations: { () -> Void in
        appDelegate.window!.rootViewController = vc
    }, completion:{ isfinished in
        completion()
        vctoDissmiss?.dismiss(animated: false, completion: nil)
    })
}
deinit {
    print("removed \(self) from memory")
}
}

奇怪的是，当应用程序进入后台时，内存在 newvc 中被释放，而 imageio 部分从内存中释放。

Answer 1

感谢 Allen，使用 UIImage(contentsOfFile:) 解决了这个问题。

根据 Apple 文档:

Use the init(named:in:compatibleWith:) method (or the init(named:) method) to create an image from an image asset or image file located in your app’s main bundle (or some other known bundle). Because these methods cache the image data automatically, they are especially recommended for images that you use frequently.

Use the imageWithContentsOfFile: or init(contentsOfFile:) method to create an image object where the initial data is not in a bundle. These methods load the image data from disk each time, so you should not use them to load the same image repeatedly.