ios – 实例化ViewController w / xib时的帧大小不正确

我有一个视图控制器,看起来像：

class SpotViewController: UIViewController {
  let spot: Spot

  init(spot: Spot) {
    self.spot = spot
    super.init(nibName: "SpotViewController",bundle: nil)
  }

  override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)

    print("viewWillAppear: \(view.frame)") # => (0.0,0.0,600.0,600.0)
  }

  override func viewDidLoad() {
    super.viewDidLoad()

    print("viewDidLoad: \(view.frame)") # => (0.0,600.0)
  }
}

当我通过让spotViewController = SpotViewController(spot：spot)实例化视图控制器并将其推送到导航控制器时,结果框架在viewDidLoad和viewWillAppear中都是不正确的.它给了我(0.0,600.0)这是界面构建器中的大小.

为什么会发生这种情况以及使用xib实例化视图控制器以确保帧正确的正确方法是什么？

解决方法

这将解决您的问题,UIViewController从xib加载,在viewDidLoad期间保持xib大小：

extension UIViewController {
    public override class func initialize() {
        struct Static {
            static var token: dispatch_once_t = 0
        }
        if self !== UIViewController.self {
            return
        }
        dispatch_once(&Static.token) {
            pb_applyFixToViewFrameWhenLoadingFromNib()
        }
    }

    @objc func pb_setView(view: UIView!) {
        // View is loaded from xib file
        if nibBundle != nil && storyboard == nil {
            view.frame = UIScreen.mainScreen().bounds
            view.layoutIfNeeded()
        }
        pb_setView(view)
    }

    private class func pb_applyFixToViewFrameWhenLoadingFromNib() {
        UIViewController.swizzleMethodSelector(NSSelectorFromString("setView:"),withSelector: #selector(UIViewController.pb_setView(_:)))
        UICollectionView.swizzleMethodSelector(#selector(UICollectionView.layoutSubviews),withSelector: #selector(UICollectionView.pb_layoutSubviews))
        UITableView.swizzleMethodSelector(#selector(UITableView.layoutSubviews),withSelector: #selector(UITableView.pb_layoutSubviews))
    }
}

extension UITableView {
    @objc private func pb_layoutSubviews() {
        if dataSource == nil {
            super.layoutSubviews()
        } else {
            pb_layoutSubviews()
        }
    }
}

extension UICollectionView {
    @objc private func pb_layoutSubviews() {
        if dataSource == nil {
            super.layoutSubviews()
        } else {
            pb_layoutSubviews()
        }
    }
}