iOS 8.4 - iboutlet没有在以编程方式创建的视图控制器中填充

Question

在iOS 8.4中以编程方式加载UIViewController时,我一直看到IBOutlets注册为nil.这会导致任何iOS 8.4设备崩溃.完全相同的代码在iOS 9和9.0.1上顺利运行.作为参考,这是视图控制器的片段

class B8AVPermissionsViewController: B8BaseViewController {

    @IBOutlet weak var closeButton: UIButton!
    @IBOutlet weak var cameraButton: UIButton!
    @IBOutlet weak var microphoneButton: UIButton!

    var delegate: B8PermissionRequestingDelegate? = nil;

    override func viewDidLoad() {
        super.viewDidLoad()
    }

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

    override func viewDidAppear(animated: Bool) {
        super.viewDidAppear(animated);
        NSLog("cameraButton: \(cameraButton)")
    }

打印出来 cameraButton: nil

创建它的代码如下所示:

self.permissionViewController = B8AVPermissionsViewController()
self.permissionViewController!.delegate = self
dispatch_async(dispatch_get_main_queue(), {
    self.presentViewController(self.permissionViewController!, animated: true, completion: nil)
})

我究竟做错了什么？

Answer 1

问题是iOS 8中存在错误.在iOS 8中说B8AVPermissionsViewController()不会自动加载关联的笔尖.你需要解决这个问题; 例如,您可以init(nibName:bundle:)显式调用并告诉它在nib所在的位置.

这个错误在iOS 9中得到修复,这就是为什么你没有看到同样的问题.