故事板popover被解雇，委托方法未被调用

Question

我有一个使用故事板segue在弹出框中显示的视图控制器。

在呈现视图控制器中，我有以下代码：

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if let svc = segue.destinationViewController as? SettingsViewController {
        svc.popoverPresentationController?.delegate = self
    }
}

然而，事实证明，呈现的视图控制器即使显示为弹出框，也有modalPresentationStyle '.Modal，因此nil popoverPresentationController。奇怪的！

所以，我更新了代码如下：

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
    if let svc = segue.destinationViewController as? SettingsViewController {
        svc.modalPresentationStyle = .Popover
        svc.popoverPresentationController?.delegate = self
    }
}

svc.popoverPresentationController委托现在设置为OK，但如果用户点击外部时弹出窗口被忽略，则UIPopoverPresentationControllerDelegate委托方法（例如popoverPresentationControllerShouldDismissPopover）都不会被调用。我是什么人丢失？

Answer 1

在这种情况下无需代表团。如果presentingViewController（任何vc包含popover）只是覆盖：

Swift 4

override func dismiss(animated flag: Bool, completion: (() -> Void)? = nil) {
    print("Dismiss: \(String(describing: self.presentedViewController))")
    super.dismiss(animated: flag, completion: completion)
}

Swift 3

override func dismissViewControllerAnimated(flag: Bool, completion: (() -> Void)?) {
    // Before calling super get a handle on which controller is being dismissed
    print("Dismiss: \(self.presentedViewController)")
    super.dismissViewControllerAnimated(flag, completion: completion)
}

无论如何解雇，您都会收到通知。您也无需在prepareForSegue:中设置任何其他变量/设置（至少可以处理此交互）。

Answer 2

遇到同样的问题，在阅读完文档后，我意识到你需要打电话：

[self presentViewController:myPopoverViewController animated: YES completion: nil];

以便调用委托方法。

完整代码段如下所示，并在我的 - （void）prepareForSegue：sender方法中运行：

// Present the view controller using the popover style.
myPopoverViewController.modalPresentationStyle = UIModalPresentationPopover;
[self presentViewController:myPopoverViewController animated: YES completion: nil];

// Get the popover presentation controller and configure it.
UIPopoverPresentationController *presentationController =
         [myPopoverViewController popoverPresentationController];
presentationController.permittedArrowDirections =
         UIPopoverArrowDirectionLeft | UIPopoverArrowDirectionRight;
presentationController.sourceView = myView;
presentationController.sourceRect = sourceRect;

https://developer.apple.com/documentation/uikit/uipopoverpresentationcontroller