ios - PerformSegue 被调用但实际上并未转至 VC2？ ( swift 3.0)

Question

有人能发现我的错误吗？左栏按钮可以关闭，但是操作按钮调用 performSegue 但 UI 没有更改 VC？在 ViewDidLoad 中调用 showLinkPreviewController 可以工作，所以显然这是目标/操作的问题？一个错误？

     let button = UIBarButtonItem(barButtonSystemItem: .done, target: self, action: #selector(dismissTimeline))
            timelineViewController.navigationItem.leftBarButtonItem = button

            let previewButton = UIBarButtonItem(barButtonSystemItem: .action, target: self, action: #selector(showLinkPreviewViewController))
            timelineViewController.navigationItem.rightBarButtonItem = previewButton

            // Create a navigation controller to hold the
            let navigationController = UINavigationController(rootViewController: timelineViewController)
            showDetailViewController(navigationController, sender: self)
        }
        func dismissTimeline() {
            dismiss(animated: true, completion: nil)
        }

        func showLinkPreviewViewController() {
            self.performSegue(withIdentifier: "showLinkPreviewViewController", sender: self)
        }

  // Create a navigation controller to hold the
        let navigationController = UINavigationController(rootViewController: timelineViewController)
        showDetailViewController(navigationController, sender: self)

Answer 1

你应该像这样使用调度 -

dispatch_async(dispatch_get_main_queue(), ^{
    [self.navigationController pushViewController:[self.storyboard instantiateViewControllerWithIdentifier:@"thirdScreen"] animated:YES];
});

或者其他方式 -

dispatch_async(dispatch_get_main_queue(), ^{
   func showLinkPreviewViewController() {
            self.performSegue(withIdentifier: "showLinkPreviewViewController", sender: self)
        }

});