解散模式vc swift之后的popviewcontroller

Question

我想在解散modalvc之后popviewController。但是我的代码不起作用。怎么了？

func showMessage(withTitle title: String, message: String) {

        let alert = UIAlertController(title: title, message: message, preferredStyle: .alert)

        let alertAction = UIAlertAction(title: "ok", style: .default) { (_) in
            self.dismiss(animated: true) {
                self.navigationController?.popViewController(animated: true)
            }
        }
        
        alert.addAction(alertAction)
        
        present(alert, animated: true, completion: nil)
    }

我也尝试过：

  let controller = ViewController()             
controller?.popViewController(animated: true)

Answer 1

我创建了两个ViewControllers VC1和VC2。 VC1具有导航控制器，并且VC2在VC1顶部推动是导航堆栈。在VC2中，显示了警报，并在OK按钮的点击中弹出并从导航堆栈中删除。对我来说很好。
VC1的代码：

class ViewController: UIViewController {

override func viewDidLoad() {
    super.viewDidLoad()
  self.navigationController?.pushViewController(storyboard?.instantiateViewController(withIdentifier: "SecViewController") as? SecViewController ?? SecViewController(), animated: true)
}
}

VC2的代码：

class SecViewController: UIViewController {

override func viewDidLoad() {
    super.viewDidLoad()

    showMessage(withTitle: "title", message: "Message")
}


func showMessage(withTitle title: String, message: String) {
    
    let alert = UIAlertController(title: title, message: message, preferredStyle: .alert)
    
    let alertAction = UIAlertAction(title: "ok", style: .default) { (_) in
        self.dismiss(animated: true) {
            self.navigationController?.popViewController(animated: true)
        }
    }
    
    alert.addAction(alertAction)
    
    present(alert, animated: true, completion: nil)
}