Cocoa touch 为什么不是'；当我在swift中点击UITextField内部时，UIKeyboard是否出现？

这和斯威夫特有关吗

我已经设置了一个控制器，没有任何与另一个控制器的连接，但它是使用它的故事板ID实例化的

关联类文件：

import Foundation
import UIKit

class SignUpViewController : UIViewController, UITextFieldDelegate {
    @IBOutlet weak var companyField: UITextField!
    @IBOutlet weak var emailField: UITextField!
    @IBOutlet weak var passwordField: UITextField!


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

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

    }


    @IBAction func loginButtonTapped(sender: UIButton) {

    }

    @IBAction func forgotPasswordButtonTapped(sender: UIButton) {
    }


    @IBAction func signUpButtonTapped(sender: UIButton) {
    }

}

@IBAction func signUpButtonTapped(sender: UIButton) {
    let signUpViewController = self.storyboard?.instantiateViewControllerWithIdentifier("signUpViewControllerSB") as SignUpViewController

    self.presentViewController(signUpViewController, animated: true, completion: nil)
} 

这是我演示注册控制器的方式：

import Foundation
import UIKit

class SignUpViewController : UIViewController, UITextFieldDelegate {
    @IBOutlet weak var companyField: UITextField!
    @IBOutlet weak var emailField: UITextField!
    @IBOutlet weak var passwordField: UITextField!


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

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

    }


    @IBAction func loginButtonTapped(sender: UIButton) {

    }

    @IBAction func forgotPasswordButtonTapped(sender: UIButton) {
    }


    @IBAction func signUpButtonTapped(sender: UIButton) {
    }

}

@IBAction func signUpButtonTapped(sender: UIButton) {
    let signUpViewController = self.storyboard?.instantiateViewControllerWithIdentifier("signUpViewControllerSB") as SignUpViewController

    self.presentViewController(signUpViewController, animated: true, completion: nil)
} 

我点击任何文本字段，得到闪烁的光标，但没有键盘出现

我错过了什么

在使用swift之前，我只需添加文本字段，运行模拟器，键盘就会弹出

---

我确信我做的每件事都是正确的

检查这些设置。转到 iOS模拟器->硬件->键盘->切换软件键盘 也

iOS模拟器->硬件->键盘->取消选中

连接硬件键盘