多个uitextview.becomeFirstResponder在调用时无法正常工作

Question

我正在尝试使用全视图大小的单元格创建一个集合视图，该单元格在每个单元格（视图）上都有文本字段。这将是我的应用程序的注册页面。每次我翻转单元格/页面（这是一个完整的视图），我希望单元格中的textview变为活动状态，键盘弹出，键入文本以写入单元格的textview。 一切正常，直到我回到上一页，然后单元格中的文本视图不再变为活动状态。这是因为我的.becomeFirstResponder（）返回false，尽管我的情况正确。

这是我的代码

var currentPage: Int {
        set(newValue){
        if newValue <= 0 {curPg = 0}
        else if newValue >= book.count  {curPg = book.count - 1}
        else {curPg = newValue}

        switch newValue {
        case 0:
            refreshButtonSettings()

            nextButton.addTarget(self, action: #selector(nextPage), for: .touchUpInside)

            backButton.addTarget(self, action: #selector(cancel), for: .touchUpInside)
            backButton.setTitle("Cancel", for: .normal)

            personName.becomeFirstResponder()
            personName.isUserInteractionEnabled = true

        case 1:
            defaultButtonSettings()
            birthDate.becomeFirstResponder()

        case 2:
            defaultButtonSettings()

            nextButton.isEnabled = false
            nextButton.alpha = 0.5

            userName.becomeFirstResponder()

        case 3:
            defaultButtonSettings()

            passWord.becomeFirstResponder()

        case 4:
            defaultButtonSettings()
            phoneNumber.becomeFirstResponder()

        case book.count-1:
            refreshButtonSettings()

            email.becomeFirstResponder()

            backButton.addTarget(self, action: #selector(previousPage), for: .touchUpInside)
            backButton.setTitle("< ", for: .normal)

            nextButton.addTarget(self, action: #selector(sendEmailVerification), for: .touchUpInside)

        default:
            return
        }
        print(personName.isFirstResponder)
        print(birthDate.isFirstResponder)
        print(userName.isFirstResponder)
        print(passWord.isFirstResponder)
        print(phoneNumber.isFirstResponder)
        print(email.isFirstResponder)

    }
    get {
        return curPg
    }
}


func defaultButtonSettings(){
    refreshButtonSettings()

    nextButton.addTarget(self, action: #selector(nextPage), for: .touchUpInside)

    backButton.addTarget(self, action: #selector(previousPage), for: .touchUpInside)
    backButton.setTitle("< ", for: .normal)
}


func refreshButtonSettings(){
    nextButton.removeTarget(nil, action: nil, for: .allEvents)
    backButton.removeTarget(nil, action: nil, for: .allEvents)

    nextButton.isEnabled = true
    nextButton.alpha = 1
}