ios - 核心数据: How can I update a TableView field from an alert?

Question

我有一个使用 Core Data 创建的 TableView。用户可以轻松地将新记录“添加”到 TableView 上 - 但是，我编写了一个更新函数，该函数显示更新警报，允许用户修改最近添加的字段。这是“updateContact 函数:

 func updateBusinessContact(name: String, email: String, phone: String, company: String)
{
    // create an Alert with a textFields for all ContactBusiness fields
    let alertController = UIAlertController(title: "Update Contact Business",
                                            message: "",
                                            preferredStyle: UIAlertControllerStyle.alert)

    // add the textField to the Alert. Create a closuer to handle the configuration
    alertController.addTextField(configurationHandler: {(textField: UITextField!) in
        textField.text = name
        textField.isUserInteractionEnabled = false
        textField.keyboardType=UIKeyboardType.namePhonePad
        //            textField.secureTextEntry = true    // password entry
    })

    alertController.addTextField(configurationHandler: {(textField: UITextField!) in
        textField.text = email
        textField.keyboardType=UIKeyboardType.emailAddress
    })

    alertController.addTextField(configurationHandler: {(textField: UITextField!) in
        textField.text = phone
        textField.keyboardType=UIKeyboardType.phonePad
    })

    alertController.addTextField(configurationHandler: {(textField: UITextField!) in
        textField.placeholder="Street"
        textField.keyboardType=UIKeyboardType.default
    })

    alertController.addTextField(configurationHandler: {(textField: UITextField!) in
        textField.placeholder="City"
        textField.keyboardType=UIKeyboardType.default
    })

    alertController.addTextField(configurationHandler: {(textField: UITextField!) in
        textField.text = "oh"
        textField.keyboardType=UIKeyboardType.default
    })

    alertController.addTextField(configurationHandler: {(textField: UITextField!) in
        textField.text = "44121"
        textField.keyboardType=UIKeyboardType.numberPad
    })

    alertController.addTextField(configurationHandler: {(textField: UITextField!) in
        textField.text = company
        textField.keyboardType=UIKeyboardType.default
    })

    // create a default action for the Alert
    let defaultAction = UIAlertAction(
        title: "Ok",
        style: UIAlertActionStyle.default,
        handler: {(alertAction: UIAlertAction!) in
            /// get the input from the alert controller
            let name: String = (alertController.textFields![0]).text!
            let email: String = (alertController.textFields![1]).text!
            let phone: String = (alertController.textFields![2]).text!
            let street: String = (alertController.textFields![3] ).text!
            let city: String = (alertController.textFields![4] ).text!
            let state: String = (alertController.textFields![5] ).text!
            let zip: String = (alertController.textFields![6] ).text!
            let company: String = (alertController.textFields![7]).text!

            // add Contact to the managedOBject
            _ = ContactBusiness(managedObjectContext: self.managedObjectContext,
                                name: name, email: email, phone: phone, street:street, city: city, state: state, zip: zip, company: company)


            // save the managedObject
            CoreDataHelper.addContactBusiness(managedObjectContext: self.managedObjectContext)

            // get all Contacts from CoreData
            self.cbArray = CoreDataHelper.getAllContactBusiness(managedObjectContext: self.managedObjectContext)

            // reload the data into the TableView
            self.tvContacts.reloadData()
    })

    let cancelAction = UIAlertAction(
        title: "Cancel",
        style: UIAlertActionStyle.cancel,
        handler:nil)

    // add the action to the Alert
    alertController.addAction(defaultAction)
    alertController.addAction(cancelAction)

    // display the Alert
    present(alertController, animated: true, completion: nil)
}

我相信我遇到的问题是围绕这段代码的某个地方

  // add Contact to the managedOBject
            _ = ContactBusiness(managedObjectContext: self.managedObjectContext,
                                name: name, email: email, phone: phone, street:street, city: city, state: state, zip: zip, company: company)

这可行，但它不会更新预先存在的 TableView 条目 - 它只是将另一个具有更新信息的对象添加到表中。

如何将用户修改的字段存储在 ContactBusiness 对象中？

(P.S这是一个作业)

提前致谢，我可以提供所需的任何其他信息。

Answer 1

在 TableView 的didSelectMethod上，在这里，我希望您的核心数据表的名称是 ContactBusiness(如果有其他相应更改)，

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

         currentContactBusiness = self.cbArray[indexPath.row]
        //you can call function updateBusinessContact here
    }


//Updated Function
func updateBusinessContact(name: String, email: String, phone: String, company: String, currentContactBusiness : ContactBusiness)
{
     //update the details of currentContactBusiness
}

注意:这只是伪代码，可能包含语法错误