swift - 选择UITableView中的单个单元格即可转到UITableView显示不同的学生列表数据

Question

已更新

我想选择每一行转到 ViewController，该 ViewController 有一个 TableView 来显示不同的学生列表数据，但对于我的代码，它将显示与我创建新学生对象相同的列表，如何解决此问题？问题是我前面没有学生数据列表，直到我单击单个类单元格转到下一个 ViewController，然后我将有一个加号按钮将学生添加到 TableView 中。

ManageViewController类:

class ManageViewController : UIViewController, UITableViewDataSource, UITableViewDelegate{

@IBOutlet weak var tableView: UITableView!

var classList = [Class]()
var selectedClass: StudentData?


override func viewDidLoad() {
    super.viewDidLoad()

    self.navigationItem.title = "Manage Classes"
    tableView.dataSource = self

    let fetchRequest: NSFetchRequest<Class> = Class.fetchRequest()

    do {
        let classList = try PersistenceService.context.fetch(fetchRequest)
        self.classList = classList
        self.tableView.reloadData()
    } catch {}


    // Do any additional setup after loading the view.
}

添加类按钮操作:

@IBAction func onAddTapped(_ sender: UIBarButtonItem) {
    let alert = UIAlertController(title: "Add Class", message: nil, preferredStyle: .alert)
    alert.addTextField { (classListTF) in
        classListTF.placeholder = "Enter Class"
    }
    alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
    let action = UIAlertAction(title: "Add", style: .default) { (_) in
        guard let list = alert.textFields?.first?.text else { return }
        print(list)
        let subject = Class(context: PersistenceService.context)
        subject.class_name = list
        PersistenceService.saveContext()
        self.classList.append(subject)
        self.tableView.reloadData()
    }
    alert.addAction(action)
    present(alert, animated: true)
}

类单元选择代码:

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    let cell = tableView.cellForRow(at: indexPath)

    // Unwrap that optional
    if let label = cell?.textLabel?.text {
        print("Tapped \(label)")
    }
    self.performSegue(withIdentifier: "studentInfoView", sender: self)
}

StudentListViewController 类:

class StudentListViewController: UIViewController, UITableViewDataSource,UITableViewDelegate {

@IBOutlet weak var tableView: UITableView!

var studentList = [StudentData]()
var selectedStudent: StudentData?

override func viewDidLoad() {
    super.viewDidLoad()

    let fetchRequest: NSFetchRequest<StudentData> = StudentData.fetchRequest()

    do {
        let studentList = try PersistenceService.context.fetch(fetchRequest)
        self.studentList = studentList
        self.tableView.reloadData()
    } catch {}


}

@IBAction func addStudentTapped(_ sender: UIBarButtonItem) {
    let alert = UIAlertController(title: "Add Student", message: nil, preferredStyle: .alert)
    alert.addTextField { (studentListTF) in
        studentListTF.placeholder = "Enter name"
    }
    alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
    let action = UIAlertAction(title: "Add", style: .default) { (_) in
        guard let student = alert.textFields?.first?.text else { return }
        print(student)
        let person = StudentData(context: PersistenceService.context)
        person.student_name = student
        PersistenceService.saveContext()
        self.studentList.append(person)
        self.tableView.reloadData()
    }
    alert.addAction(action)
    present(alert,animated: true)
}

我已经更新了 ManageViewController 类和 StudentInfoViewContrller 类的附加代码。抱歉，我是一名新的 Ios 程序员。

Answer 1

您应该添加一个附加条件，以便能够根据所选行进入不同的 View ，例如 ff:

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    let cell = tableView.cellForRow(at: indexPath)

    if indexPath.row == 0 {
        self.performSegue(withIdentifier: "toViewA", sender: self)
    } else {
        self.performSegue(withIdentifier: "toViewA", sender: self)
    }

}