Swift 向视图控制器发送多个对象

Question

我正在尝试将多个对象从我的初始视图控制器发送到我的Username VC。这是来自我的控制器的 segue 代码：当我添加代码以发送第二个对象 termreport 时，问题就出现了。如果我删除termsM 和作业，它会像往常一样发送学生，但我还需要发送termReport 对象。我该如何解决这个问题？

ViewControler：

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    guard let students = sender as AnyObject as? [Student]
    else { return }
    guard let termsM = sender as AnyObject as? [TermReport] //How would I send both objects?
    else { return }
    if let secondVC = segue.destination as? UsernameVC {
        secondVC.students = students
        secondVC.userWebView = webView
        secondVC.terms = termsM // not sending
    }
    let gradeResponse = try Parser(innerHTML)
    self.performSegue(withIdentifier: "ShowStudents", sender: gradeResponse.students)
    self.performSegue(withIdentifier: "ShowStudents", sender: gradeResponse.termReports) //how would I send both variables?

用户名VC：

var terms: [TermReport]!
override func viewDidLoad() {
    print("TERM \(terms[0].grades[3])")//returns found nil optional ERROR
}

Answer 1

您必须使用 segue 将要发送到另一个 ViewController 的所有变量包含到单个对象中（也可以是一个集合）。您可以创建一个自定义类/结构，该类/结构具有类型为 [Student] 和 [TermReport] 的属性，或者将它们放入本机集合（元组或字典）中。

创建自定义结构：

struct TermData {
   var students = [Student]()
   var termReports = [TermReport]()
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    guard let segueData = sender as? TermData
    else { return }
    if let secondVC = segue.destination as? UsernameVC {
        secondVC.students = segueData.students
        secondVC.userWebView = webView
        secondVC.terms = segueData.termReports
        }
}     

let gradeResponse = try Parser(innerHTML)
let termData = TermData(students: gradeResponse.students, termReports: gradeResponse.termReports)
self.performSegue(withIdentifier: "ShowStudents", sender: termData)