Question

我正在尝试将数据传递给第二个视图控制器，但没有成功这是我的代码：

let storyboard = UIStoryboard(name: "Main", bundle: nil)
let vc = storyboard.instantiateViewController(withIdentifier: “secondVC")
self.present(vc, animated: true, completion: nil)

//The following solution as I checked in the previous questions doesn't work:

vc.Var1InSecondViewController = self.var1
vc.Var2InSecondViewController = self.var2

声称与第二个视图控制器相关的'vc'没有'Var1InSecondViewController'的成员，即使我在第二个视图控制器中创建了它。

非常感谢您的帮助。谢谢。

Answer 1

您必须按如下方式指定secondVC的类名才能访问其属性

而不是，

let vc = storyboard.instantiateViewController(withIdentifier: “secondVC")

使用

let vc = storyboard.instantiateViewController(withIdentifier: “secondVC") as? YOUR_SECOND_VIEW_CONTROLLER_CLASS_NAME

在呈现视图控制器之前执行分配步骤，如下所示

vc?.Var1InSecondViewController = self.var1
vc?.Var2InSecondViewController = self.var2
self.present(vc!, animated: true, completion: nil)

Answer 2

您可以使用：

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "yourSegue" {
        if let firstViewController = segue.destination as? FirstViewController {
          firstViewController.var1 = var1
        }
    }
}
}

如何以编程方式导航到ViewController并传递数据

2 个答案: