UIViewControllers 共享“通用”IBAction

Question

我有一个带有 6 个UIViewControllers 的应用程序。

任何viewcontroller 都具有这样的功能：

@IBAction func onHelp(_ sender: UIBarButtonItem) {

        DispatchQueue.main.async(execute: { () -> Void in
            let helpVC =  self.storyboard?.instantiateViewController(withIdentifier: "Help") as! HelpViewController
            helpVC.starter = "MapHelp"
            helpVC.helpSubtitle = "Map"
            self.present(helpVC, animated: true, completion: nil)
        })

    }

任何viewcontroller 中的任何IBAction 都呈现相同的HelpViewController，但传递不同的参数（starter 和helpSubtitle）。

由于我不喜欢重复代码，首先我认为应该将这个函数转换为更通用的东西。

但是：有没有办法创建一个通用的IBAction，适用于每个viewcontroller？

Answer 1

创建一个 BaseViewController 并在其中添加通用方法。

class BaseViewController: UIViewController {



override func viewDidLoad() {
        super.viewDidLoad()

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

    func genericMethod(starter: String, helpSubtitle: String){
        let helpVC =  self.storyboard?.instantiateViewController(withIdentifier: "Help") as! HelpViewController
        helpVC.starter = starter
        helpVC.helpSubtitle = helpSubtitle
        self.present(helpVC, animated: true, completion: nil)
    }

    @IBAction func onHelp(_ sender: UIButton?) {
       //You can use this method as generic IBaction if you want. It can be connected to buttons of all child View Controllers. But doing so will limit your param sending ability. On the plus side though, you won't have to define an IBAction everywhere and you can simply connect your child VC's button to Parent Class' IBAction.
    }

}

现在从这个类继承你的 ViewControllers，比如：

import UIKit

class ViewController: BaseViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
    }

    @IBAction func btnTapped(_ sender: Any) {
        genericMethod(starter: "View Controller", helpSubtitle: "I was triggered from VC1")
    }

}

和

import UIKit

class SecondViewController: BaseViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

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

    @IBAction func btnTapped(_ sender: Any) {
        genericMethod(starter: "View Controller 2", helpSubtitle: "I was triggered from VC2")
    }

}

就是这样。您的两个 ViewController 都可以调用父方法。如果您仍想使用通用 IBAction，您也可以这样做，但我不建议您使用该课程，因为您想传递可以变化的参数。如果你想这样做，它看起来像这样：

请记住，这里的 ViewController 是从基础 ViewController 继承的，这就是它可以访问父类中定义的 IBActions 的原因。您所要做的就是拖动和连接。