如何从不继承 UIviewController 的类（从带有 class 的 swift 文件）加载 UIViewController？

Question

我正在为一个小部件构建框架。我有两个文件如下： widgetBuilder.swift 和 webWidget.swift

widgetBuilder.swift 是带有 getter 和 setter 的文件，它从将要使用这个小部件框架的应用程序中获取某些值。

来自widgetBuilder.swift的代码

import Foundation
class WidgetBuilder {

    private var userId: String!
    private var emailId: String!

    public func setuserId(userId: String) -> WidgetBuilder{
        self.userId = userId
        return self
    } 

    public func setEmailId(emailId: String) -> WidgetBuilder{
        self.emailId = emailId
        return self

    }

    public func build() -> WidgetBuilder{
        // Wanted to load the webview from here 
    }
}

初始化完成后我会调用构建函数，我想加载webWidget.swift的ViewController

来自webWidget.swift的代码

class webWidget: UIViewController, WKUIDelegate, WKNavigationDelegate  {


    var webView: WKWebView!

    override func loadView() {
        webView = WKWebView()
        webView.uiDelegate = self
        webView.navigationDelegate = self
        view = webView
        self.loadWebView()
    }

    public func loadWebView(){
        let url = URL(string: "https://www.google.com")!
        webView.load(URLRequest(url: url))
        webView.allowsBackForwardNavigationGestures = true
    }

    public func loadWidgetScreen() {
        //Something is not correct here  
        let storyboard = UIStoryboard(name: "Main", bundle: nil)
        let controller = storyboard.instantiateViewController(withIdentifier: "WidgetController") 
        self.present(controller, animated: true, completion: nil)
    }

}

如何从widgetBuilder.swift 加载 webWidget 视图并传递一些数据？

Answer 1

这就是我解决的方法，发布它可能对希望从 swift 文件加载 ViewController 的人有所帮助。

一旦我从我的 swift 文件中调用 build()，它就必须加载视图，

添加了一个var，它从想要加载此小部件的父视图中获取 ViewController 实例。

widgetBuilder.swift里面

private var clientView: UIViewController?

public init(_ viewController:UIViewController){
    self.clientView = viewController;
}

那么，

public func build(){

    // Widget() creates ViewController instance , this viewcontroller is mapped to a widget.xib file
    let controller: UIViewController = Widget() // Creating the instance of the view class
    self.clientView?.addChild(controller) // self.clientView is the ViewController instance that wants to load widget view 
    self.clientView?.view.addSubview(controller.view)
    controller.view.frame = (clientView?.view.bounds)!
    controller.view.autoresizingMask = [.flexibleWidth, .flexibleHeight]
    controller.didMove(toParent: clientView)
}

Answer 2

在 webWidget.swift 中 用下面替换你的 loadWidgetScreen() 方法

public func loadWidgetScreen() {
  if var topController = UIApplication.sharedApplication().keyWindow?.rootViewController {
      while let presentedViewController = topController.presentedViewController {
          topController = presentedViewController
      }

      // topController should now be your topmost view controller
      let storyboard = UIStoryboard(name: "Main", bundle: nil)
      let controller = storyboard.instantiateViewController(withIdentifier: "WidgetController") 
      self.present(controller, animated: true, completion: nil)
  }
  else {
    print("topViewController not found")
  }
}