How to access goBack and goForward via UIViewRepresentable

问题

I have added a WKwebview in SwiftUI via UIVewRepresentable. I am having difficulties getting some buttons to make the web view go back and go forward. Below is the two classes I have made but I am not even getting print to work ( maybe a bug? ).

import SwiftUI

import WebKit

struct Webview : UIViewRepresentable {

let request: URLRequest

func makeUIView(context: Context) -> WKWebView  {
    return WKWebView()
}

func updateUIView(_ uiView: WKWebView, context: Context) {
    uiView.load(request)
}

func goBack(){
    // go back
    print("go back")
}

func goForward (){
    // go forward
    print("go forward")
}
}



import SwiftUI

struct FullWebView : View {

let webview = Webview(request: URLRequest(url: URL(string: "https://www.apple.com")!))

var body: some View {
    VStack{
        HStack{
            Button(action: {
                //do something
                self.webview.goBack()
            }){
                Text("back")
            }

            Spacer()

            Button(action: {
                //do something
                self.webview.goForward()
            }){
                Text("forward")
            }

        }

        webview
    }
}
}

回答1:

dfd thank you for pointing me on the correct path, your answer needed a little modification because adding the webview as a var to the struct means I needed to set a value on it when I use it, so I also had to add a custom init method. Anyway here is the code that works.

Webview struct

import SwiftUI

import WebKit

struct Webview : UIViewRepresentable {


    let request: URLRequest
    var webview: WKWebView?

    init(web: WKWebView?, req: URLRequest) {
        self.webview = WKWebView()
        self.request = req
    }

    func makeUIView(context: Context) -> WKWebView  {
        return webview!
    }

    func updateUIView(_ uiView: WKWebView, context: Context) {
        uiView.load(request)
    }

    func goBack(){
        webview?.goBack()
    }

    func goForward(){
        webview?.goForward()
    }
  }

and here is the struct using the webview and adding the buttons to the top

import SwiftUI

struct FullWebView : View {


let webview = Webview(web: nil, req: URLRequest(url: URL(string: "https://www.apple.com")!))

var body: some View {
    VStack{
        HStack{
            Button(action: {
                //do something
                self.webview.goBack()
            }){
                Text("back")
            }

            Spacer()

            Button(action: {
                //do something
                self.webview.goForward()
            }){
                Text("forward")
            }

        }

        webview
    }
}
}

来源：https://stackoverflow.com/questions/56760092/how-to-access-goback-and-goforward-via-uiviewrepresentable

标签

wkwebview

swiftui

ios13