SwiftUI Journey Part 9: WKNavigationDelegate
Next on the task is how to extend the class WKNavigationDelegate so I can call the evaluateJavascript() function.
We used an ' extension' in our existing iOS app using UIKit. But I found out, that this won’t work when using SwiftUI.
extension MyJobsViewController: WKNavigationDelegate {
}
After further Googling, research and internet digging I learned that I need to use makeCoordinator() function.
Creates the custom instance that you use to communicate changes from your view controller to other parts of your SwiftUI interface.
First, I wrote an inner class called Coordinator.
class Coordinator: NSObject, WKNavigationDelegate {
let parent: OnlineJobsWebView
init(_ parent: OnlineJobsWebView) {
self.parent = parent
}
func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
webView.evaluateJavaScript(Keys.javascriptRemoveElements, completionHandler: {
_, error in
})
}
}
Then in the main class
struct OnlineJobsWebView: NSViewRepresentable {
func makeCoordinator() -> Coordinator {
Coordinator(self)
}
var url: URL
func makeNSView(context: Context) -> WKWebView {
return WKWebView()
}
func updateNSView(_ webView: WKWebView, context: Context) {
webView.navigationDelegate = context.coordinator
// Evaluate Javascript will now work at this point.
}
}
This implementation feels a little hacky. Why wouldn’t Apple just introduce a WebView for SwiftUI? Going through all this is just painful.
