WKWebView xmlhttprequest with file url

Question

I am migrating from UIWebView to WKWebView with my local HTMLs in the app documents folder. I can load the index page with all css and js files, but every ajax call (xmlhttprequ

Answer 1

So the accepted was not working for me when I first tried it (I was doing it wrong at the time) and the bug about (https://bugs.webkit.org/show_bug.cgi?id=154916) it strongly recommends against doing it. My solution was to implement a custom url scheme and use that to load all files. Looks like this.

First creating the WKWebView to which the url scheme is attached (you must create the WKWebView yourself, it can't be created on a storyboard).

override func viewDidLoad() {

    let configuration = WKWebViewConfiguration()
    configuration.setURLSchemeHandler(PrayerAssetHandler(), forURLScheme: "x-file")

    webview = WKWebView(frame: webContentView.bounds, configuration: configuration)
    self.webContentView.addSubview(webview!)
    webview?.autoresizingMask = webContentView.autoresizingMask
    webview!.navigationDelegate = self

    super.viewDidLoad()
}

Then implement the handler.

import Foundation
import WebKit
import MobileCoreServices

class PrayerAssetHandler: NSObject, WKURLSchemeHandler {

    func webView(_ webView: WKWebView, start urlSchemeTask: WKURLSchemeTask) {
        let url = urlSchemeTask.request.url!

        let pathArr = url.path.components(separatedBy: ".")
        let forResource: String = pathArr[0]
        let ofType: String? = pathArr.count > 1 ? pathArr[1] : nil

        let bundlePath = Bundle.main.path(forResource: "data_sub_folder" + forResource, ofType: ofType)

        let fileExtension: CFString = ofType! as CFString
        guard
            let extUTI = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension,
                                fileExtension, nil)?.takeUnretainedValue()
        else { return }

        guard
            let mimeUTI: NSString = UTTypeCopyPreferredTagWithClass(extUTI,
                                kUTTagClassMIMEType)?.takeRetainedValue()
        else { return }

        let mimeType: String = mimeUTI as String

        do {
            let data: Data = try NSData(contentsOfFile: bundlePath!) as Data

            //Create a NSURLResponse with the correct mimetype.
            let urlResponse = URLResponse(url: url, mimeType: mimeType,
                                          expectedContentLength: data.count, textEncodingName: "utf8")
            urlSchemeTask.didReceive(urlResponse)
            urlSchemeTask.didReceive(data)
            urlSchemeTask.didFinish()
        }  catch _ as NSError {
            return
        }

    }

    func webView(_ webView: WKWebView, stop urlSchemeTask: WKURLSchemeTask) {
    }
}