FLWKWebView.swift

import UIKit
import WebKit

@available(iOS 8.0, *)
extension WKWebView: FLWebViewProvider {
    
    // Use associated objects to set and get the request ivar
    func associatedObjectKey() -> String {
        return "kAssociatedObjectKey"
    }
    
    var request: NSURLRequest? {
        get {
            return objc_getAssociatedObject(self, associatedObjectKey()) as? NSURLRequest
        }
        set(newValue) {
            objc_setAssociatedObject(self, associatedObjectKey(), newValue, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
    }
    
    // A simple convenience initializer, this allows for WKWebView(delegateView:) initialization
    convenience init(delegateView: ViewController) {
        self.init(frame: delegateView.view.frame, configuration: WKWebViewConfiguration())
        setDelegateViews(delegateView)
    }
    
    // We will need to set both the UIDelegate AND navigationDelegate in the case of WebKit
    func setDelegateViews(viewController: ViewController) {
        self.UIDelegate = viewController as WKUIDelegate
        self.navigationDelegate = viewController as WKNavigationDelegate
    }

    func currentURL() -> NSURL? {
        return self.URL
    }
    
    func canNavigateBack() -> Bool {
        return self.canGoBack
    }
    
    func canNavigateForward() -> Bool {
        return self.canGoForward
    }
    
    // A quick method for loading requests based on strings in a URL format
    func loadRequestFromString(urlNameAsString: String!) {
        self.loadRequest(NSURLRequest(URL: NSURL(string: urlNameAsString)!))
    }
    
    func evaluateJavaScriptString(javascriptString: String!, completionHandler: (AnyObject?, NSError?) -> ()) {
        evaluateJavaScript(javascriptString, completionHandler: completionHandler)
    }
    
}