JavaScriptInterface

UIWebview extension help you to call native code from Javascript in the iOS application. Written by Swift 3.0. It's similar WebView.addJavascriptInterface in the Android application.

Setting your project

Step 1: Expand the Link Binary With Libraries section and add the following item: JavaScriptCore.framework

Step 2:

• Define a protocol, inherit from JSExport protocol, which contains these native functions as you want to work with JavaScript. For example:

@objc protocol MyExport : JSExport
{
    func check(_ message : String)
    func sayGreeting(_ message: String, _ name: String)
    func anotherSayGreeting(_ message: String, name: String)
    func showDialog(_ title: String, _ message : String)
}

Step 3: Define a class to implement native functions above.

class JSInterface : NSObject, MyExport
{
    func check(_ message: String) {
        print("JS Interface works!")
    }
    
    func sayGreeting(_ message: String, _ name: String)
    {
        print("sayGreeting: \(message): \(name)")
    }
    
    func anotherSayGreeting(_ message: String, name: String)
    {
        print("anotherSayGreeting: \(message): \(name)")
    }

    func showDialog(_ title: String, _ message : String)
    {
        dispatch_async(dispatch_get_main_queue(), {
            UIAlertView(title: title, message: message, delegate: nil, cancelButtonTitle: "OK").show()
        })
    }
}

Step 4: Create an outlet to the webview in your view controller

@IBOutlet weak var webView : UIWebView!

Step 5: Add java script interface as below at viewDidLoad:

self.webView.addJavascriptInterface(JSInterface(), forKey: "Native");

##Usage Now to call those native functions above from JavaScipt is loaded your webview, just call:

Native.check()

Native.sayGreeting('Hello', 'JavaScript Interface')