how to get mouse over URLs into WkWebView with Swift

Question

As a follow-up to How do I get the selected text from a WKWebView from objective-C, I have a related question but using Swift.

I need to obtain the URL on mouse over, in prelude to contextual menu appearance, so I can inject it into the menu item's respresentedObject - or otherwise save. The built-in action(s) for some items are not being properly handled.

I find that menu item action for 'Open Link' works fine but not for 'Open Link in New Window'; neither of these work via the built-in contextual menu item actions. I wanted to support a middle button click to be the latter menu item.

So, using the original post as a base I have this - I also sub-class WkWebView, adding

class MyWebView : WKWebView {
    var selectedText : String?
    var selectedURL : URL?
}

then in view controller

func viewDidLoad() {
    //  Watch javascript selection messages
    let controller = webView.configuration.userContentController
    controller.add(self, name: "newSelectionDetected")
    let js = """
function getSelectionAndSendMessage()
{
    var txt = document.getSelection().toString() ;
    window.webkit.messageHandlers.newSelectionDetected.postMessage(txt) ;
}
document.onmouseup   = getSelectionAndSendMessage ;
document.onkeyup     = getSelectionAndSendMessage ;
"""

    let script = WKUserScript.init(source: js, injectionTime: .atDocumentEnd, forMainFrameOnly: true)
    controller.addUserScript(script)
}

// MARK: Javascript

func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
    Swift.print("userContentController")

    // A new selected text has been received
    if let urlString : String = message.body as? String
    {
        webView.selectedText = urlString
        Swift.print("ucc: str -> \(urlString)")
    }
    if let url = message.frameInfo.request.url {
        webView.selectedURL = url
        Swift.print("ucc: url -> \(url.absoluteString)")
    }
}

// MARK: callbacks
override func willOpenMenu(_ menu: NSMenu, with event: NSEvent) {

    //  Pick off javascript items we want to ignore or handle
    for title in ["Open Link", "Open Link in New Window", "Download Linked File"] {
        if let item = menu.item(withTitle: title) {
            if title == "Download Linked File" {
                menu.removeItem(item)
            }
            else
            if title == "Open Link"
            {
                item.representedObject = self.window
                item.action = #selector(MyWebView.openLinkInWindow(_:))
                item.target = self
            }
            else
            {
                item.action = #selector(MyWebView.openLinkNewWindow(_:))
                item.target = self
            }
        }
    }
}

In my action handler, I'm only getting the frame's URL, not what was highlighted on mouse over.

What I need, is to get the URL etc as shown in a web browser's status bar on mouse overs to be cached for a contextual menu item's action.

score 1 · Accepted Answer · answered Aug 17 '18 at 16:16

Well, I guess that, in your javascript, you need to add a onmouseover event handler to all your links, and this event handler should send the link back to the swift world.

Building upon your code, I would add in the Javascript something like:

function sendLink()
{
    window.webkit.messageHandlers.newUrlDetected.postMessage(this.href) ;
}

var allLinks = document.links;
for(var i=0; i< allLinks.length; i++)
{
    allLinks[i].onmouseover = sendLink ;
}

And of course, in the Swift world, you need to catch the "newUrlDetected"

controller.add(self, name: "newUrlDetected")

And in the Swift message handler, you need to switch upon the WKScriptMessage name property.

If it is "newSelectionDetected", then set webView.selectedText with the message body
If it is "newUrlDetected", then set webView.selectedURL with the message body

how to get mouse over URLs into WkWebView with Swift

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