将文件拖动到Cocoa的WKWebView上的可拖动视图时，光标没有正确更改

Question

I wrote the following code to put a draggable view on WKWebView.
With this code, I expected a "+" icon will be displayed nearby a cursor when I dragged a file to the view.

class ViewController: NSViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        let rect = NSRect(x: 0, y: 0, width: 200, height: 200)

        let webView = WKWebView(
            frame: rect,
            configuration: WKWebViewConfiguration())
        webView.load(URLRequest(
            url: URL(string: "https://i.imgur.com/D5ru3Q7.jpg")!))

        let draggableView = DraggableView(frame: rect)
        draggableView.registerForDraggedTypes([.fileURL])

        self.view.addSubview(webView)
        self.view.addSubview(draggableView)
    }
}

class DraggableView: NSView {
    override func draggingEntered(_ sender: NSDraggingInfo) -> NSDragOperation {
        return .copy
    }
}

The result is here:

• Sometimes the cursor changes to a magnifying glass (same as a mouse over behavior on WKWebView).
• And sometimes "+" icon is shown.

I think the webView prevents the cursor changing. So I tried the followings. But I couldn't fix.

• Overriding hitTest of the webView worked only for non-dragging mouse over actions. But not for dragging.
• webView.unregisterDraggedTypes() didn't work.

Is there anyway to fix this?

Answer 1

Found a solution:

for t in webView.trackingAreas {
    webView.removeTrackingArea(t)
}

I think removing tracking areas on a web view is not a good idea. But at least it satisfies my need.