Receiving drag events in a WebView in a QML application

Receiving drag events in a WebView in a QML application

I'm working on an app using QML and the Ubuntu SDK. One of the Pages
contains a WebView. While the WebView receives click events just fine, it
doesn't receive drag events, as I would like it to.
I assume the problem is that drag events are being trapped to provide
navigation gestures for the WebView. This isn't necessary: The WebView is
sized to exactly fill up the available space. In the HTML displayed by the
WebView, I set <meta name="viewport" content="initial-scale=1.0,
user-scalable=no">, to keep the WebView from allowing zooming. The content
is sized to fill up the viewport, so there's no need for scrolling. But
still, no drag events come through to the WebView. What do I need to do to
let them through?