Can I Drag from a non-palette into a Diagram

I have a grid control on the web page with the diagram.
I’d like the user to be able to drag from a row in my grid into the diagram.

What events do I need to override or listen for to get a “can drag” event?

Is it something on the ToolManager instance itself?

I’ve tried dragging from an html link, and it shows the “can’t drop” symbol as I try.
I’m watching all Diagram events, but don’t see anything firing.

Take a look at:

Thanks Walter! I looked around but didn’t see that.