I am creating a basic screen designer where you can drag elements from a palate onto a "canvas" (nothing to do with html 5) or re-sort the existing elements on the canvas.

I am displaying the elements on the canvas using "sortable" columns. Is there a way to trigger all the possible drop zones on a sortable to show themselves (when an element is being sorted or dragged) since at the moment, when I move a sortable element over the canvas the drop zones are expanding and contracting which moves all the other elements around and makes it difficult to target the correct drop zone.

Thanks.