/**
* Start a drag operation on the given element.
*
* @param element The element to drag
*/
public void dragStart(DnDInfo info) {
// cache a placeholder where the element started (NOTE: this also prevents the parent from
// being auto-removed by going 'empty'
if (dragElement.getParent() != null) {
if (dragElement instanceof MStackElement)
dragPH = AdvancedFactoryImpl.eINSTANCE.createPlaceholder();
else if (dragElement instanceof MPartStack)
dragPH = BasicFactoryImpl.eINSTANCE.createPartSashContainer();
else if (dragElement instanceof MTrimElement)
dragPH = MenuFactoryImpl.eINSTANCE.createToolControl();
dragPH.setElementId(DRAG_PLACEHOLDER_ID);
dragPH.setToBeRendered(false);
List<MUIElement> kids = dragElement.getParent().getChildren();
kids.add(kids.indexOf(dragElement), dragPH);
}
dropAgent = dndManager.getDropAgent(dragElement, info);
if (dropAgent != null) dropAgent.dragEnter(dragElement, info);
}
