The 'onDragOver' callback

Event generated under Windows only

Event number: 33
Valid for: Any visible control

The onDragOver callback is invoked for the target control when a potential drag-and-drop operation has begun, and the user moves the mouse over the target control. (A potential drag-and-drop operation occurs when the user drags a source control onto a target control and the sourceformats property of the source is compatible with the targetformats property of the target, but before the user releases the mouse to complete the operation).

It will typically be preceded by an onDragEnter event, and possibly followed by an onDragLeave or onDragDrop event.

The dragsource property will contain the name of the control being dragged.

The event-specific parameters in ⎕EV are (in index origin 1):

    ⎕EV[6]   The 'tie' property value of the source control being dragged