Picture event is generated over a target graphic object when a user moves the mouse cursor over it during Drag operation.
There must be determined whether the target graphic object is able to process Drop operation. This can be done globally, if the graphic object cannot take a role of the target object, or based on the format of transferred data. The format can be get by the function %IsDragData.
If the data format is suitable for processing in the graphic object, the target object should enable Drop operation through the parameter _bAllow. Based on this value, a mouse cursor icon, which indicates the possible completion of Drop operation, will be set.