com.vaadin.event.dd.
Interface DropHandler
All Superinterfaces:
- extends Serializable
public interface DropHandler
DropHandlers contain the actual business logic for drag and drop operations.
The drop(DragAndDropEvent)
method is used to receive the transferred
data and the getAcceptCriterion()
method contains the (possibly
client side verifiable) criterion whether the dragged data will be handled at
all.
Since:
6.3
Method Summary | |
---|---|
void |
drop(DragAndDropEvent event)
Drop method is called when the end user has finished the drag operation on a DropTarget and DragAndDropEvent has passed
AcceptCriterion defined by getAcceptCriterion() method. |
AcceptCriterion |
getAcceptCriterion()
Returns the AcceptCriterion used to evaluate whether the
Transferable will be handed over to
drop(DragAndDropEvent) method. |
Method Detail |
---|
drop
void drop(DragAndDropEvent event)
- Parameters:
event
- the event related to this drop
Drop method is called when the end user has finished the drag operation
on a DropTarget
and DragAndDropEvent
has passed
AcceptCriterion
defined by getAcceptCriterion()
method.
The actual business logic of drag and drop operation is implemented into
this method.
getAcceptCriterion
AcceptCriterion getAcceptCriterion()
- Returns:
- the
AcceptCriterion
Returns the AcceptCriterion
used to evaluate whether the
Transferable
will be handed over to
drop(DragAndDropEvent)
method. If client side can't
verify the AcceptCriterion
, the same criteria may be tested also
prior to actual drop - during the drag operation.
Based on information from AcceptCriterion
components may display
some hints for the end user whether the drop will be accepted or not.
Vaadin contains a variety of criteria built in that can be composed to
more complex criterion. If the build in criteria are not enough,
developer can use a ServerSideCriterion
or build own custom
criterion with client side counterpart.
If developer wants to handle everything in the
drop(DragAndDropEvent)
method, AcceptAll
instance can be
returned.