public abstract class DropTargetAdapter extends Object implements DropTargetListener
Extend this class to create a DropTargetEvent
listener
and override the methods for the events of interest. (If you implement the
DropTargetListener
interface, you have to define all of
the methods in it. This abstract class defines a null implementation for
every method except drop(DropTargetDropEvent)
, so you only have
to define methods for events you care about.) You must provide an
implementation for at least drop(DropTargetDropEvent)
. This
method cannot have a null implementation because its specification requires
that you either accept or reject the drop, and, if accepted, indicate
whether the drop was successful.
Create a listener object using the extended class and then register it with
a DropTarget
. When the drag enters, moves over, or exits
the operable part of the drop site for that DropTarget
, when
the drop action changes, and when the drop occurs, the relevant method in
the listener object is invoked, and the DropTargetEvent
is
passed to it.
The operable part of the drop site for the DropTarget
is
the part of the associated Component
's geometry that is not
obscured by an overlapping top-level window or by another
Component
higher in the Z-order that has an associated active
DropTarget
.
During the drag, the data associated with the current drag operation can be
retrieved by calling getTransferable()
on
DropTargetDragEvent
instances passed to the listener's
methods.
Note that getTransferable()
on the
DropTargetDragEvent
instance should only be called within the
respective listener's method and all the necessary data should be retrieved
from the returned Transferable
before that method returns.
DropTargetEvent
,
DropTargetListener
Constructor and Description |
---|
DropTargetAdapter() |
Modifier and Type | Method and Description |
---|---|
void |
dragEnter(DropTargetDragEvent dtde)
Called while a drag operation is ongoing, when the mouse pointer enters
the operable part of the drop site for the
DropTarget
registered with this listener. |
void |
dragExit(DropTargetEvent dte)
Called while a drag operation is ongoing, when the mouse pointer has
exited the operable part of the drop site for the
DropTarget registered with this listener. |
void |
dragOver(DropTargetDragEvent dtde)
Called when a drag operation is ongoing, while the mouse pointer is still
over the operable part of the drop site for the
DropTarget
registered with this listener. |
void |
dropActionChanged(DropTargetDragEvent dtde)
Called if the user has modified
the current drop gesture.
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
drop
public void dragEnter(DropTargetDragEvent dtde)
DropTarget
registered with this listener.dragEnter
in interface DropTargetListener
dtde
- the DropTargetDragEvent
public void dragOver(DropTargetDragEvent dtde)
DropTarget
registered with this listener.dragOver
in interface DropTargetListener
dtde
- the DropTargetDragEvent
public void dropActionChanged(DropTargetDragEvent dtde)
dropActionChanged
in interface DropTargetListener
dtde
- the DropTargetDragEvent
public void dragExit(DropTargetEvent dte)
DropTarget
registered with this listener.dragExit
in interface DropTargetListener
dte
- the DropTargetEvent
Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2012, Oracle and/or its affiliates. All rights reserved.