com.bbn.openmap.tools.dnd
Class DnDListener

java.lang.Object
  java.awt.dnd.DragGestureRecognizer
      java.awt.dnd.MouseDragGestureRecognizer
          com.bbn.openmap.tools.dnd.DnDListener

All Implemented Interfaces:

java.awt.dnd.DragSourceListener, java.awt.dnd.DropTargetListener, java.awt.event.MouseListener, java.awt.event.MouseMotionListener, java.io.Serializable, java.util.EventListener

Direct Known Subclasses:

DefaultDnDCatcher

public class DnDListener
extends java.awt.dnd.MouseDragGestureRecognizer
implements java.awt.dnd.DragSourceListener, java.awt.dnd.DropTargetListener

DnDListener acts as the base DnD and MouseListener class. Some of its methods should be overriden by extending classes.

See Also:

DefaultDnDCatcher, Serialized Form

Field Summary

protected int	default_action
protected boolean	startDrag

Fields inherited from class java.awt.dnd.DragGestureRecognizer

component, dragGestureListener, dragSource, events, sourceActions

Constructor Summary

protected	DnDListener(java.awt.dnd.DragSource ds) Constructs a new DnDListener given the DragSource for the Component.
protected	DnDListener(java.awt.dnd.DragSource ds, java.awt.Component c) Construct a new DnDListener given the DragSource for the Component c, and the Component to observe.
protected	DnDListener(java.awt.dnd.DragSource ds, java.awt.Component c, int act)
protected	DnDListener(java.awt.dnd.DragSource ds, java.awt.Component c, int act, java.awt.dnd.DragGestureListener dgl)

Method Summary

void	dragDropEnd(java.awt.dnd.DragSourceDropEvent dsde) This method is invoked to signify that the Drag and Drop operation is complete.
void	dragEnter(java.awt.dnd.DragSourceDragEvent dsde) Called as the hotspot enters a platform dependent drop site.
void	dragEnter(java.awt.dnd.DropTargetDragEvent dtde) Called when a drag operation has encountered the DropTarget.
void	dragExit(java.awt.dnd.DragSourceEvent dse) Called as the hotspot exits a platform dependent drop site.
void	dragExit(java.awt.dnd.DropTargetEvent dte) The drag operation has departed the DropTarget without dropping.
void	dragOver(java.awt.dnd.DragSourceDragEvent dsde) Called as the hotspot moves over a platform dependent drop site.
void	dragOver(java.awt.dnd.DropTargetDragEvent dtde) Called when a drag operation is ongoing on the DropTarget.
void	drop(java.awt.dnd.DropTargetDropEvent dtde) The drag operation has terminated with a drop on this DropTarget.
void	dropActionChanged(java.awt.dnd.DragSourceDragEvent dsde) Called when the user has modified the drop gesture.
void	dropActionChanged(java.awt.dnd.DropTargetDragEvent dtde) Called if the user has modified the current drop gesture.
java.awt.Cursor	getCursor(java.awt.Cursor default_cursor) Get the Cursor object associated with the default_cursor.
int	getDefaultAction() Returns the default DnD action.
void	setCursor(java.awt.Image img, java.awt.Cursor default_cursor) Sets a custom Cursor object associated with the default_cursor.
void	setDefaultAction(int newAction) Sets the default DnD action.

Methods inherited from class java.awt.dnd.MouseDragGestureRecognizer

mouseClicked, mouseDragged, mouseEntered, mouseExited, mouseMoved, mousePressed, mouseReleased, registerListeners, unregisterListeners

Methods inherited from class java.awt.dnd.DragGestureRecognizer

addDragGestureListener, appendEvent, fireDragGestureRecognized, getComponent, getDragSource, getSourceActions, getTriggerEvent, removeDragGestureListener, resetRecognizer, setComponent, setSourceActions

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

startDrag

protected boolean startDrag

default_action

protected int default_action

Constructor Detail

DnDListener

protected DnDListener(java.awt.dnd.DragSource ds)

Constructs a new DnDListener given the DragSource for the Component.

Parameters:

ds - the DragSource for the Component

DnDListener

protected DnDListener(java.awt.dnd.DragSource ds,
                      java.awt.Component c)

Construct a new DnDListener given the DragSource for the Component c, and the Component to observe.

Parameters:

ds - the DragSource for the Component c

c - the Component to observe

DnDListener

protected DnDListener(java.awt.dnd.DragSource ds,
                      java.awt.Component c,
                      int act)

DnDListener

protected DnDListener(java.awt.dnd.DragSource ds,
                      java.awt.Component c,
                      int act,
                      java.awt.dnd.DragGestureListener dgl)

Method Detail

dragDropEnd

public void dragDropEnd(java.awt.dnd.DragSourceDropEvent dsde)

This method is invoked to signify that the Drag and Drop operation is complete. The getDropSuccess() method of the DragSourceDropEvent can be used to determine the termination state. The getDropAction() method returns the operation that the DropTarget selected (via the DropTargetDropEvent acceptDrop() parameter) to apply to the Drop operation. Once this method is complete, the current DragSourceContext and associated resources become invalid.

Specified by:

dragDropEnd in interface java.awt.dnd.DragSourceListener

Parameters:

dsde - the DragSourceDropEvent

dragEnter

public void dragEnter(java.awt.dnd.DragSourceDragEvent dsde)

Called as the hotspot enters a platform dependent drop site. This method is invoked when the following conditions are true:

• The logical cursor's hotspot initially intersects a GUI Component's visible geometry.
• That Component has an active DropTarget associated with it.
• The DropTarget's registered DropTargetListener dragEnter() method is invoked and returns successfully.
• The registered DropTargetListener invokes the DropTargetDragEvent's acceptDrag() method to accept the drag based upon interrogation of the source's potential drop action(s) and available data types ( DataFlavor s).

Specified by:

dragEnter in interface java.awt.dnd.DragSourceListener

Parameters:

dsde - the DragSourceDragEvent

dragEnter

public void dragEnter(java.awt.dnd.DropTargetDragEvent dtde)

Called when a drag operation has encountered the DropTarget.

Specified by:

dragEnter in interface java.awt.dnd.DropTargetListener

Parameters:

dtde - the DropTargetDragEvent

dragExit

public void dragExit(java.awt.dnd.DragSourceEvent dse)

Called as the hotspot exits a platform dependent drop site. This method is invoked when the following conditions are true:

• The cursor's logical hotspot no longer intersects the visible geometry of the Component associated with the previous dragEnter() invocation.

OR

• The Component that the logical cursor's hotspot intersected that resulted in the previous dragEnter() invocation no longer has an active DropTarget or DropTargetListener associated with it.

OR

• The current DropTarget's DropTargetListener has invoked rejectDrag() since the last dragEnter() or dragOver() invocation.

Specified by:

dragExit in interface java.awt.dnd.DragSourceListener

Parameters:

dse - the DragSourceEvent

dragExit

public void dragExit(java.awt.dnd.DropTargetEvent dte)

The drag operation has departed the DropTarget without dropping.

Specified by:

dragExit in interface java.awt.dnd.DropTargetListener

Parameters:

dte - the DropTargetEvent

dragOver

public void dragOver(java.awt.dnd.DragSourceDragEvent dsde)

Called as the hotspot moves over a platform dependent drop site. This method is invoked when the following conditions are true:

• The cursor's logical hotspot has moved but still intersects the visible geometry of the Component associated with the previous dragEnter() invocation.
• That Component still has a DropTarget associated with it.
• That DropTarget is still active.
• The DropTarget's registered DropTargetListener dragOver() method is invoked and returns successfully.
• The DropTarget does not reject the drag via rejectDrag()

Specified by:

dragOver in interface java.awt.dnd.DragSourceListener

Parameters:

dsde - the DragSourceDragEvent

dragOver

public void dragOver(java.awt.dnd.DropTargetDragEvent dtde)

Called when a drag operation is ongoing on the DropTarget.

Specified by:

dragOver in interface java.awt.dnd.DropTargetListener

Parameters:

dtde - the DropTargetDragEvent

drop

public void drop(java.awt.dnd.DropTargetDropEvent dtde)

The drag operation has terminated with a drop on this DropTarget. This method is responsible for undertaking the transfer of the data associated with the gesture. The DropTargetDropEvent provides a means to obtain a Transferable object that represents the data object(s) to be transfered.

From this method, the DropTargetListener shall accept or reject the drop via the acceptDrop(int dropAction) or rejectDrop() methods of the DropTargetDropEvent parameter.

Subsequent to acceptDrop(), but not before, DropTargetDropEvent's getTransferable() method may be invoked, and data transfer may be performed via the returned Transferable's getTransferData() method.

At the completion of a drop, an implementation of this method is required to signal the success/failure of the drop by passing an appropriate boolean to the DropTargetDropEvent's dropComplete(boolean success) method.

Note: The actual processing of the data transfer is not required to finish before this method returns. It may be deferred until later.

Specified by:

drop in interface java.awt.dnd.DropTargetListener

Parameters:

dtde - the DropTargetDropEvent

dropActionChanged

public void dropActionChanged(java.awt.dnd.DragSourceDragEvent dsde)

Called when the user has modified the drop gesture. This method is invoked when the state of the input device(s) that the user is interacting with changes. Such devices are typically the mouse buttons or keyboard modifiers that the user is interacting with.

Specified by:

dropActionChanged in interface java.awt.dnd.DragSourceListener

Parameters:

dsde - the DragSourceDragEvent

dropActionChanged

public void dropActionChanged(java.awt.dnd.DropTargetDragEvent dtde)

Called if the user has modified the current drop gesture.

Specified by:

dropActionChanged in interface java.awt.dnd.DropTargetListener

Parameters:

dtde - the DropTargetDragEvent

getCursor

public java.awt.Cursor getCursor(java.awt.Cursor default_cursor)

Get the Cursor object associated with the default_cursor. If not found, return the passed cursor.

getDefaultAction

public int getDefaultAction()

Returns the default DnD action.

Returns:

int

setCursor

public void setCursor(java.awt.Image img,
                      java.awt.Cursor default_cursor)

Sets a custom Cursor object associated with the default_cursor.

setDefaultAction

public void setDefaultAction(int newAction)

Sets the default DnD action.

Parameters:

newAction - int