/* * Copyright (c) 1998, 1999, Oracle and/or its affiliates. All rights reserved. * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. * * * * * * * * * * * * * * * * * * * * */ package java.awt.dnd; import java.awt.Insets; import java.awt.Point; /** * During DnD operations it is possible that a user may wish to drop the * subject of the operation on a region of a scrollable GUI control that is * not currently visible to the user. *
* In such situations it is desirable that the GUI control detect this * and institute a scroll operation in order to make obscured region(s) * visible to the user. This feature is known as autoscrolling. *
* If a GUI control is both an active DropTarget
* and is also scrollable, it
* can receive notifications of autoscrolling gestures by the user from
* the DnD system by implementing this interface.
*
* An autoscrolling gesture is initiated by the user by keeping the drag
* cursor motionless with a border region of the Component
,
* referred to as
* the "autoscrolling region", for a predefined period of time, this will
* result in repeated scroll requests to the Component
* until the drag Cursor
resumes its motion.
*
* @since 1.2
*/
public interface Autoscroll {
/**
* This method returns the Insets
describing
* the autoscrolling region or border relative
* to the geometry of the implementing Component.
*
* This value is read once by the DropTarget
* upon entry of the drag Cursor
* into the associated Component
.
*
* @return the Insets
*/
public Insets getAutoscrollInsets();
/**
* notify the Component
to autoscroll
*
* @param cursorLocn A Point
indicating the
* location of the cursor that triggered this operation.
*/
public void autoscroll(Point cursorLocn);
}