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/*
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* Copyright 1998-1999 Sun Microsystems, Inc. All Rights Reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Sun designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Sun in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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* CA 95054 USA or visit www.sun.com if you need additional information or
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* have any questions.
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*/
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package java.awt.dnd;
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import java.awt.Insets;
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import java.awt.Point;
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/**
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* During DnD operations it is possible that a user may wish to drop the
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* subject of the operation on a region of a scrollable GUI control that is
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* not currently visible to the user.
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* <p>
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* In such situations it is desirable that the GUI control detect this
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* and institute a scroll operation in order to make obscured region(s)
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* visible to the user. This feature is known as autoscrolling.
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* <p>
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* If a GUI control is both an active <code>DropTarget</code>
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* and is also scrollable, it
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* can receive notifications of autoscrolling gestures by the user from
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* the DnD system by implementing this interface.
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* <p>
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* An autoscrolling gesture is initiated by the user by keeping the drag
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* cursor motionless with a border region of the <code>Component</code>,
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* referred to as
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* the "autoscrolling region", for a predefined period of time, this will
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* result in repeated scroll requests to the <code>Component</code>
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* until the drag <code>Cursor</code> resumes its motion.
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*
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* @since 1.2
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*/
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public interface Autoscroll {
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/**
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* This method returns the <code>Insets</code> describing
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* the autoscrolling region or border relative
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* to the geometry of the implementing Component.
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* <P>
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* This value is read once by the <code>DropTarget</code>
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* upon entry of the drag <code>Cursor</code>
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* into the associated <code>Component</code>.
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* <P>
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* @return the Insets
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*/
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public Insets getAutoscrollInsets();
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/**
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* notify the <code>Component</code> to autoscroll
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* <P>
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* @param cursorLocn A <code>Point</code> indicating the
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* location of the cursor that triggered this operation.
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*/
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public void autoscroll(Point cursorLocn);
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}
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