| /* |
| * Copyright (c) 1997, 2003, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package javax.swing; |
| |
| import java.awt.Dimension; |
| import java.awt.Rectangle; |
| |
| |
| /** |
| * An interface that provides information to a scrolling container |
| * like JScrollPane. A complex component that's likely to be used |
| * as a viewing a JScrollPane viewport (or other scrolling container) |
| * should implement this interface. |
| * |
| * @see JViewport |
| * @see JScrollPane |
| * @see JScrollBar |
| * @author Hans Muller |
| */ |
| public interface Scrollable |
| { |
| /** |
| * Returns the preferred size of the viewport for a view component. |
| * For example, the preferred size of a <code>JList</code> component |
| * is the size required to accommodate all of the cells in its list. |
| * However, the value of <code>preferredScrollableViewportSize</code> |
| * is the size required for <code>JList.getVisibleRowCount</code> rows. |
| * A component without any properties that would affect the viewport |
| * size should just return <code>getPreferredSize</code> here. |
| * |
| * @return the preferredSize of a <code>JViewport</code> whose view |
| * is this <code>Scrollable</code> |
| * @see JViewport#getPreferredSize |
| */ |
| Dimension getPreferredScrollableViewportSize(); |
| |
| |
| /** |
| * Components that display logical rows or columns should compute |
| * the scroll increment that will completely expose one new row |
| * or column, depending on the value of orientation. Ideally, |
| * components should handle a partially exposed row or column by |
| * returning the distance required to completely expose the item. |
| * <p> |
| * Scrolling containers, like JScrollPane, will use this method |
| * each time the user requests a unit scroll. |
| * |
| * @param visibleRect The view area visible within the viewport |
| * @param orientation Either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL. |
| * @param direction Less than zero to scroll up/left, greater than zero for down/right. |
| * @return The "unit" increment for scrolling in the specified direction. |
| * This value should always be positive. |
| * @see JScrollBar#setUnitIncrement |
| */ |
| int getScrollableUnitIncrement(Rectangle visibleRect, int orientation, int direction); |
| |
| |
| /** |
| * Components that display logical rows or columns should compute |
| * the scroll increment that will completely expose one block |
| * of rows or columns, depending on the value of orientation. |
| * <p> |
| * Scrolling containers, like JScrollPane, will use this method |
| * each time the user requests a block scroll. |
| * |
| * @param visibleRect The view area visible within the viewport |
| * @param orientation Either SwingConstants.VERTICAL or SwingConstants.HORIZONTAL. |
| * @param direction Less than zero to scroll up/left, greater than zero for down/right. |
| * @return The "block" increment for scrolling in the specified direction. |
| * This value should always be positive. |
| * @see JScrollBar#setBlockIncrement |
| */ |
| int getScrollableBlockIncrement(Rectangle visibleRect, int orientation, int direction); |
| |
| |
| /** |
| * Return true if a viewport should always force the width of this |
| * <code>Scrollable</code> to match the width of the viewport. |
| * For example a normal |
| * text view that supported line wrapping would return true here, since it |
| * would be undesirable for wrapped lines to disappear beyond the right |
| * edge of the viewport. Note that returning true for a Scrollable |
| * whose ancestor is a JScrollPane effectively disables horizontal |
| * scrolling. |
| * <p> |
| * Scrolling containers, like JViewport, will use this method each |
| * time they are validated. |
| * |
| * @return True if a viewport should force the Scrollables width to match its own. |
| */ |
| boolean getScrollableTracksViewportWidth(); |
| |
| /** |
| * Return true if a viewport should always force the height of this |
| * Scrollable to match the height of the viewport. For example a |
| * columnar text view that flowed text in left to right columns |
| * could effectively disable vertical scrolling by returning |
| * true here. |
| * <p> |
| * Scrolling containers, like JViewport, will use this method each |
| * time they are validated. |
| * |
| * @return True if a viewport should force the Scrollables height to match its own. |
| */ |
| boolean getScrollableTracksViewportHeight(); |
| } |