001/*
002 * Copyright (c) 2005 Einar Pehrson <einar@pehrson.nu>.
003 *
004 * This file is part of
005 * CleanSheets - a spreadsheet application for the Java platform.
006 *
007 * CleanSheets is free software; you can redistribute it and/or modify
008 * it under the terms of the GNU General Public License as published by
009 * the Free Software Foundation; either version 2 of the License, or
010 * (at your option) any later version.
011 *
012 * CleanSheets is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
015 * GNU General Public License for more details.
016 *
017 * You should have received a copy of the GNU General Public License
018 * along with CleanSheets; if not, write to the Free Software
019 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
020 */
021package csheets.ui.ext;
022
023import java.awt.Graphics;
024
025import javax.swing.JComponent;
026
027import csheets.core.Cell;
028
029/**
030 * A cell decorator visualizes extension-specific data by drawing on top of
031 * a cell's graphics context. Decorators should respect the enabled state set
032 * on them.
033 * @author Einar Pehrson
034 */
035public abstract class CellDecorator {
036
037        /** Whether the decorator should be used when rendering, default is false */
038        protected boolean enabled = false;
039
040        /**
041         * Creates a new cell decorator.
042         */
043        public CellDecorator() {}
044
045        /**
046         * Decorates the given graphics context, by drawing visualizations of
047         * extension-specific data on it.
048         * @param component the cell renderer component
049         * @param g the graphics context on which drawing should be done
050         * @param cell the cell being rendered
051         * @param selected whether the cell is selected
052         * @param hasFocus whether the cell has focus
053         */
054        public abstract void decorate(JComponent component, Graphics g, Cell cell,
055                        boolean selected, boolean hasFocus);
056
057        /**
058         * Returns whether the decorator should be used when rendering.
059         * @return true if the decorator should be used when rendering
060         */     
061        public final boolean isEnabled() {
062                return enabled;
063        }
064
065        /**
066         * Sets whether the decorator should be used when rendering.
067         * @param enabled whether the decorator should be used when rendering
068         */
069        public final void setEnabled(boolean enabled) {
070                this.enabled = enabled;
071        }
072}