sortbuttonrenderer.java

该源代码为一些通用的程序

/* ========================================================================
 * JCommon : a free general purpose class library for the Java(tm) platform
 * ========================================================================
 *
 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
 * 
 * Project Info:  http://www.jfree.org/jcommon/index.html
 *
 * This library is free software; you can redistribute it and/or modify it 
 * under the terms of the GNU Lesser General Public License as published by 
 * the Free Software Foundation; either version 2.1 of the License, or 
 * (at your option) any later version.
 *
 * This library 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 Lesser General Public 
 * License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
 * USA.  
 *
 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
 * in the United States and other countries.]
 *
 * -----------------------
 * SortButtonRenderer.java
 * -----------------------
 * (C) Copyright 2000-2004, by Nobuo Tamemasa and Contributors.
 *
 * Original Author:  Nobuo Tamemasa;
 * Contributor(s):   David Gilbert (for Object Refinery Limited);
 *                   Gareth Davis;
 *
 * $Id: SortButtonRenderer.java,v 1.6 2005/11/16 15:58:41 taqua Exp $
 *
 * Changes (from 26-Oct-2001)
 * --------------------------
 * 26-Oct-2001 : Changed package to com.jrefinery.ui.* (DG);
 * 26-Jun-2002 : Removed unnecessary import (DG);
 * 14-Oct-2002 : Fixed errors reported by Checkstyle (DG);
 *
 */

package org.jfree.ui;

import java.awt.Component;
import java.awt.Insets;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JTable;
import javax.swing.SwingConstants;
import javax.swing.UIManager;
import javax.swing.border.Border;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;

/**
 * A table cell renderer for table headings - uses one of three JButton instances to indicate the
 * sort order for the table column.
 * <P>
 * This class (and also BevelArrowIcon) is adapted from original code by Nobuo Tamemasa (version
 * 1.0, 26-Feb-1999) posted on www.codeguru.com.
 *
 * @author David Gilbert
 */
public class SortButtonRenderer implements TableCellRenderer {

    /**
     * Useful constant indicating NO sorting.
     */
    public static final int NONE = 0;

    /**
     * Useful constant indicating ASCENDING (that is, arrow pointing down) sorting in the table.
     */
    public static final int DOWN = 1;

    /**
     * Useful constant indicating DESCENDING (that is, arrow pointing up) sorting in the table.
     */
    public static final int UP = 2;

    /**
     * The current pressed column (-1 for no column).
     */
    private int pressedColumn = -1;

    /**
     * The three buttons that are used to render the table header cells.
     */
    private JButton normalButton;

    /**
     * The three buttons that are used to render the table header cells.
     */
    private JButton ascendingButton;

    /**
     * The three buttons that are used to render the table header cells.
     */
    private JButton descendingButton;

    /**
     * Used to allow the class to work out whether to use the buttuns
     * or labels. Labels are required when using the aqua look and feel cos the
     * buttons won't fit.
     */
    private boolean useLabels;

    /**
     * The normal label (only used with MacOSX).
     */
    private JLabel normalLabel;

    /**
     * The ascending label (only used with MacOSX).
     */
    private JLabel ascendingLabel;

    /**
     * The descending label (only used with MacOSX).
     */
    private JLabel descendingLabel;

    /**
     * Creates a new button renderer.
     */
    public SortButtonRenderer() {

        this.pressedColumn = -1;
        this.useLabels = UIManager.getLookAndFeel().getID().equals("Aqua");

        final Border border = UIManager.getBorder("TableHeader.cellBorder");

        if (this.useLabels) {
            this.normalLabel = new JLabel();
            this.normalLabel.setHorizontalAlignment(SwingConstants.LEADING);

            this.ascendingLabel = new JLabel();
            this.ascendingLabel.setHorizontalAlignment(SwingConstants.LEADING);
            this.ascendingLabel.setHorizontalTextPosition(SwingConstants.LEFT);
            this.ascendingLabel.setIcon(new BevelArrowIcon(BevelArrowIcon.DOWN, false, false));

            this.descendingLabel = new JLabel();
            this.descendingLabel.setHorizontalAlignment(SwingConstants.LEADING);
            this.descendingLabel.setHorizontalTextPosition(SwingConstants.LEFT);
            this.descendingLabel.setIcon(new BevelArrowIcon(BevelArrowIcon.UP, false, false));

            this.normalLabel.setBorder(border);
            this.ascendingLabel.setBorder(border);
            this.descendingLabel.setBorder(border);
        }
        else {
            this.normalButton = new JButton();
            this.normalButton.setMargin(new Insets(0, 0, 0, 0));
            this.normalButton.setHorizontalAlignment(SwingConstants.LEADING);

            this.ascendingButton = new JButton();
            this.ascendingButton.setMargin(new Insets(0, 0, 0, 0));
            this.ascendingButton.setHorizontalAlignment(SwingConstants.LEADING);
            this.ascendingButton.setHorizontalTextPosition(SwingConstants.LEFT);
            this.ascendingButton.setIcon(new BevelArrowIcon(BevelArrowIcon.DOWN, false, false));
            this.ascendingButton.setPressedIcon(new BevelArrowIcon(BevelArrowIcon.DOWN, false, true));

            this.descendingButton = new JButton();
            this.descendingButton.setMargin(new Insets(0, 0, 0, 0));
            this.descendingButton.setHorizontalAlignment(SwingConstants.LEADING);
            this.descendingButton.setHorizontalTextPosition(SwingConstants.LEFT);
            this.descendingButton.setIcon(new BevelArrowIcon(BevelArrowIcon.UP, false, false));
            this.descendingButton.setPressedIcon(new BevelArrowIcon(BevelArrowIcon.UP, false, true));

            this.normalButton.setBorder(border);
            this.ascendingButton.setBorder(border);
            this.descendingButton.setBorder(border);

        }

    }

    /**
     * Returns the renderer component.
     *
     * @param table      the table.
     * @param value      the value.
     * @param isSelected selected?
     * @param hasFocus   focussed?
     * @param row        the row.
     * @param column     the column.
     * @return the renderer.
     */
    public Component getTableCellRendererComponent(final JTable table,
                                                   final Object value,
                                                   final boolean isSelected,
                                                   final boolean hasFocus,
                                                   final int row, final int column) {

        if (table == null) {
            throw new NullPointerException("Table must not be null.");
        }

        final JComponent component;
        final SortableTableModel model = (SortableTableModel) table.getModel();
        final int cc = table.convertColumnIndexToModel(column);
        final boolean isSorting = (model.getSortingColumn() == cc);
        final boolean isAscending = model.isAscending();

        final JTableHeader header = table.getTableHeader();
        final boolean isPressed = (cc == this.pressedColumn);

        if (this.useLabels) {
            final JLabel label = getRendererLabel(isSorting, isAscending);
            label.setText((value == null) ? "" : value.toString());
            component = label;
        }
        else {
            final JButton button = getRendererButton(isSorting, isAscending);
            button.setText((value == null) ? "" : value.toString());
            button.getModel().setPressed(isPressed);
            button.getModel().setArmed(isPressed);
            component = button;
        }

        if (header != null) {
            component.setForeground(header.getForeground());
            component.setBackground(header.getBackground());
            component.setFont(header.getFont());
        }
        return component;
    }

    /**
     * Returns the correct button component.
     *
     * @param isSorting whether the render component represents the sort column.
     * @param isAscending whether the model is ascending.
     * @return either the ascending, descending or normal button.
     */
    private JButton getRendererButton(final boolean isSorting, final boolean isAscending) {
        if (isSorting) {
            if (isAscending) {
                return ascendingButton;
            }
            else {
                return descendingButton;
            }
        }
        else {
            return normalButton;
        }
    }

    /**
     * Returns the correct label component.
     *
     * @param isSorting whether the render component represents the sort column.
     * @param isAscending whether the model is ascending.
     * @return either the ascending, descending or normal label.
     */
    private JLabel getRendererLabel(final boolean isSorting, final boolean isAscending) {
        if (isSorting) {
            if (isAscending) {
                return ascendingLabel;
            }
            else {
                return descendingLabel;
            }
        }
        else {
            return normalLabel;
        }
    }

    /**
     * Sets the pressed column.
     *
     * @param column the column.
     */
    public void setPressedColumn(final int column) {
        this.pressedColumn = column;
    }

}