001    /* ========================================================================
002     * JCommon : a free general purpose class library for the Java(tm) platform
003     * ========================================================================
004     *
005     * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006     * 
007     * Project Info:  http://www.jfree.org/jcommon/index.html
008     *
009     * This library is free software; you can redistribute it and/or modify it 
010     * under the terms of the GNU Lesser General Public License as published by 
011     * the Free Software Foundation; either version 2.1 of the License, or 
012     * (at your option) any later version.
013     *
014     * This library is distributed in the hope that it will be useful, but 
015     * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
016     * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public 
017     * License for more details.
018     *
019     * You should have received a copy of the GNU Lesser General Public
020     * License along with this library; if not, write to the Free Software
021     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
022     * USA.  
023     *
024     * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
025     * in the United States and other countries.]
026     * 
027     * --------------------------------
028     * SortableTableHeaderListener.java
029     * --------------------------------
030     * (C) Copyright 2000-2004, by Nabuo Tamemasa and Contributors.
031     *
032     * Original Author:  Nabuo Tamemasa;
033     * Contributor(s):   David Gilbert (for Object Refinery Limited);
034     *
035     * $Id: SortableTableHeaderListener.java,v 1.5 2007/11/02 17:50:36 taqua Exp $
036     *
037     * Changes (from 26-Oct-2001)
038     * --------------------------
039     * 26-Oct-2001 : Changed package to com.jrefinery.ui.*;
040     * 14-Oct-2002 : Fixed errors reported by Checkstyle (DG);
041     *
042     */
043    
044    package org.jfree.ui;
045    
046    import java.awt.event.MouseEvent;
047    import java.awt.event.MouseListener;
048    import java.awt.event.MouseMotionListener;
049    import javax.swing.table.JTableHeader;
050    
051    /**
052     * Captures mouse clicks on a table header, with the intention of triggering a sort.  Adapted from
053     * code by Nabuo Tamemasa posted on http://www.codeguru.com.
054     *
055     * @author Nabuo Tamemasa
056     */
057    public class SortableTableHeaderListener implements MouseListener, MouseMotionListener {
058    
059        /** A reference to the table model. */
060        private SortableTableModel model;
061    
062        /** The header renderer. */
063        private SortButtonRenderer renderer;
064    
065        /** The index of the column that is sorted - used to determine the state of the renderer. */
066        private int sortColumnIndex;
067    
068        /**
069         * Standard constructor.
070         *
071         * @param model  the model.
072         * @param renderer  the renderer.
073         */
074        public SortableTableHeaderListener(final SortableTableModel model, 
075                                           final SortButtonRenderer renderer) {
076            this.model = model;
077            this.renderer = renderer;
078        }
079    
080        /**
081         * Sets the table model for the listener.
082         *
083         * @param model  the model.
084         */
085        public void setTableModel(final SortableTableModel model) {
086            this.model = model;
087        }
088    
089        /**
090         * Handle a mouse press event - if the user is NOT resizing a column and NOT dragging a column
091         * then give visual feedback that the column header has been pressed.
092         *
093         * @param e  the mouse event.
094         */
095        public void mousePressed(final MouseEvent e) {
096    
097            final JTableHeader header = (JTableHeader) e.getComponent();
098    
099            if (header.getResizingColumn() == null) {  // resizing takes precedence over sorting
100                if (header.getDraggedDistance() < 1) {   // dragging also takes precedence over sorting
101                    final int columnIndex = header.columnAtPoint(e.getPoint());
102                    final int modelColumnIndex 
103                        = header.getTable().convertColumnIndexToModel(columnIndex);
104                    if (this.model.isSortable(modelColumnIndex)) {
105                        this.sortColumnIndex = header.getTable().convertColumnIndexToModel(columnIndex);
106                        this.renderer.setPressedColumn(this.sortColumnIndex);
107                        header.repaint();
108                        if (header.getTable().isEditing()) {
109                            header.getTable().getCellEditor().stopCellEditing();
110                        }
111                    }
112                    else {
113                        this.sortColumnIndex = -1;
114                    }
115                }
116            }
117    
118        }
119    
120        /**
121         * If the user is dragging or resizing, then we clear the sort column.
122         *
123         * @param e  the mouse event.
124         */
125        public void mouseDragged(final MouseEvent e) {
126    
127            final JTableHeader header = (JTableHeader) e.getComponent();
128    
129            if ((header.getDraggedDistance() > 0) || (header.getResizingColumn() != null)) {
130                this.renderer.setPressedColumn(-1);
131                this.sortColumnIndex = -1;
132            }
133        }
134    
135        /**
136         * This event is ignored (not required).
137         *
138         * @param e  the mouse event.
139         */
140        public void mouseEntered(final MouseEvent e) {
141            // not required
142        }
143    
144        /**
145         * This event is ignored (not required).
146         *
147         * @param e  the mouse event.
148         */
149        public void mouseClicked(final MouseEvent e) {
150            // not required
151        }
152    
153        /**
154         * This event is ignored (not required).
155         *
156         * @param e  the mouse event.
157         */
158        public void mouseMoved(final MouseEvent e) {
159            // not required
160        }
161    
162        /**
163         * This event is ignored (not required).
164         *
165         * @param e  the mouse event.
166         */
167        public void mouseExited(final MouseEvent e) {
168            // not required
169        }
170    
171        /**
172         * When the user releases the mouse button, we attempt to sort the table.
173         *
174         * @param e  the mouse event.
175         */
176        public void mouseReleased(final MouseEvent e) {
177    
178            final JTableHeader header = (JTableHeader) e.getComponent();
179    
180            if (header.getResizingColumn() == null) {  // resizing takes precedence over sorting
181                if (this.sortColumnIndex != -1) {
182                    final SortableTableModel model = (SortableTableModel) header.getTable().getModel();
183                    final boolean ascending = !model.isAscending();
184                    model.setAscending(ascending);
185                    model.sortByColumn(this.sortColumnIndex, ascending);
186    
187                    this.renderer.setPressedColumn(-1);       // clear
188                    header.repaint();
189                }
190            }
191        }
192    
193    }