1 /*

     2  * Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies). 

     3  * All rights reserved.

     4  * This component and the accompanying materials are made available

     5  * under the terms of "Eclipse Public License v1.0"

     6  * which accompanies this distribution, and is available

     7  * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8  *

     9  * Initial Contributors:

    10  * Nokia Corporation - initial contribution.

    11  *

    12  * Contributors:

    13  *

    14  * Description:

    15  *

    16  * Table column sorter

    17  *

    18  */

    19 package com.nokia.trace.eventview;

    20 

    21 import org.eclipse.jface.viewers.TableViewer;

    22 import org.eclipse.jface.viewers.Viewer;

    23 import org.eclipse.jface.viewers.ViewerComparator;

    24 import org.eclipse.swt.SWT;

    25 import org.eclipse.swt.events.SelectionAdapter;

    26 import org.eclipse.swt.events.SelectionEvent;

    27 import org.eclipse.swt.widgets.TableColumn;

    28 

    29 /**

    30  * Table column sorter class

    31  * 

    32  */

    33 public abstract class TableColumnSorter extends ViewerComparator {

    34 

    35 	/**

    36 	 * Ascending sorting

    37 	 */

    38 	public static final int ASC = 1;

    39 

    40 	/**

    41 	 * No sorting

    42 	 */

    43 	public static final int NONE = 0;

    44 

    45 	/**

    46 	 * Descending sorting

    47 	 */

    48 	public static final int DESC = -1;

    49 

    50 	/**

    51 	 * Current direction

    52 	 */

    53 	private int direction = 0;

    54 

    55 	/**

    56 	 * Column for this sorter

    57 	 */

    58 	private TableColumn column;

    59 

    60 	/**

    61 	 * Table viewer for this column

    62 	 */

    63 	private TableViewer viewer;

    64 

    65 	/**

    66 	 * Constructor

    67 	 * 

    68 	 * @param viewer

    69 	 *            table viewer

    70 	 * @param column

    71 	 *            column

    72 	 */

    73 	public TableColumnSorter(final TableViewer viewer, TableColumn column) {

    74 		this.column = column;

    75 		this.viewer = viewer;

    76 		this.column.addSelectionListener(new SelectionAdapter() {

    77 

    78 			@Override

    79 			public void widgetSelected(SelectionEvent e) {

    80 				if (viewer.getComparator() != null) {

    81 					if (viewer.getComparator() == TableColumnSorter.this) {

    82 						int tdirection = TableColumnSorter.this.direction;

    83 

    84 						if (tdirection == ASC) {

    85 							setSorter(TableColumnSorter.this, DESC);

    86 						} else if (tdirection == DESC) {

    87 							setSorter(TableColumnSorter.this, NONE);

    88 						}

    89 					} else {

    90 						setSorter(TableColumnSorter.this, ASC);

    91 					}

    92 				} else {

    93 					setSorter(TableColumnSorter.this, ASC);

    94 				}

    95 			}

    96 		});

    97 	}

    98 

    99 	/**

   100 	 * Sets sorter

   101 	 * 

   102 	 * @param sorter

   103 	 *            the sorter

   104 	 * @param direction

   105 	 *            direction

   106 	 */

   107 	public void setSorter(TableColumnSorter sorter, int direction) {

   108 		if (direction == NONE) {

   109 			column.getParent().setSortColumn(null);

   110 			column.getParent().setSortDirection(SWT.NONE);

   111 			viewer.setComparator(null);

   112 		} else {

   113 			column.getParent().setSortColumn(column);

   114 			sorter.direction = direction;

   115 

   116 			if (direction == ASC) {

   117 				column.getParent().setSortDirection(SWT.DOWN);

   118 			} else {

   119 				column.getParent().setSortDirection(SWT.UP);

   120 			}

   121 

   122 			if (viewer.getComparator() == sorter) {

   123 				viewer.refresh();

   124 			} else {

   125 				viewer.setComparator(sorter);

   126 			}

   127 

   128 		}

   129 	}

   130 

   131 	/*

   132 	 * (non-Javadoc)

   133 	 * 

   134 	 * @see

   135 	 * org.eclipse.jface.viewers.ViewerComparator#compare(org.eclipse.jface.

   136 	 * viewers.Viewer, java.lang.Object, java.lang.Object)

   137 	 */

   138 	@Override

   139 	public int compare(Viewer viewer, Object o1, Object o2) {

   140 		return direction * doCompare(viewer, o1, o2);

   141 	}

   142 

   143 	/**

   144 	 * Compare method

   145 	 * 

   146 	 * @param TableViewer

   147 	 *            table viewer

   148 	 * @param o1

   149 	 *            object 1

   150 	 * @param o2

   151 	 *            object 2

   152 	 * @return less than 0 if o1 is smaller than o2, 0 if equal, more than 0 if

   153 	 *         o1 is bigger than o2

   154 	 */

   155 	protected abstract int doCompare(Viewer TableViewer, Object o1, Object o2);

   156 }