src/history.cpp

   1 /**
   2  * Copyright (C) 2007 Benjamin C. Meyer
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  17  */
  18
  19 #include "history.h"
  20
  21 #include <qaction.h>
  22 #include <qstyle.h>
  23 #include <qdebug.h>
  24
  25 History::History(QObject *parent) : QObject(parent), goForwardAction(0), goBackAction(0), currentLocation(-1)
  26 {
  27 }
  28
  29 History::~History()
  30 {
  31 }
  32
  33 QAction *History::backAction(QObject *parent)
  34 {
  35     QAction *action = new QAction(tr("Back"), parent);
  36     action->setShortcuts(QKeySequence::Back);
  37     action->setIcon(QIcon(":/pics/arrow-left.png"));
  38     action->setEnabled(false);
  39     action->setToolTip(tr("Back"));
  40     return action;
  41 }
  42
  43 QAction *History::forwardAction(QObject *parent)
  44 {
  45     QAction *action = new QAction(tr("Forward"), parent);
  46     action->setShortcuts(QKeySequence::Forward);
  47     action->setIcon(QIcon(":/pics/arrow-right.png"));
  48     action->setEnabled(false);
  49     action->setToolTip(tr("Forward"));
  50     return action;
  51 }
  52
  53 void History::currentChanged(const QModelIndex &index)
  54 {
  55     if (currentLocation < 0 || history.value(currentLocation) != index) {
  56         while (currentLocation >= 0 && currentLocation + 1 < history.count()) {
  57             history.removeLast();
  58         }
  59         history.append(index);
  60         ++currentLocation;
  61     }
  62     if (goForwardAction)
  63         goForwardAction->setEnabled(history.size() - currentLocation > 1);
  64     if (goBackAction)
  65         goBackAction->setEnabled(currentLocation > 0);
  66 }
  67
  68 void History::goBack()
  69 {
  70     if (!history.isEmpty() && currentLocation > 0) {
  71         --currentLocation;
  72         QModelIndex previousIndex = history.at(currentLocation);
  73         emit goToIndex(previousIndex);
  74     }
  75 }
  76
  77 void History::goForward()
  78 {
  79     if (!history.isEmpty() && currentLocation < history.size()) {
  80         ++currentLocation;
  81         QModelIndex nextIndex = history.at(currentLocation);
  82         emit goToIndex(nextIndex);
  83     }
  84 }
  85