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main.cpp Example File
^{demos/spreadsheet/main.cpp}

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 #include <QtGui>

 static QString encode_pos(int row, int col) {
     return QString(col + 'A') + QString::number(row + 1);
 }

 static void decode_pos(const QString &pos, int *row, int *col)
 {
     if (pos.isEmpty()) {
         *col = -1;
         *row = -1;
     } else {
         *col = pos.at(0).toLatin1() - 'A';
         *row = pos.right(pos.size() - 1).toInt() - 1;
     }
 }

 class SpreadSheetDelegate : public QItemDelegate
 {
     Q_OBJECT
 public:
     SpreadSheetDelegate(QObject *parent = 0);
     QWidget *createEditor(QWidget *parent, const QStyleOptionViewItem &,
         const QModelIndex &index) const;
     void setEditorData(QWidget *editor, const QModelIndex &index) const;
     void setModelData(QWidget *editor, QAbstractItemModel *model,
         const QModelIndex &index) const;
 private slots:
     void commitAndCloseEditor();
 };

 SpreadSheetDelegate::SpreadSheetDelegate(QObject *parent)
     : QItemDelegate(parent) {}

 QWidget *SpreadSheetDelegate::createEditor(QWidget *parent, const QStyleOptionViewItem&,
     const QModelIndex &index) const
 {
     if(index.column() == 1){
         QDateTimeEdit *editor = new QDateTimeEdit(parent);
         editor->setDisplayFormat("dd/M/yyyy");
         editor->setCalendarPopup(true);
         return editor;
     }
     QLineEdit *editor = new QLineEdit(parent);
     //create a completer with the strings in the column as model.
     QStringList allStrings;
     for(int i = 1; i<index.model()->rowCount(); i++){
         QString strItem(index.model()->data(index.sibling(i, index.column()), Qt::EditRole).toString());
         if(!allStrings.contains(strItem))
             allStrings.append(strItem);
     }
     QCompleter *autoComplete = new QCompleter(allStrings);
     editor->setCompleter(autoComplete);
     connect(editor, SIGNAL(editingFinished()), this, SLOT(commitAndCloseEditor()));
     return editor;
 }

 void SpreadSheetDelegate::commitAndCloseEditor()
 {
     QLineEdit *editor = qobject_cast<QLineEdit *>(sender());
     emit commitData(editor);
     emit closeEditor(editor);
 }

 void SpreadSheetDelegate::setEditorData(QWidget *editor, const QModelIndex &index) const
 {
     QLineEdit *edit = qobject_cast<QLineEdit *>(editor);
     if (edit) {
         edit->setText(index.model()->data(index, Qt::EditRole).toString());
     }
     else {
         QDateTimeEdit *dateEditor = qobject_cast<QDateTimeEdit *>(editor);
         if (dateEditor) {
             dateEditor->setDate(QDate::fromString(index.model()->data(index, Qt::EditRole).toString(), "d/M/yyyy"));
         }
     }
 }

 void SpreadSheetDelegate::setModelData(QWidget *editor, QAbstractItemModel *model,
     const QModelIndex &index) const
 {
     QLineEdit *edit = qobject_cast<QLineEdit *>(editor);
     if (edit) {
         model->setData(index, edit->text());
     }
     else {
         QDateTimeEdit *dateEditor = qobject_cast<QDateTimeEdit *>(editor);
         if (dateEditor) {
             model->setData(index, dateEditor->date().toString("dd/M/yyyy"));
         }
     }
 }

 class SpreadSheetItem : public QTableWidgetItem
 {
 public:
     SpreadSheetItem();
     SpreadSheetItem(const QString &text);

     QTableWidgetItem *clone() const;

     QVariant data(int role) const;
     void setData(int role, const QVariant &value);
     QVariant display() const;

     inline QString formula() const
         { return QTableWidgetItem::data(Qt::DisplayRole).toString(); }

     static QVariant computeFormula(const QString &formula,
                                    const QTableWidget *widget,
                                    const QTableWidgetItem *self = 0);

 private:
     mutable bool isResolving;
 };

 SpreadSheetItem::SpreadSheetItem()
     : QTableWidgetItem(), isResolving(false) {}

 SpreadSheetItem::SpreadSheetItem(const QString &text)
     : QTableWidgetItem(text), isResolving(false) {}

 QTableWidgetItem *SpreadSheetItem::clone() const
 {
     SpreadSheetItem *item = new SpreadSheetItem();
     *item = *this;
     return item;
 }

 QVariant SpreadSheetItem::data(int role) const
 {
     if (role == Qt::EditRole || role == Qt::StatusTipRole)
         return formula();

     if (role == Qt::DisplayRole)
         return display();

     QString t = display().toString();
     bool isNumber = false;
     int number = t.toInt(&isNumber);

     if (role == Qt::TextColorRole) {
         if (!isNumber)
             return qVariantFromValue(QColor(Qt::black));
         else if (number < 0)
             return qVariantFromValue(QColor(Qt::red));
         return qVariantFromValue(QColor(Qt::blue));
     }

     if (role == Qt::TextAlignmentRole)
         if (!t.isEmpty() && (t.at(0).isNumber() || t.at(0) == '-'))
             return (int)(Qt::AlignRight | Qt::AlignVCenter);

     return QTableWidgetItem::data(role);
 }

 void SpreadSheetItem::setData(int role, const QVariant &value)
 {
     QTableWidgetItem::setData(role, value);
     if (tableWidget())
         tableWidget()->viewport()->update();
 }

 QVariant SpreadSheetItem::display() const
 {
     // avoid circular dependencies
     if (isResolving)
         return QVariant();
     isResolving = true;
     QVariant result = computeFormula(formula(), tableWidget(), this);
     isResolving = false;
     return result;
 }

 QVariant SpreadSheetItem::computeFormula(const QString &formula,
                                          const QTableWidget *widget,
                                          const QTableWidgetItem *self)
 {
     // check if the string is actually a formula or not
     QStringList list = formula.split(' ');
     if (list.isEmpty() || !widget)
         return formula; // its a normal string

     QString op = list.value(0).toLower();

     int firstRow = -1;
     int firstCol = -1;
     int secondRow = -1;
     int secondCol = -1;

     if (list.count() > 1)
         decode_pos(list.value(1), &firstRow, &firstCol);
     if (list.count() > 2)
         decode_pos(list.value(2), &secondRow, &secondCol);

     const QTableWidgetItem *start = widget->item(firstRow, firstCol);
     const QTableWidgetItem *end = widget->item(secondRow, secondCol);

     int firstVal = start ? start->text().toInt() : 0;
     int secondVal = end ? end->text().toInt() : 0;

     QVariant result;
     if (op == "sum") {
         int sum = 0;
         for (int r = firstRow; r <= secondRow; ++r) {
             for (int c = firstCol; c <= secondCol; ++c) {
                 const QTableWidgetItem *tableItem = widget->item(r, c);
                 if (tableItem && tableItem != self)
                     sum += tableItem->text().toInt();
             }
         }
         result = sum;
     } else if (op == "+") {
         result = (firstVal + secondVal);
     } else if (op == "-") {
         result = (firstVal - secondVal);
     } else if (op == "*") {
         result = (firstVal * secondVal);
     } else if (op == "/") {
         if (secondVal == 0)
             result = QString("nan");
         else
             result = (firstVal / secondVal);
     } else if (op == "=") {
         if (start)
         result = start->text();
     } else {
         result = formula;
     }

     return result;
 }

 #if !defined(QT_NO_DBUS) && defined(Q_OS_UNIX)
 #include <QtDBus/QtDBus>

 class SpreadSheetAdaptor : public QDBusAbstractAdaptor
 {
     Q_OBJECT
     Q_CLASSINFO("D-Bus Interface", "com.trolltech.DBus.SpreadSheetDemo")

 public:
     SpreadSheetAdaptor(QTableWidget *table) : QDBusAbstractAdaptor(table), table(table)
     { QDBusConnection::sessionBus().registerObject("/SpreadSheetDemo", table); }

 public slots:
     QString computeFormula(const QString &formula)
     { return SpreadSheetItem::computeFormula(formula, table).toString(); }
 private:
     QTableWidget *table;
 };
 #endif // QT_NO_DBUS

 class SpreadSheet : public QMainWindow
 {
     Q_OBJECT
 public:
     SpreadSheet(int rows, int cols, QWidget *parent = 0);

 public slots:
     void updateStatus(QTableWidgetItem *item);
     void updateColor(QTableWidgetItem *item);
     void updateLineEdit(QTableWidgetItem *item);
     void returnPressed();
     void selectColor();
     void selectFont();
     void clear();
     void showAbout();

     void actionSum();
     void actionSubtract();
     void actionAdd();
     void actionMultiply();
     void actionDivide();

 protected:
     void setupContextMenu();
     void setupContents();

     void setupMenuBar();
     void createActions();

     void actionMath_helper(const QString &title, const QString &op);
     bool runInputDialog(const QString &title,
                         const QString &c1Text,
                         const QString &c2Text,
                         const QString &opText,
                         const QString &outText,
                         QString *cell1, QString *cell2, QString *outCell);

 private:
     QToolBar *toolBar;
     QAction *colorAction;
     QAction *fontAction;
     QAction *firstSeparator;
     QAction *cell_sumAction;
     QAction *cell_addAction;
     QAction *cell_subAction;
     QAction *cell_mulAction;
     QAction *cell_divAction;
     QAction *secondSeparator;
     QAction *clearAction;
     QAction *aboutSpreadSheet;
     QAction *exitAction;

     QLabel *cellLabel;
     QTableWidget *table;
     QLineEdit *formulaInput;
 };

 SpreadSheet::SpreadSheet(int rows, int cols, QWidget *parent)
     : QMainWindow(parent)
 {
     addToolBar(toolBar = new QToolBar());
     formulaInput = new QLineEdit();

     cellLabel = new QLabel(toolBar);
     cellLabel->setMinimumSize(80, 0);

     toolBar->addWidget(cellLabel);
     toolBar->addWidget(formulaInput);

     table = new QTableWidget(rows, cols, this);
     for (int c = 0; c < cols; ++c) {
         QString character(QChar('A' + c));
         table->setHorizontalHeaderItem(c, new QTableWidgetItem(character));
     }
     table->setItemPrototype(table->item(rows - 1, cols - 1));
     table->setItemDelegate(new SpreadSheetDelegate());
 #if !defined(QT_NO_DBUS) && defined(Q_OS_UNIX)
     new SpreadSheetAdaptor(table);
 #endif
     createActions();

     updateColor(0);
     setupMenuBar();
     setupContextMenu();
     setupContents();
     setCentralWidget(table);

     statusBar();
     connect(table, SIGNAL(currentItemChanged(QTableWidgetItem*, QTableWidgetItem*)),
             this, SLOT(updateStatus(QTableWidgetItem*)));
     connect(table, SIGNAL(currentItemChanged(QTableWidgetItem*, QTableWidgetItem*)),
             this, SLOT(updateColor(QTableWidgetItem*)));
     connect(table, SIGNAL(currentItemChanged(QTableWidgetItem*, QTableWidgetItem*)),
             this, SLOT(updateLineEdit(QTableWidgetItem*)));
     connect(table, SIGNAL(itemChanged(QTableWidgetItem*)),
             this, SLOT(updateStatus(QTableWidgetItem*)));
     connect(formulaInput, SIGNAL(returnPressed()), this, SLOT(returnPressed()));
     connect(table, SIGNAL(itemChanged(QTableWidgetItem*)),
             this, SLOT(updateLineEdit(QTableWidgetItem*)));
     setWindowTitle(tr("Spreadsheet"));
 }

 void SpreadSheet::createActions()
 {
     cell_sumAction = new QAction(tr("Sum"), this);
     connect(cell_sumAction, SIGNAL(triggered()), this, SLOT(actionSum()));

     cell_addAction = new QAction(tr("&Add"), this);
     cell_addAction->setShortcut(Qt::CTRL | Qt::Key_Plus);
     connect(cell_addAction, SIGNAL(triggered()), this, SLOT(actionAdd()));

     cell_subAction = new QAction(tr("&Subtract"), this);
     cell_subAction->setShortcut(Qt::CTRL | Qt::Key_Minus);
     connect(cell_subAction, SIGNAL(triggered()), this, SLOT(actionSubtract()));

     cell_mulAction = new QAction(tr("&Multiply"), this);
     cell_mulAction->setShortcut(Qt::CTRL | Qt::Key_multiply);
     connect(cell_mulAction, SIGNAL(triggered()), this, SLOT(actionMultiply()));

     cell_divAction = new QAction(tr("&Divide"), this);
     cell_divAction->setShortcut(Qt::CTRL | Qt::Key_division);
     connect(cell_divAction, SIGNAL(triggered()), this, SLOT(actionDivide()));

     fontAction = new QAction(tr("Font..."), this);
     fontAction->setShortcut(Qt::CTRL|Qt::Key_F);
     connect(fontAction, SIGNAL(triggered()), this, SLOT(selectFont()));

     colorAction = new QAction(QPixmap(16, 16), tr("Background &Color..."), this);
     connect(colorAction, SIGNAL(triggered()), this, SLOT(selectColor()));

     clearAction = new QAction(tr("Clear"), this);
     clearAction->setShortcut(Qt::Key_Delete);
     connect(clearAction, SIGNAL(triggered()), this, SLOT(clear()));

     aboutSpreadSheet = new QAction(tr("About Spreadsheet"), this);
     connect(aboutSpreadSheet, SIGNAL(triggered()), this, SLOT(showAbout()));

     exitAction = new QAction(tr("E&xit"), this);
     connect(exitAction, SIGNAL(triggered()), qApp, SLOT(quit()));

     firstSeparator = new QAction(this);
     firstSeparator->setSeparator(true);

     secondSeparator = new QAction(this);
     secondSeparator->setSeparator(true);

 }

 void SpreadSheet::setupMenuBar()
 {
     QMenu *fileMenu = menuBar()->addMenu(tr("&File"));
     fileMenu->addAction(exitAction);

     QMenu *cellMenu = menuBar()->addMenu(tr("&Cell"));
     cellMenu->addAction(cell_addAction);
     cellMenu->addAction(cell_subAction);
     cellMenu->addAction(cell_mulAction);
     cellMenu->addAction(cell_divAction);
     cellMenu->addAction(cell_sumAction);
     cellMenu->addSeparator();
     cellMenu->addAction(colorAction);
     cellMenu->addAction(fontAction);

     menuBar()->addSeparator();

     QMenu *aboutMenu = menuBar()->addMenu(tr("&Help"));
     aboutMenu->addAction(aboutSpreadSheet);
 }

 void SpreadSheet::updateStatus(QTableWidgetItem *item)
 {
     if (item && item == table->currentItem()) {
         statusBar()->showMessage(item->data(Qt::StatusTipRole).toString(), 1000);
         cellLabel->setText("Cell: (" + encode_pos(table->row(item), table->column(item)) + ")");
     }
 }

 void SpreadSheet::updateColor(QTableWidgetItem *item)
 {
     QPixmap pix(16, 16);
     QColor col;
     if (item)
         col = item->backgroundColor();
     if (!col.isValid())
         col = palette().base().color();

     QPainter pt(&pix);
     pt.fillRect(0, 0, 16, 16, col);

     QColor lighter = col.light();
     pt.setPen(lighter);
     QPoint lightFrame[] = { QPoint(0, 15), QPoint(0, 0), QPoint(15, 0) };
     pt.drawPolyline(lightFrame, 3);

     pt.setPen(col.dark());
     QPoint darkFrame[] = { QPoint(1, 15), QPoint(15, 15), QPoint(15, 1) };
     pt.drawPolyline(darkFrame, 3);

     pt.end();

     colorAction->setIcon(pix);
 }

 void SpreadSheet::updateLineEdit(QTableWidgetItem *item)
 {
     if (item != table->currentItem())
         return;
     if (item)
         formulaInput->setText(item->data(Qt::EditRole).toString());
     else
         formulaInput->clear();
 }

 void SpreadSheet::returnPressed()
 {
     QString text = formulaInput->text();
     int row = table->currentRow();
     int col = table->currentColumn();
     QTableWidgetItem *item = table->item(row, col);
     if (!item)
         table->setItem(row, col, new SpreadSheetItem(text));
     else
         item->setData(Qt::EditRole, text);
     table->viewport()->update();
 }

 void SpreadSheet::selectColor()
 {
     QTableWidgetItem *item = table->currentItem();
     QColor col = item ? item->backgroundColor() : table->palette().base().color();
     col = QColorDialog::getColor(col, this);
     if (!col.isValid())
         return;

     QList<QTableWidgetItem*> selected = table->selectedItems();
     if (selected.count() == 0)
         return;

     foreach(QTableWidgetItem *i, selected)
         if (i) i->setBackgroundColor(col);

     updateColor(table->currentItem());
 }

 void SpreadSheet::selectFont()
 {
     QList<QTableWidgetItem*> selected = table->selectedItems();
     if (selected.count() == 0)
         return;
     bool ok = false;
     QFont fnt = QFontDialog::getFont(&ok, font(), this);
     if (!ok)
         return;
     foreach(QTableWidgetItem *i, selected)
         if (i) i->setFont(fnt);
 }

 bool SpreadSheet::runInputDialog(const QString &title,
                                  const QString &c1Text,
                                  const QString &c2Text,
                                  const QString &opText,
                                  const QString &outText,
                                  QString *cell1, QString *cell2, QString *outCell)
 {

     QStringList rows, cols;
     for (int c = 0; c < table->columnCount(); ++c)
         cols << QChar('A' + c);
     for (int r = 0; r < table->rowCount(); ++r)
         rows << QString::number(1 + r);

     QDialog addDialog(this);
     addDialog.setWindowTitle(title);

     QGroupBox group(title, &addDialog);
     group.setMinimumSize(250, 100);

     QLabel cell1Label(c1Text, &group);
     QComboBox cell1RowInput(&group);
     int c1Row, c1Col;
     decode_pos(*cell1, &c1Row, &c1Col);
     cell1RowInput.addItems(rows);
     cell1RowInput.setCurrentIndex(c1Row);
     QComboBox cell1ColInput(&group);
     cell1ColInput.addItems(cols);
     cell1ColInput.setCurrentIndex(c1Col);

     QLabel operatorLabel(opText, &group);
     operatorLabel.setAlignment(Qt::AlignHCenter);

     QLabel cell2Label(c2Text, &group);
     QComboBox cell2RowInput(&group);
     int c2Row, c2Col;
     decode_pos(*cell2, &c2Row, &c2Col);
     cell2RowInput.addItems(rows);
     cell2RowInput.setCurrentIndex(c2Row);
     QComboBox cell2ColInput(&group);
     cell2ColInput.addItems(cols);
     cell2ColInput.setCurrentIndex(c2Col);

     QLabel equalsLabel("=", &group);
     equalsLabel.setAlignment(Qt::AlignHCenter);

     QLabel outLabel(outText, &group);
     QComboBox outRowInput(&group);
     int outRow, outCol;
     decode_pos(*outCell, &outRow, &outCol);
     outRowInput.addItems(rows);
     outRowInput.setCurrentIndex(outRow);
     QComboBox outColInput(&group);
     outColInput.addItems(cols);
     outColInput.setCurrentIndex(outCol);

     QPushButton cancelButton(tr("Cancel"), &addDialog);
     connect(&cancelButton, SIGNAL(clicked()), &addDialog, SLOT(reject()));

     QPushButton okButton(tr("OK"), &addDialog);
     okButton.setDefault(true);
     connect(&okButton, SIGNAL(clicked()), &addDialog, SLOT(accept()));

     QHBoxLayout *buttonsLayout = new QHBoxLayout;
     buttonsLayout->addStretch(1);
     buttonsLayout->addWidget(&okButton);
     buttonsLayout->addSpacing(10);
     buttonsLayout->addWidget(&cancelButton);

     QVBoxLayout *dialogLayout = new QVBoxLayout(&addDialog);
     dialogLayout->addWidget(&group);
     dialogLayout->addStretch(1);
     dialogLayout->addItem(buttonsLayout);

     QHBoxLayout *cell1Layout = new QHBoxLayout;
     cell1Layout->addWidget(&cell1Label);
     cell1Layout->addSpacing(10);
     cell1Layout->addWidget(&cell1ColInput);
     cell1Layout->addSpacing(10);
     cell1Layout->addWidget(&cell1RowInput);

     QHBoxLayout *cell2Layout = new QHBoxLayout;
     cell2Layout->addWidget(&cell2Label);
     cell2Layout->addSpacing(10);
     cell2Layout->addWidget(&cell2ColInput);
     cell2Layout->addSpacing(10);
     cell2Layout->addWidget(&cell2RowInput);

     QHBoxLayout *outLayout = new QHBoxLayout;
     outLayout->addWidget(&outLabel);
     outLayout->addSpacing(10);
     outLayout->addWidget(&outColInput);
     outLayout->addSpacing(10);
     outLayout->addWidget(&outRowInput);

     QVBoxLayout *vLayout = new QVBoxLayout(&group);
     vLayout->addItem(cell1Layout);
     vLayout->addWidget(&operatorLabel);
     vLayout->addItem(cell2Layout);
     vLayout->addWidget(&equalsLabel);
     vLayout->addStretch(1);
     vLayout->addItem(outLayout);

     if (addDialog.exec()) {
         *cell1 = cell1ColInput.currentText() + cell1RowInput.currentText();
         *cell2 = cell2ColInput.currentText() + cell2RowInput.currentText();
         *outCell = outColInput.currentText() + outRowInput.currentText();
         return true;
     }

     return false;
 }

 void SpreadSheet::actionSum()
 {

     int row_first = 0;
     int row_last = 0;
     int row_cur = 0;

     int col_first = 0;
     int col_last = 0;
     int col_cur = 0;

     QList<QTableWidgetItem*> selected = table->selectedItems();
     if (!selected.isEmpty()) {
         QTableWidgetItem *first = selected.first();
         QTableWidgetItem *last = selected.last();
         row_first = table->row(first);
         row_last = table->row(last);
         col_first = table->column(first);
         col_last = table->column(last);
     }

     QTableWidgetItem *current = table->currentItem();
     if (current) {
         row_cur = table->row(current);
         col_cur = table->column(current);
     }

     QString cell1 = encode_pos(row_first, col_first);
     QString cell2 = encode_pos(row_last, col_last);
     QString out = encode_pos(row_cur, col_cur);

     if (runInputDialog(tr("Sum cells"), tr("First cell:"), tr("Last cell:"),
                        QString("%1").arg(QChar(0x03a3)), tr("Output to:"),
                        &cell1, &cell2, &out)) {
         int row, col;
         decode_pos(out, &row, &col);
         table->item(row, col)->setText("sum " + cell1 + " " + cell2);
     }
 }

 void SpreadSheet::actionMath_helper(const QString &title, const QString &op)
 {
     QString cell1 = "C1";
     QString cell2 = "C2";
     QString out = "C3";

     QTableWidgetItem *current = table->currentItem();
     if (current)
         out = encode_pos(table->currentRow(), table->currentColumn());

     if (runInputDialog(title, tr("Cell 1"), tr("Cell 2"), op, tr("Output to:"),
                        &cell1, &cell2, &out)) {
         int row, col;
         decode_pos(out, &row, &col);
         table->item(row, col)->setText(op + " " + cell1 + " " + cell2);
     }
 }

 void SpreadSheet::actionAdd()
 {
     actionMath_helper(tr("Addition"), "+");
 }

 void SpreadSheet::actionSubtract()
 {
     actionMath_helper(tr("Subtraction"), "-");
 }

 void SpreadSheet::actionMultiply()
 {
     actionMath_helper(tr("Multiplication"), "*");
 }

 void SpreadSheet::actionDivide()
 {
     actionMath_helper(tr("Division"), "/");
 }

 void SpreadSheet::clear()
 {
     foreach (QTableWidgetItem *i, table->selectedItems())
         i->setText("");
 }

 void SpreadSheet::setupContextMenu()
 {
     addAction(cell_addAction);
     addAction(cell_subAction);
     addAction(cell_mulAction);
     addAction(cell_divAction);
     addAction(cell_sumAction);
     addAction(firstSeparator);
     addAction(colorAction);
     addAction(fontAction);
     addAction(secondSeparator);
     addAction(clearAction);
     setContextMenuPolicy(Qt::ActionsContextMenu);
 }

 void SpreadSheet::setupContents()
 {
     QColor titleBackground(Qt::lightGray);
     QFont titleFont = table->font();
     titleFont.setBold(true);

     // column 0
     table->setItem(0, 0, new SpreadSheetItem("Item"));
     table->item(0, 0)->setBackgroundColor(titleBackground);
     table->item(0, 0)->setToolTip("This column shows the purchased item/service");
     table->item(0, 0)->setFont(titleFont);
     table->setItem(1, 0, new SpreadSheetItem("AirportBus"));
     table->setItem(2, 0, new SpreadSheetItem("Flight (Munich)"));
     table->setItem(3, 0, new SpreadSheetItem("Lunch"));
     table->setItem(4, 0, new SpreadSheetItem("Flight (LA)"));
     table->setItem(5, 0, new SpreadSheetItem("Taxi"));
     table->setItem(6, 0, new SpreadSheetItem("Dinner"));
     table->setItem(7, 0, new SpreadSheetItem("Hotel"));
     table->setItem(8, 0, new SpreadSheetItem("Flight (Oslo)"));
     table->setItem(9, 0, new SpreadSheetItem("Total:"));
     table->item(9, 0)->setFont(titleFont);
     table->item(9,0)->setBackgroundColor(Qt::lightGray);
     // column 1
     table->setItem(0, 1, new SpreadSheetItem("Date"));
     table->item(0, 1)->setBackgroundColor(titleBackground);
     table->item(0, 1)->setToolTip("This column shows the purchase date, double click to change");
     table->item(0, 1)->setFont(titleFont);
     table->setItem(1, 1, new SpreadSheetItem("15/6/2006"));
     table->setItem(2, 1, new SpreadSheetItem("15/6/2006"));
     table->setItem(3, 1, new SpreadSheetItem("15/6/2006"));
     table->setItem(4, 1, new SpreadSheetItem("21/5/2006"));
     table->setItem(5, 1, new SpreadSheetItem("16/6/2006"));
     table->setItem(6, 1, new SpreadSheetItem("16/6/2006"));
     table->setItem(7, 1, new SpreadSheetItem("16/6/2006"));
     table->setItem(8, 1, new SpreadSheetItem("18/6/2006"));
     table->setItem(9, 1, new SpreadSheetItem());
     table->item(9,1)->setBackgroundColor(Qt::lightGray);
     // column 2
     table->setItem(0, 2, new SpreadSheetItem("Price"));
     table->item(0, 2)->setBackgroundColor(titleBackground);
     table->item(0, 2)->setToolTip("This column shows the price of the purchase");
     table->item(0, 2)->setFont(titleFont);
     table->setItem(1, 2, new SpreadSheetItem("150"));
     table->setItem(2, 2, new SpreadSheetItem("2350"));
     table->setItem(3, 2, new SpreadSheetItem("-14"));
     table->setItem(4, 2, new SpreadSheetItem("980"));
     table->setItem(5, 2, new SpreadSheetItem("5"));
     table->setItem(6, 2, new SpreadSheetItem("120"));
     table->setItem(7, 2, new SpreadSheetItem("300"));
     table->setItem(8, 2, new SpreadSheetItem("1240"));
     table->setItem(9, 2, new SpreadSheetItem());
     table->item(9,2)->setBackgroundColor(Qt::lightGray);
     // column 3
     table->setItem(0, 3, new SpreadSheetItem("Currency"));
     table->item(0, 3)->setBackgroundColor(titleBackground);
     table->item(0, 3)->setToolTip("This column shows the currency");
     table->item(0, 3)->setFont(titleFont);
     table->setItem(1, 3, new SpreadSheetItem("NOK"));
     table->setItem(2, 3, new SpreadSheetItem("NOK"));
     table->setItem(3, 3, new SpreadSheetItem("EUR"));
     table->setItem(4, 3, new SpreadSheetItem("EUR"));
     table->setItem(5, 3, new SpreadSheetItem("USD"));
     table->setItem(6, 3, new SpreadSheetItem("USD"));
     table->setItem(7, 3, new SpreadSheetItem("USD"));
     table->setItem(8, 3, new SpreadSheetItem("USD"));
     table->setItem(9, 3, new SpreadSheetItem());
     table->item(9,3)->setBackgroundColor(Qt::lightGray);
     // column 4
     table->setItem(0, 4, new SpreadSheetItem("Ex.Rate"));
     table->item(0, 4)->setBackgroundColor(titleBackground);
     table->item(0, 4)->setToolTip("This column shows the exchange rate to NOK");
     table->item(0, 4)->setFont(titleFont);
     table->setItem(1, 4, new SpreadSheetItem("1"));
     table->setItem(2, 4, new SpreadSheetItem("1"));
     table->setItem(3, 4, new SpreadSheetItem("8"));
     table->setItem(4, 4, new SpreadSheetItem("8"));
     table->setItem(5, 4, new SpreadSheetItem("7"));
     table->setItem(6, 4, new SpreadSheetItem("7"));
     table->setItem(7, 4, new SpreadSheetItem("7"));
     table->setItem(8, 4, new SpreadSheetItem("7"));
     table->setItem(9, 4, new SpreadSheetItem());
     table->item(9,4)->setBackgroundColor(Qt::lightGray);
     // column 5
     table->setItem(0, 5, new SpreadSheetItem("NOK"));
     table->item(0, 5)->setBackgroundColor(titleBackground);
     table->item(0, 5)->setToolTip("This column shows the expenses in NOK");
     table->item(0, 5)->setFont(titleFont);
     table->setItem(1, 5, new SpreadSheetItem("* C2 E2"));
     table->setItem(2, 5, new SpreadSheetItem("* C3 E3"));
     table->setItem(3, 5, new SpreadSheetItem("* C4 E4"));
     table->setItem(4, 5, new SpreadSheetItem("* C5 E5"));
     table->setItem(5, 5, new SpreadSheetItem("* C6 E6"));
     table->setItem(6, 5, new SpreadSheetItem("* C7 E7"));
     table->setItem(7, 5, new SpreadSheetItem("* C8 E8"));
     table->setItem(8, 5, new SpreadSheetItem("* C9 E9"));
     table->setItem(9, 5, new SpreadSheetItem("sum F2 F9"));
     table->item(9,5)->setBackgroundColor(Qt::lightGray);

 }

 const char *htmlText =
 "<HTML>"
 "<p><b>This demo shows use of <c>QTableWidget</c> with custom handling for"
 " individual cells.</b></p>"
 "<p>Using a customized table item we make it possible to have dynamic"
 " output in different cells. The content that is implemented for this"
 " particular demo is:"
 "<ul>"
 "<li>Adding two cells.</li>"
 "<li>Subtracting one cell from another.</li>"
 "<li>Multiplying two cells.</li>"
 "<li>Dividing one cell with another.</li>"
 "<li>Summing the contents of an arbitrary number of cells.</li>"
 "</HTML>";

 void SpreadSheet::showAbout()
 {
     QMessageBox::about(this, "About Spreadsheet", htmlText);
 }

 int main(int argc, char** argv) {
     Q_INIT_RESOURCE(spreadsheet);
     QApplication app(argc, argv);
     SpreadSheet sheet(10, 6);
     sheet.setWindowIcon(QPixmap(":/images/interview.png"));
     sheet.resize(640, 420);
     sheet.show();
     return app.exec();
 }

 #include "main.moc"