spreadsheetitem.cpp Example File | Qt Widgets 5.12.8

- Qt 5.12
- Qt Widgets
- Spreadsheet
- spreadsheetitem.cpp Example File
- Qt 5.12.8 Reference Documentation

# spreadsheetitem.cpp Example File

itemviews/spreadsheet/spreadsheetitem.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2016 The Qt Company Ltd.
     ** Contact: https://www.qt.io/licensing/
     **
     ** This file is part of the demonstration applications of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** Commercial License Usage
     ** Licensees holding valid commercial Qt licenses may use this file in
     ** accordance with the commercial license agreement provided with the
     ** Software or, alternatively, in accordance with the terms contained in
     ** a written agreement between you and The Qt Company. For licensing terms
     ** and conditions see https://www.qt.io/terms-conditions. For further
     ** information use the contact form at https://www.qt.io/contact-us.
     **
     ** BSD License Usage
     ** Alternatively, you may use this file under the terms of the BSD license
     ** as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
     **   * Redistributions in binary form must reproduce the above copyright
     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
     **   * Neither the name of The Qt Company Ltd nor the names of its
     **     contributors may be used to endorse or promote products derived
     **     from this software without specific prior written permission.
     **
     **
     ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
     **
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #include "spreadsheetitem.h"

     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 QVariant::fromValue(QColor(Qt::black));
             else if (number < 0)
                 return QVariant::fromValue(QColor(Qt::red));
             return QVariant::fromValue(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; // it is 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;
     }