Qt 5.11 | Qt Widgets | Spreadsheet | spreadsheetitem.cpp Example File

Qt 5.11.3 Reference Documentation

# spreadsheetitem.cpp Example File

itemviews/spreadsheet/spreadsheetitem.cpp

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      #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;
      }