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

Qt 5.11.3 Reference Documentation

# spreadsheet.cpp Example File

itemviews/spreadsheet/spreadsheet.cpp

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      #include <QtWidgets>
      #if defined(QT_PRINTSUPPORT_LIB)
      #include <QtPrintSupport/qtprintsupportglobal.h>
      #if QT_CONFIG(printdialog)
      #include <QPrinter>
      #include <QPrintDialog>
      #endif
      #if QT_CONFIG(printpreviewdialog)
      #include <QPrintPreviewDialog>
      #endif
      #endif

      #include "spreadsheet.h"
      #include "spreadsheetdelegate.h"
      #include "spreadsheetitem.h"
      #include "printview.h"

      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);
          table->setSizeAdjustPolicy(QTableWidget::AdjustToContents);
          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());

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

          statusBar();
          connect(table, &QTableWidget::currentItemChanged,
                  this, &SpreadSheet::updateStatus);
          connect(table, &QTableWidget::currentItemChanged,
                  this, &SpreadSheet::updateColor);
          connect(table, &QTableWidget::currentItemChanged,
                  this, &SpreadSheet::updateLineEdit);
          connect(table, &QTableWidget::itemChanged,
                  this, &SpreadSheet::updateStatus);
          connect(formulaInput, &QLineEdit::returnPressed, this, &SpreadSheet::returnPressed);
          connect(table, &QTableWidget::itemChanged,
                  this, &SpreadSheet::updateLineEdit);

          setWindowTitle(tr("Spreadsheet"));
      }

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

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

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

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

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

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

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

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

          aboutSpreadSheet = new QAction(tr("About Spreadsheet"), this);
          connect(aboutSpreadSheet, &QAction::triggered, this, &SpreadSheet::showAbout);

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

          printAction = new QAction(tr("&Print"), this);
          connect(printAction, &QAction::triggered, this, &SpreadSheet::print);

          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(printAction);
          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(tr("Cell: (%1)").arg(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, &QAbstractButton::clicked, &addDialog, &QDialog::reject);

          QPushButton okButton(tr("OK"), &addDialog);
          okButton.setDefault(true);
          connect(&okButton, &QAbstractButton::clicked, &addDialog, &QDialog::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;
              int col;
              decode_pos(out, &row, &col);
              table->item(row, col)->setText(tr("sum %1 %2").arg(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(tr("%1 %2 %3").arg(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);
      }

      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;
          }
      }

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

      void SpreadSheet::print()
      {
      #if QT_CONFIG(printpreviewdialog)
          QPrinter printer(QPrinter::ScreenResolution);
          QPrintPreviewDialog dlg(&printer);
          PrintView view;
          view.setModel(table->model());
          connect(&dlg, &QPrintPreviewDialog::paintRequested, &view, &PrintView::print);
          dlg.exec();
      #endif
      }