Method selectionChanged

src/frontend/spreadsheet/SpreadsheetView.cpp:3680–3764

! called on selections changes. Propagates the selection/deselection of columns to the \c Spreadsheet object. */

  called on selections changes. Propagates the selection/deselection of columns to the \c Spreadsheet object.
*/
void SpreadsheetView::selectionChanged(const QItemSelection& /*selected*/, const QItemSelection& /*deselected*/) {
	if (m_suppressSelectionChangedEvent)
		return;

	PERFTRACE(QLatin1String(Q_FUNC_INFO));

	// reset the column that was previosly selected from the context menu, if any
	m_selectedColumnFromContextMenu = -1;

	// determine the columns that were fully selected or deselected in the spreadsheet to also select/deselect them in the project explorer
	const auto* selModel = m_tableView->selectionModel();
	int fullySelectedCount = 0; // the number of fully selected columns
	bool notFullySelected = false; // check if we have columns that are not fully selected (some cells selected only)
	for (int col = 0; col < m_spreadsheet->columnCount(); ++col) {
		const bool selected = selModel->isColumnSelected(col);
		m_spreadsheet->setColumnSelectedInView(col, selected);
		if (selected)
			++fullySelectedCount;
		else if (!notFullySelected) //
			notFullySelected = selModel->columnIntersectsSelection(col);
	}

	// determine the number of selected cells, columns, missing and masked values in the current selection and show this information in the status bar.
	// Note, calling selModel->selectedIndexes() is very expensive for a high number of rows/cells in the spreadsheet and when whole columns are being
	// selected by clicking on the spreadsheet header. To avoid calling this expensive functions, handle the case when only full columns were selected:
	if (fullySelectedCount > 0 && !notFullySelected && m_spreadsheet->rowCount() > 10000) {
		Q_EMIT m_spreadsheet->statusInfo(i18n("Selected 1: %1 rows, %2 columns", m_spreadsheet->rowCount(), fullySelectedCount));
		return;
	}

	const auto& indexes = selModel->selectedIndexes();
	if (indexes.empty() || indexes.count() == 1) {
		Q_EMIT m_spreadsheet->statusInfo(QString());
		return;
	}
	else if (indexes.count() > 10000) { // more than 10k selected cells, skip the expensive logic below to check for maskes values, etc.
		Q_EMIT m_spreadsheet->statusInfo(i18n("Selected: %1 cells", indexes.count()));
		return;
	}

	const auto& columns = m_spreadsheet->children<Column>();
	int maskedValuesCount = 0;
	int missingValuesCount = 0;
	for (const auto& index : indexes) {
		const int col = index.column();
		const int row = index.row();
		const auto& column = columns.at(col);
		if (!column->isValid(row))
			missingValuesCount++;
		if (column->isMasked(row))
			maskedValuesCount++;
	}

	const int selectedCellsCount = indexes.count();
	const QPair<int, int> selectedRowCol = qMakePair(selectedRowCount(false), selectedColumnCount(false));
	QString selectedRowsText = i18np("row", "rows", selectedRowCol.first);
	QString selectedColumnsText = i18np("column", "columns", selectedRowCol.second);
	QString selectedCellsText = i18n("cells");