regularexpressiondialog.cpp Example File | Qt Widgets 5.12.10

- Qt 5.12
- Qt Widgets
- QRegularExpression Example
- regularexpressiondialog.cpp Example File
- Qt 5.12.10 Reference Documentation

# regularexpressiondialog.cpp Example File

tools/regularexpression/regularexpressiondialog.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2016 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
     ** Copyright (C) 2016 Samuel Gaist <samuel.gaist@edeltech.ch>
     ** Copyright (C) 2016 The Qt Company Ltd.
     ** Contact: https://www.qt.io/licensing/
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
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     **
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     ** as follows:
     **
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     ** modification, are permitted provided that the following conditions are
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     ****************************************************************************/

     #include "regularexpressiondialog.h"

     #include <QApplication>

     #include <QCheckBox>
     #include <QComboBox>
     #include <QLabel>
     #include <QLineEdit>
     #include <QMenu>
     #include <QSpinBox>
     #include <QPlainTextEdit>
     #include <QTreeWidget>

     #include <QAction>
     #include <QClipboard>
     #include <QContextMenuEvent>

     #include <QHBoxLayout>
     #include <QGridLayout>
     #include <QFormLayout>

     #include <QRegularExpression>
     #include <QRegularExpressionMatch>
     #include <QRegularExpressionMatchIterator>

     Q_DECLARE_METATYPE(QRegularExpression::MatchType)

     static QString rawStringLiteral(QString pattern)
     {
         pattern.prepend(QLatin1String("R\"RX("));
         pattern.append(QLatin1String(")RX\""));
         return pattern;
     }

     static QString patternToCode(QString pattern)
     {
         pattern.replace(QLatin1String("\\"), QLatin1String("\\\\"));
         pattern.replace(QLatin1String("\""), QLatin1String("\\\""));
         pattern.prepend(QLatin1Char('"'));
         pattern.append(QLatin1Char('"'));
         return pattern;
     }

     static QString codeToPattern(QString code)
     {
         for (int i = 0; i < code.size(); ++i) {
             if (code.at(i) == QLatin1Char('\\'))
                 code.remove(i, 1);
         }
         if (code.startsWith(QLatin1Char('"')) && code.endsWith(QLatin1Char('"'))) {
             code.chop(1);
             code.remove(0, 1);
         }
         return code;
     }

     class PatternLineEdit : public QLineEdit
     {
         Q_OBJECT
     public:
         explicit PatternLineEdit(QWidget *parent = nullptr);

     private slots:
         void copyToCode();
         void pasteFromCode();
         void escapeSelection();

     protected:
         void contextMenuEvent(QContextMenuEvent *event) override;

     private:
         QAction *escapeSelectionAction;
         QAction *copyToCodeAction;
         QAction *pasteFromCodeAction;
     };

     PatternLineEdit::PatternLineEdit(QWidget *parent) :
         QLineEdit(parent),
         escapeSelectionAction(new QAction(tr("Escape Selection"), this)),
         copyToCodeAction(new QAction(tr("Copy to Code"), this)),
         pasteFromCodeAction(new QAction(tr("Paste from Code"), this))
     {
         setClearButtonEnabled(true);
         connect(escapeSelectionAction, &QAction::triggered, this, &PatternLineEdit::escapeSelection);
         connect(copyToCodeAction, &QAction::triggered, this, &PatternLineEdit::copyToCode);
         connect(pasteFromCodeAction, &QAction::triggered, this, &PatternLineEdit::pasteFromCode);
     #if !QT_CONFIG(clipboard)
         copyToCodeAction->setEnabled(false);
         pasteFromCodeAction->setEnabled(false);
     #endif
     }

     void PatternLineEdit::escapeSelection()
     {
         const QString selection = selectedText();
         const QString escapedSelection = QRegularExpression::escape(selection);
         if (escapedSelection != selection) {
             QString t = text();
             t.replace(selectionStart(), selection.size(), escapedSelection);
             setText(t);
         }
     }

     void PatternLineEdit::copyToCode()
     {
     #if QT_CONFIG(clipboard)
         QGuiApplication::clipboard()->setText(patternToCode(text()));
     #endif
     }

     void PatternLineEdit::pasteFromCode()
     {
     #if QT_CONFIG(clipboard)
         setText(codeToPattern(QGuiApplication::clipboard()->text()));
     #endif
     }

     void PatternLineEdit::contextMenuEvent(QContextMenuEvent *event)
     {
         QMenu *menu = createStandardContextMenu();
         menu->setAttribute(Qt::WA_DeleteOnClose);
         menu->addSeparator();
         escapeSelectionAction->setEnabled(hasSelectedText());
         menu->addAction(escapeSelectionAction);
         menu->addSeparator();
         menu->addAction(copyToCodeAction);
         menu->addAction(pasteFromCodeAction);
         menu->popup(event->globalPos());
     }

     class DisplayLineEdit : public QLineEdit
     {
     public:
         explicit DisplayLineEdit(QWidget *parent = nullptr);
     };

     DisplayLineEdit::DisplayLineEdit(QWidget *parent) : QLineEdit(parent)
     {
         setReadOnly(true);
         QPalette disabledPalette = palette();
         disabledPalette.setBrush(QPalette::Base, disabledPalette.brush(QPalette::Disabled, QPalette::Base));
         setPalette(disabledPalette);

     #if QT_CONFIG(clipboard)
         QAction *copyAction = new QAction(this);
         copyAction->setText(RegularExpressionDialog::tr("Copy to clipboard"));
         copyAction->setIcon(QIcon(QStringLiteral(":/images/copy.png")));
         connect(copyAction, &QAction::triggered, this,
                 [this] () { QGuiApplication::clipboard()->setText(text()); });
         addAction(copyAction, QLineEdit::TrailingPosition);
     #endif
     }

     RegularExpressionDialog::RegularExpressionDialog(QWidget *parent)
         : QDialog(parent)
     {
         setupUi();
         setWindowTitle(tr("QRegularExpression Example"));

         connect(patternLineEdit, &QLineEdit::textChanged, this, &RegularExpressionDialog::refresh);
         connect(subjectTextEdit, &QPlainTextEdit::textChanged, this, &RegularExpressionDialog::refresh);

         connect(caseInsensitiveOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(dotMatchesEverythingOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(multilineOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(extendedPatternSyntaxOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(invertedGreedinessOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(dontCaptureOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(useUnicodePropertiesOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(optimizeOnFirstUsageOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(dontAutomaticallyOptimizeOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);

         connect(offsetSpinBox, QOverload<int>::of(&QSpinBox::valueChanged),
                 this, &RegularExpressionDialog::refresh);

         connect(matchTypeComboBox, QOverload<int>::of(&QComboBox::currentIndexChanged),
                 this, &RegularExpressionDialog::refresh);

         connect(anchoredMatchOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
         connect(dontCheckSubjectStringMatchOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);

         patternLineEdit->setText(tr("(\\+?\\d+)-(?<prefix>\\d+)-(?<number>\\w+)"));
         subjectTextEdit->setPlainText(tr("My office number is +43-152-0123456, my mobile is 001-41-255512 instead."));

         refresh();
     }

     void RegularExpressionDialog::setResultUiEnabled(bool enabled)
     {
         matchDetailsTreeWidget->setEnabled(enabled);
         namedGroupsTreeWidget->setEnabled(enabled);
     }

     static void setTextColor(QWidget *widget, const QColor &color)
     {
         QPalette palette = widget->palette();
         palette.setColor(QPalette::Text, color);
         widget->setPalette(palette);
     }

     void RegularExpressionDialog::refresh()
     {
         setUpdatesEnabled(false);

         const QString pattern = patternLineEdit->text();
         const QString text = subjectTextEdit->toPlainText();

         offsetSpinBox->setMaximum(qMax(0, text.length() - 1));

         escapedPatternLineEdit->setText(patternToCode(pattern));
         rawStringLiteralLineEdit->setText(rawStringLiteral(pattern));

         setTextColor(patternLineEdit, subjectTextEdit->palette().color(QPalette::Text));
         matchDetailsTreeWidget->clear();
         namedGroupsTreeWidget->clear();
         regexpStatusLabel->setText(QString());

         if (pattern.isEmpty()) {
             setResultUiEnabled(false);
             setUpdatesEnabled(true);
             return;
         }

         QRegularExpression rx(pattern);
         if (!rx.isValid()) {
             setTextColor(patternLineEdit, Qt::red);
             regexpStatusLabel->setText(tr("Invalid: syntax error at position %1 (%2)")
                                        .arg(rx.patternErrorOffset())
                                        .arg(rx.errorString()));
             setResultUiEnabled(false);
             setUpdatesEnabled(true);
             return;
         }

         setResultUiEnabled(true);

         QRegularExpression::MatchType matchType = matchTypeComboBox->currentData().value<QRegularExpression::MatchType>();
         QRegularExpression::PatternOptions patternOptions = QRegularExpression::NoPatternOption;
         QRegularExpression::MatchOptions matchOptions = QRegularExpression::NoMatchOption;

         if (anchoredMatchOptionCheckBox->isChecked())
             matchOptions |= QRegularExpression::AnchoredMatchOption;
         if (dontCheckSubjectStringMatchOptionCheckBox->isChecked())
             matchOptions |= QRegularExpression::DontCheckSubjectStringMatchOption;

         if (caseInsensitiveOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::CaseInsensitiveOption;
         if (dotMatchesEverythingOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::DotMatchesEverythingOption;
         if (multilineOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::MultilineOption;
         if (extendedPatternSyntaxOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::ExtendedPatternSyntaxOption;
         if (invertedGreedinessOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::InvertedGreedinessOption;
         if (dontCaptureOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::DontCaptureOption;
         if (useUnicodePropertiesOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::UseUnicodePropertiesOption;
         if (optimizeOnFirstUsageOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::OptimizeOnFirstUsageOption;
         if (dontAutomaticallyOptimizeOptionCheckBox->isChecked())
             patternOptions |= QRegularExpression::DontAutomaticallyOptimizeOption;

         rx.setPatternOptions(patternOptions);

         const int capturingGroupsCount = rx.captureCount() + 1;

         QRegularExpressionMatchIterator iterator = rx.globalMatch(text, offsetSpinBox->value(), matchType, matchOptions);
         int i = 0;

         while (iterator.hasNext()) {
             QRegularExpressionMatch match = iterator.next();

             QTreeWidgetItem *matchDetailTopItem = new QTreeWidgetItem(matchDetailsTreeWidget);
             matchDetailTopItem->setText(0, QString::number(i));

             for (int captureGroupIndex = 0; captureGroupIndex < capturingGroupsCount; ++captureGroupIndex) {
                 QTreeWidgetItem *matchDetailItem = new QTreeWidgetItem(matchDetailTopItem);
                 matchDetailItem->setText(1, QString::number(captureGroupIndex));
                 matchDetailItem->setText(2, match.captured(captureGroupIndex));
             }

             ++i;
         }

         matchDetailsTreeWidget->expandAll();

         regexpStatusLabel->setText(tr("Valid"));

         const QStringList namedCaptureGroups = rx.namedCaptureGroups();
         for (int i = 0; i < namedCaptureGroups.size(); ++i) {
             const QString currentNamedCaptureGroup = namedCaptureGroups.at(i);

             QTreeWidgetItem *namedGroupItem = new QTreeWidgetItem(namedGroupsTreeWidget);
             namedGroupItem->setText(0, QString::number(i));
             namedGroupItem->setText(1, currentNamedCaptureGroup.isNull() ? tr("<no name>") : currentNamedCaptureGroup);
         }

         setUpdatesEnabled(true);
     }

     void RegularExpressionDialog::setupUi()
     {
         QWidget *leftHalfContainer = setupLeftUi();

         QFrame *verticalSeparator = new QFrame;
         verticalSeparator->setFrameStyle(QFrame::VLine | QFrame::Sunken);

         QWidget *rightHalfContainer = setupRightUi();

         QHBoxLayout *mainLayout = new QHBoxLayout;
         mainLayout->addWidget(leftHalfContainer);
         mainLayout->addWidget(verticalSeparator);
         mainLayout->addWidget(rightHalfContainer);

         setLayout(mainLayout);
     }

     QWidget *RegularExpressionDialog::setupLeftUi()
     {
         QWidget *container = new QWidget;

         QFormLayout *layout = new QFormLayout(container);
         layout->setFieldGrowthPolicy(QFormLayout::AllNonFixedFieldsGrow);
         layout->setMargin(0);

         QLabel *regexpAndSubjectLabel = new QLabel(tr("<h3>Regular expression and text input</h3>"));
         layout->addRow(regexpAndSubjectLabel);

         patternLineEdit = new PatternLineEdit;
         patternLineEdit->setClearButtonEnabled(true);
         layout->addRow(tr("&Pattern:"), patternLineEdit);

         rawStringLiteralLineEdit = new DisplayLineEdit;
         layout->addRow(tr("&Raw string literal:"), rawStringLiteralLineEdit);
         escapedPatternLineEdit = new DisplayLineEdit;
         layout->addRow(tr("&Escaped pattern:"), escapedPatternLineEdit);

         subjectTextEdit = new QPlainTextEdit;
         layout->addRow(tr("&Subject text:"), subjectTextEdit);

         caseInsensitiveOptionCheckBox = new QCheckBox(tr("Case insensitive (/i)"));
         dotMatchesEverythingOptionCheckBox = new QCheckBox(tr("Dot matches everything (/s)"));
         multilineOptionCheckBox = new QCheckBox(tr("Multiline (/m)"));
         extendedPatternSyntaxOptionCheckBox = new QCheckBox(tr("Extended pattern (/x)"));
         invertedGreedinessOptionCheckBox = new QCheckBox(tr("Inverted greediness"));
         dontCaptureOptionCheckBox = new QCheckBox(tr("Don't capture"));
         useUnicodePropertiesOptionCheckBox = new QCheckBox(tr("Use unicode properties (/u)"));
         optimizeOnFirstUsageOptionCheckBox = new QCheckBox(tr("Optimize on first usage"));
         dontAutomaticallyOptimizeOptionCheckBox = new QCheckBox(tr("Don't automatically optimize"));

         QGridLayout *patternOptionsCheckBoxLayout = new QGridLayout;
         int gridRow = 0;
         patternOptionsCheckBoxLayout->addWidget(caseInsensitiveOptionCheckBox, gridRow, 1);
         patternOptionsCheckBoxLayout->addWidget(dotMatchesEverythingOptionCheckBox, gridRow, 2);
         ++gridRow;
         patternOptionsCheckBoxLayout->addWidget(multilineOptionCheckBox, gridRow, 1);
         patternOptionsCheckBoxLayout->addWidget(extendedPatternSyntaxOptionCheckBox, gridRow, 2);
         ++gridRow;
         patternOptionsCheckBoxLayout->addWidget(invertedGreedinessOptionCheckBox, gridRow, 1);
         patternOptionsCheckBoxLayout->addWidget(dontCaptureOptionCheckBox, gridRow, 2);
         ++gridRow;
         patternOptionsCheckBoxLayout->addWidget(useUnicodePropertiesOptionCheckBox, gridRow, 1);
         patternOptionsCheckBoxLayout->addWidget(optimizeOnFirstUsageOptionCheckBox, gridRow, 2);
         ++gridRow;
         patternOptionsCheckBoxLayout->addWidget(dontAutomaticallyOptimizeOptionCheckBox, gridRow, 1);

         layout->addRow(tr("Pattern options:"), patternOptionsCheckBoxLayout);

         offsetSpinBox = new QSpinBox;
         layout->addRow(tr("Match &offset:"), offsetSpinBox);

         matchTypeComboBox = new QComboBox;
         matchTypeComboBox->addItem(tr("Normal"), QVariant::fromValue(QRegularExpression::NormalMatch));
         matchTypeComboBox->addItem(tr("Partial prefer complete"), QVariant::fromValue(QRegularExpression::PartialPreferCompleteMatch));
         matchTypeComboBox->addItem(tr("Partial prefer first"), QVariant::fromValue(QRegularExpression::PartialPreferFirstMatch));
         matchTypeComboBox->addItem(tr("No match"), QVariant::fromValue(QRegularExpression::NoMatch));
         layout->addRow(tr("Match &type:"), matchTypeComboBox);

         dontCheckSubjectStringMatchOptionCheckBox = new QCheckBox(tr("Don't check subject string"));
         anchoredMatchOptionCheckBox = new QCheckBox(tr("Anchored match"));

         QGridLayout *matchOptionsCheckBoxLayout = new QGridLayout;
         matchOptionsCheckBoxLayout->addWidget(dontCheckSubjectStringMatchOptionCheckBox, 0, 0);
         matchOptionsCheckBoxLayout->addWidget(anchoredMatchOptionCheckBox, 0, 1);
         layout->addRow(tr("Match options:"), matchOptionsCheckBoxLayout);

         return container;
     }

     QWidget *RegularExpressionDialog::setupRightUi()
     {
         QWidget *container = new QWidget;

         QFormLayout *layout = new QFormLayout(container);
         layout->setFieldGrowthPolicy(QFormLayout::AllNonFixedFieldsGrow);
         layout->setMargin(0);

         QLabel *matchInfoLabel = new QLabel(tr("<h3>Match information</h3>"));
         layout->addRow(matchInfoLabel);

         matchDetailsTreeWidget = new QTreeWidget;
         matchDetailsTreeWidget->setHeaderLabels(QStringList() << tr("Match index") << tr("Group index") << tr("Captured string"));
         matchDetailsTreeWidget->setSizeAdjustPolicy(QTreeWidget::AdjustToContents);
         layout->addRow(tr("Match details:"), matchDetailsTreeWidget);

         QFrame *horizontalSeparator = new QFrame;
         horizontalSeparator->setFrameStyle(QFrame::HLine | QFrame::Sunken);
         layout->addRow(horizontalSeparator);

         QLabel *regexpInfoLabel = new QLabel(tr("<h3>Regular expression information</h3>"));
         layout->addRow(regexpInfoLabel);

         regexpStatusLabel = new QLabel(tr("Valid"));
         regexpStatusLabel->setWordWrap(true);
         layout->addRow(tr("Pattern status:"), regexpStatusLabel);

         namedGroupsTreeWidget = new QTreeWidget;
         namedGroupsTreeWidget->setHeaderLabels(QStringList() << tr("Index") << tr("Named group"));
         namedGroupsTreeWidget->setSizeAdjustPolicy(QTreeWidget::AdjustToContents);
         namedGroupsTreeWidget->setRootIsDecorated(false);
         layout->addRow(tr("Named groups:"), namedGroupsTreeWidget);

         return container;
     }

     #include "regularexpressiondialog.moc"