highlighter.cpp Example File

richtext/syntaxhighlighter/highlighter.cpp
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#include "highlighter.h" Highlighter::Highlighter(QTextDocument *parent) : QSyntaxHighlighter(parent) { HighlightingRule rule; keywordFormat.setForeground(Qt::darkBlue); keywordFormat.setFontWeight(QFont::Bold); QStringList keywordPatterns; keywordPatterns << "\\bchar\\b" << "\\bclass\\b" << "\\bconst\\b" << "\\bdouble\\b" << "\\benum\\b" << "\\bexplicit\\b" << "\\bfriend\\b" << "\\binline\\b" << "\\bint\\b" << "\\blong\\b" << "\\bnamespace\\b" << "\\boperator\\b" << "\\bprivate\\b" << "\\bprotected\\b" << "\\bpublic\\b" << "\\bshort\\b" << "\\bsignals\\b" << "\\bsigned\\b" << "\\bslots\\b" << "\\bstatic\\b" << "\\bstruct\\b" << "\\btemplate\\b" << "\\btypedef\\b" << "\\btypename\\b" << "\\bunion\\b" << "\\bunsigned\\b" << "\\bvirtual\\b" << "\\bvoid\\b" << "\\bvolatile\\b" << "\\bbool\\b"; foreach (const QString &pattern, keywordPatterns) { rule.pattern = QRegularExpression(pattern); rule.format = keywordFormat; highlightingRules.append(rule); } classFormat.setFontWeight(QFont::Bold); classFormat.setForeground(Qt::darkMagenta); rule.pattern = QRegularExpression("\\bQ[A-Za-z]+\\b"); rule.format = classFormat; highlightingRules.append(rule); singleLineCommentFormat.setForeground(Qt::red); rule.pattern = QRegularExpression("//[^\n]*"); rule.format = singleLineCommentFormat; highlightingRules.append(rule); multiLineCommentFormat.setForeground(Qt::red); quotationFormat.setForeground(Qt::darkGreen); rule.pattern = QRegularExpression("\".*\""); rule.format = quotationFormat; highlightingRules.append(rule); functionFormat.setFontItalic(true); functionFormat.setForeground(Qt::blue); rule.pattern = QRegularExpression("\\b[A-Za-z0-9_]+(?=\\()"); rule.format = functionFormat; highlightingRules.append(rule); commentStartExpression = QRegularExpression("/\\*"); commentEndExpression = QRegularExpression("\\*/"); } void Highlighter::highlightBlock(const QString &text) { foreach (const HighlightingRule &rule, highlightingRules) { QRegularExpressionMatchIterator matchIterator = rule.pattern.globalMatch(text); while (matchIterator.hasNext()) { QRegularExpressionMatch match = matchIterator.next(); setFormat(match.capturedStart(), match.capturedLength(), rule.format); } } setCurrentBlockState(0); int startIndex = 0; if (previousBlockState() != 1) startIndex = text.indexOf(commentStartExpression); while (startIndex >= 0) { QRegularExpressionMatch match = commentEndExpression.match(text, startIndex); int endIndex = match.capturedStart(); int commentLength = 0; if (endIndex == -1) { setCurrentBlockState(1); commentLength = text.length() - startIndex; } else { commentLength = endIndex - startIndex + match.capturedLength(); } setFormat(startIndex, commentLength, multiLineCommentFormat); startIndex = text.indexOf(commentStartExpression, startIndex + commentLength); } }