xmlsyntaxhighlighter.cpp Example File

  /****************************************************************************
  **
  ** Copyright (C) 2015 The Qt Company Ltd.
  ** Contact: http://www.qt.io/licensing/
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** You may use this file under the terms of the BSD license as follows:
  **
  ** "Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
  ** met:
  **   * Redistributions of source code must retain the above copyright
  **     notice, this list of conditions and the following disclaimer.
  **   * Redistributions in binary form must reproduce the above copyright
  **     notice, this list of conditions and the following disclaimer in
  **     the documentation and/or other materials provided with the
  **     distribution.
  **   * Neither the name of The Qt Company Ltd nor the names of its
  **     contributors may be used to endorse or promote products derived
  **     from this software without specific prior written permission.
  **
  **
  ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/

  #include "xmlsyntaxhighlighter.h"

  XmlSyntaxHighlighter::XmlSyntaxHighlighter(QTextDocument *parent)
      : QSyntaxHighlighter(parent)
  {
      HighlightingRule rule;

      // tag format
      tagFormat.setForeground(Qt::darkBlue);
      tagFormat.setFontWeight(QFont::Bold);
      rule.pattern = QRegExp("(<[a-zA-Z:]+\\b|<\\?[a-zA-Z:]+\\b|\\?>|>|/>|</[a-zA-Z:]+>)");
      rule.format = tagFormat;
      highlightingRules.append(rule);

      // attribute format
      attributeFormat.setForeground(Qt::darkGreen);
      rule.pattern = QRegExp("[a-zA-Z:]+=");
      rule.format = attributeFormat;
      highlightingRules.append(rule);

      // attribute content format
      attributeContentFormat.setForeground(Qt::red);
      rule.pattern = QRegExp("(\"[^\"]*\"|'[^']*')");
      rule.format = attributeContentFormat;
      highlightingRules.append(rule);

      commentFormat.setForeground(Qt::lightGray);
      commentFormat.setFontItalic(true);

      commentStartExpression = QRegExp("<!--");
      commentEndExpression = QRegExp("-->");
  }

  void XmlSyntaxHighlighter::highlightBlock(const QString &text)
  {
       foreach (const HighlightingRule &rule, highlightingRules) {
           QRegExp expression(rule.pattern);
           int index = text.indexOf(expression);
           while (index >= 0) {
               int length = expression.matchedLength();
               setFormat(index, length, rule.format);
               index = text.indexOf(expression, index + length);
           }
       }
       setCurrentBlockState(0);

       int startIndex = 0;
       if (previousBlockState() != 1)
           startIndex = text.indexOf(commentStartExpression);

       while (startIndex >= 0) {
           int endIndex = text.indexOf(commentEndExpression, startIndex);
           int commentLength;
           if (endIndex == -1) {
               setCurrentBlockState(1);
               commentLength = text.length() - startIndex;
           } else {
               commentLength = endIndex - startIndex
                               + commentEndExpression.matchedLength();
           }
           setFormat(startIndex, commentLength, commentFormat);
           startIndex = text.indexOf(commentStartExpression,
                                                   startIndex + commentLength);
       }
  }