source: trunk/src/qt3support/text/q3syntaxhighlighter.cpp@ 890

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#include "q3syntaxhighlighter.h"
#include "q3syntaxhighlighter_p.h"

#ifndef QT_NO_SYNTAXHIGHLIGHTER
#include "q3textedit.h"
#include "qtimer.h"

QT_BEGIN_NAMESPACE

/*!
    \class Q3SyntaxHighlighter
    \brief The Q3SyntaxHighlighter class is a base class for
    implementing Q3TextEdit syntax highlighters.

    \compat

    A syntax highligher automatically highlights parts of the text in
    a Q3TextEdit. Syntax highlighters are often used when the user is
    entering text in a specific format (for example, source code) and
    help the user to read the text and identify syntax errors.

    To provide your own syntax highlighting for Q3TextEdit, you must
    subclass Q3SyntaxHighlighter and reimplement highlightParagraph().

    When you create an instance of your Q3SyntaxHighlighter subclass,
    pass it the Q3TextEdit that you want the syntax highlighting to be
    applied to. After this your highlightParagraph() function will be
    called automatically whenever necessary. Use your
    highlightParagraph() function to apply formatting (e.g. setting
    the font and color) to the text that is passed to it.
*/

/*!
    Constructs the Q3SyntaxHighlighter and installs it on \a textEdit.
    Ownership of the Q3SyntaxHighlighter is transferred to the \a
    textEdit
*/

Q3SyntaxHighlighter::Q3SyntaxHighlighter(Q3TextEdit *textEdit)
    : para(0), edit(textEdit), d(new Q3SyntaxHighlighterPrivate)
{
    textEdit->document()->setPreProcessor(new Q3SyntaxHighlighterInternal(this));
    textEdit->document()->invalidate();
    QTimer::singleShot(0, textEdit->viewport(), SLOT(update()));
}

/*!
    Destructor. Uninstalls this syntax highlighter from the textEdit()
*/

Q3SyntaxHighlighter::~Q3SyntaxHighlighter()
{
    delete d;
    textEdit()->document()->setPreProcessor(0);
}

/*!
    \fn int Q3SyntaxHighlighter::highlightParagraph(const QString &text, int endStateOfLastPara)

    This function is called when necessary by the rich text engine,
    i.e. on paragraphs which have changed.

    In your reimplementation you should parse the paragraph's \a text
    and call setFormat() as often as necessary to apply any font and
    color changes that you require. Your function must return a value