source: trunk/src/qt3support/text/q3simplerichtext.cpp@ 352

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#include "q3simplerichtext.h"

#ifndef QT_NO_RICHTEXT
#include "q3richtext_p.h"
#include "qapplication.h"

QT_BEGIN_NAMESPACE

class Q3SimpleRichTextData
{
public:
    Q3TextDocument *doc;
    QFont font;
    int cachedWidth;
    bool cachedWidthWithPainter;
    void adjustSize();
};

// Pull this private function in from qglobal.cpp
Q_CORE_EXPORT unsigned int qt_int_sqrt(unsigned int n);

void Q3SimpleRichTextData::adjustSize() {
    QFontMetrics fm(font);
    int mw =  fm.width(QString(QLatin1Char('x'))) * 80;
    int w = mw;
    doc->doLayout(0,w);
    if (doc->widthUsed() != 0) {
        w = qt_int_sqrt(5 * doc->height() * doc->widthUsed() / 3);
        doc->doLayout(0, qMin(w, mw));

        if (w*3 < 5*doc->height()) {
            w = qt_int_sqrt(2 * doc->height() * doc->widthUsed());
            doc->doLayout(0,qMin(w, mw));
        }
    }
    cachedWidth = doc->width();
    cachedWidthWithPainter = false;
}

/*!
    \class Q3SimpleRichText
    \brief The Q3SimpleRichText class provides a small displayable piece of rich text.

    \compat

    This class encapsulates simple rich text usage in which a string
    is interpreted as rich text and can be drawn. This is particularly
    useful if you want to display some rich text in a custom widget. A
    Q3StyleSheet is needed to interpret the tags and format the rich
    text. Qt provides a default HTML-like style sheet, but you may
    define custom style sheets.

    Once created, the rich text object can be queried for its width(),
    height(), and the actual width used (see widthUsed()). Most
    importantly, it can be drawn on any given QPainter with draw().
    Q3SimpleRichText can also be used to implement hypertext or active
    text facilities by using anchorAt(). A hit test through inText()
    makes it possible to use simple rich text for text objects in
    editable drawing canvases.

    Once constructed from a string the contents cannot be changed,
    only resized. If the contents change, just throw the rich text
    object away and make a new one with the new contents.

    For large documents use QTextEdit or QTextBrowser. For very small
    items of rich text you can use a QLabel.

    If you are using Q3SimpleRichText to print in high resolution you
    should call setWidth(QPainter, int) so that the content will be
    laid out properly on the page.
*/

/*!
    Constructs a Q3SimpleRichText from the rich text string \a text and
    the font \a fnt.

    The font is used as a basis for the text rendering. When using
    rich text rendering on a widget \e w, you would normally specify
    the widget's font, for example:

    \snippet doc/src/snippets/code/src_qt3support_text_q3simplerichtext.cpp 0

    \a context is the optional context of the rich text object. This