QwtRichTextEngine Class Reference

A text engine for Qt rich texts. More...

#include <qwt_text_engine.h>

Inheritance diagram for QwtRichTextEngine:

Collaboration diagram for QwtRichTextEngine:

List of all members.

Public Member Functions
	QwtRichTextEngine ()
	Constructor.
virtual int	heightForWidth (const QFont &font, int flags, const QString &text, int width) const
virtual QSize	textSize (const QFont &font, int flags, const QString &text) const
virtual void	draw (QPainter *painter, const QRect &rect, int flags, const QString &text) const
virtual bool	mightRender (const QString &) const
virtual void	textMargins (const QFont &, const QString &, int &left, int &right, int &top, int &bottom) const

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Detailed Description

A text engine for Qt rich texts.

QwtRichTextEngine renders Qt rich texts using the classes of the Scribe framework of Qt.

Definition at line 150 of file qwt_text_engine.h.

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Constructor & Destructor Documentation

QwtRichTextEngine::QwtRichTextEngine

(

)

Constructor.

Definition at line 277 of file qwt_text_engine.cpp.

{
}

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Member Function Documentation

void QwtRichTextEngine::draw	(	QPainter *	painter,
		const QRect &	rect,
		int	flags,
		const QString &	text
	)		const [virtual]

Draw the text in a clipping rectangle

Parameters:

painter	Painter
rect	Clipping rectangle
flags	Bitwise OR of the flags like in for QPainter::drawText
text	Text to be rendered

Implements QwtTextEngine.

Definition at line 387 of file qwt_text_engine.cpp.

References QwtPainter::drawSimpleRichText().

{
    QwtRichTextDocument doc(text, flags, painter->font());
    QwtPainter::drawSimpleRichText(painter, rect, flags, doc);
}

int QwtRichTextEngine::heightForWidth	(	const QFont &	font,
		int	flags,
		const QString &	text,
		int	width
	)		const [virtual]

Find the height for a given width

Parameters:

font	Font of the text
flags	Bitwise OR of the flags used like in QPainter::drawText
text	Text to be rendered
width	Width

Returns:

Calculated height

Implements QwtTextEngine.

Definition at line 291 of file qwt_text_engine.cpp.

{
    QwtRichTextDocument doc(text, flags, font);

#if QT_VERSION < 0x040000
    doc.setWidth(width);
    const int h = doc.height();
#else
    doc.setPageSize(QSize(width, QWIDGETSIZE_MAX));
    const int h = qRound(doc.documentLayout()->documentSize().height());
#endif
    return h;
}

bool QwtRichTextEngine::mightRender

(

const QString &

text )

const [virtual]

Test if a string can be rendered by this text engine

Parameters:

text	Text to be tested

Returns:

QStyleSheet::mightBeRichText(text);

Implements QwtTextEngine.

Definition at line 413 of file qwt_text_engine.cpp.

{
#if QT_VERSION < 0x040000
    return QStyleSheet::mightBeRichText(text);
#else
    return Qt::mightBeRichText(text);
#endif
}

void QwtRichTextEngine::textMargins	(	const QFont &	,
		const QString &	,
		int &	left,
		int &	right,
		int &	top,
		int &	bottom
	)		const [virtual]

Return margins around the texts

Parameters:

left	Return 0
right	Return 0
top	Return 0
bottom	Return 0

Implements QwtTextEngine.

Definition at line 430 of file qwt_text_engine.cpp.

{
    left = right = top = bottom = 0;
}

QSize QwtRichTextEngine::textSize	(	const QFont &	font,
		int	flags,
		const QString &	text
	)		const [virtual]

Returns the size, that is needed to render text

Parameters:

font	Font of the text
flags	Bitwise OR of the flags used like in QPainter::drawText
text	Text to be rendered

Returns:

Caluclated size

Implements QwtTextEngine.

Definition at line 316 of file qwt_text_engine.cpp.

References qwtMax.

{
    QwtRichTextDocument doc(text, flags, font);

#if QT_VERSION < 0x040000
    doc.setWidth(QWIDGETSIZE_MAX);

    const int w = doc.widthUsed();
    const int h = doc.height();
    return QSize(w, h);

#else // QT_VERSION >= 0x040000

#if QT_VERSION < 0x040200
    /*
      Unfortunately offering the bounding rect calculation in the
      API of QTextDocument has been forgotten in Qt <= 4.1.x. It
      is planned to come with Qt 4.2.x.
      In the meantime we need a hack with a temporary QLabel,
      to reengineer the internal calculations.
    */

    static int off = 0;
    static QLabel *label = NULL;
    if ( label == NULL )
    {
        label = new QLabel;
        label->hide();

        const char *s = "XXXXX";
        label->setText(s);
        int w1 = label->sizeHint().width();
        const QFontMetrics fm(label->font());
        int w2 = fm.width(s);
        off = w1 - w2;
    }
    label->setFont(doc.defaultFont());
    label->setText(text);

    int w = qwtMax(label->sizeHint().width() - off, 0);
    doc.setPageSize(QSize(w, QWIDGETSIZE_MAX));

    int h = qRound(doc.documentLayout()->documentSize().height());
    return QSize(w, h);

#else // QT_VERSION >= 0x040200

#if QT_VERSION >= 0x040300
    QTextOption option = doc.defaultTextOption();
    if ( option.wrapMode() != QTextOption::NoWrap )
    {
        option.setWrapMode(QTextOption::NoWrap);
        doc.setDefaultTextOption(option);
        doc.adjustSize();
    }
#endif

    return doc.size().toSize();
#endif
#endif
}

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The documentation for this class was generated from the following files:

• qwt_text_engine.h
• qwt_text_engine.cpp