qt_demoe/third/3rd_qwt/qwt_plot_textlabel.h

76 lines
1.8 KiB
C++

/* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
* Qwt Widget Library
* Copyright (C) 1997 Josef Wilgen
* Copyright (C) 2002 Uwe Rathmann
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the Qwt License, Version 1.0
*****************************************************************************/
#ifndef QWT_PLOT_TEXT_LABEL_H
#define QWT_PLOT_TEXT_LABEL_H 1
#include "qwt_global.h"
#include "qwt_plot_item.h"
#include "qwt_text.h"
/*!
\brief A plot item, which displays a text label
QwtPlotTextLabel displays a text label aligned to the plot canvas.
In opposite to QwtPlotMarker the position of the label is unrelated to
plot coordinates.
As drawing a text is an expensive operation the label is cached
in a pixmap to speed up replots.
\par Example
The following code shows how to add a title.
\code
QwtText title( "Plot Title" );
title.setRenderFlags( Qt::AlignHCenter | Qt::AlignTop );
QFont font;
font.setBold( true );
title.setFont( font );
QwtPlotTextLabel *titleItem = new QwtPlotTextLabel();
titleItem->setText( title );
titleItem->attach( plot );
\endcode
\endpar
\sa QwtPlotMarker
*/
class QWT_EXPORT QwtPlotTextLabel: public QwtPlotItem
{
public:
QwtPlotTextLabel();
virtual ~QwtPlotTextLabel();
virtual int rtti() const;
void setText( const QwtText & );
QwtText text() const;
void setMargin( int margin );
int margin() const;
virtual QRectF textRect( const QRectF &, const QSizeF & ) const;
protected:
virtual void draw( QPainter *,
const QwtScaleMap &, const QwtScaleMap &,
const QRectF &) const;
void invalidateCache();
private:
class PrivateData;
PrivateData *d_data;
};
#endif