ground/gcs/src/libs/qwt/src/qwt_abstract_legend.h

   1 /* -*- mode: C++ ; c-file-style: "stroustrup" -*- *****************************
   2  * Qwt Widget Library
   3  * Copyright (C) 1997   Josef Wilgen
   4  * Copyright (C) 2002   Uwe Rathmann
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the Qwt License, Version 1.0
   8  *****************************************************************************/
   9
  10 #ifndef QWT_ABSTRACT_LEGEND_H
  11 #define QWT_ABSTRACT_LEGEND_H
  12
  13 #include "qwt_global.h"
  14 #include "qwt_legend_data.h"
  15 #include <qframe.h>
  16 #include <qlist.h>
  17
  18 class QVariant;
  19
  20 /*!
  21   \brief Abstract base class for legend widgets
  22
  23   Legends, that need to be under control of the QwtPlot layout system
  24   need to be derived from QwtAbstractLegend.
  25
  26   \note Other type of legends can be implemented by connecting to
  27         the QwtPlot::legendDataChanged() signal. But as these legends
  28         are unknown to the plot layout system the layout code
  29         ( on screen and for QwtPlotRenderer ) need to be organized
  30         in application code.
  31
  32   \sa QwtLegend
  33  */
  34 class QWT_EXPORT QwtAbstractLegend : public QFrame
  35 {
  36     Q_OBJECT
  37
  38 public:
  39     explicit QwtAbstractLegend( QWidget *parent = NULL );
  40     virtual ~QwtAbstractLegend();
  41
  42     /*!
  43       Render the legend into a given rectangle.
  44
  45       \param painter Painter
  46       \param rect Bounding rectangle
  47       \param fillBackground When true, fill rect with the widget background
  48
  49       \sa renderLegend() is used by QwtPlotRenderer
  50     */
  51     virtual void renderLegend( QPainter *painter,
  52         const QRectF &rect, bool fillBackground ) const = 0;
  53
  54     //! \return True, when no plot item is inserted
  55     virtual bool isEmpty() const = 0;
  56
  57     virtual int scrollExtent( Qt::Orientation ) const;
  58
  59 public Q_SLOTS:
  60
  61     /*!
  62       \brief Update the entries for a plot item
  63
  64       \param itemInfo Info about an item
  65       \param data List of legend entry attributes for the  item
  66      */
  67     virtual void updateLegend( const QVariant &itemInfo,
  68         const QList<QwtLegendData> &data ) = 0;
  69 };
  70
  71 #endif