QwtAbstractLegend(3)           Qwt User's Guide           QwtAbstractLegend(3)

NAME
       QwtAbstractLegend - Abstract base class for legend widgets.


SYNOPSIS
       #include <qwt_abstract_legend.h>

       Inherits QFrame.

       Inherited by QwtLegend.

   Public Slots
       virtual void updateLegend (const QVariant &itemInfo, const QList<
           QwtLegendData > &data)=0
           Update the entries for a plot item.

   Public Member Functions
       QwtAbstractLegend (QWidget *parent=NULL)
       virtual ~QwtAbstractLegend ()
           Destructor.
       virtual void renderLegend (QPainter *painter, const QRectF &rect, bool
           fillBackground) const =0
       virtual bool isEmpty () const =0
       virtual int scrollExtent (Qt::Orientation) const

Detailed Description
       Abstract base class for legend widgets.

       Legends, that need to be under control of the QwtPlot layout system
       need to be derived from QwtAbstractLegend.

       Note
           Other type of legends can be implemented by connecting to the
           QwtPlot::legendDataChanged() signal. But as these legends are
           unknown to the plot layout system the layout code ( on screen and
           for QwtPlotRenderer ) need to be organized in application code.

       See also
           QwtLegend

       Definition at line 34 of file qwt_abstract_legend.h.

Constructor & Destructor Documentation
   QwtAbstractLegend::QwtAbstractLegend (QWidget * parent = NULL) [explicit]
       Constructor

       Parameters
           parent Parent widget

       Definition at line 18 of file qwt_abstract_legend.cpp.

Member Function Documentation
   virtual bool QwtAbstractLegend::isEmpty () const [pure virtual]
       Returns
           True, when no plot item is inserted

       Implemented in QwtLegend.

   virtual void QwtAbstractLegend::renderLegend (QPainter * painter, const
       QRectF & rect, bool fillBackground) const [pure virtual]
       Render the legend into a given rectangle.

       Parameters
           painter Painter
           rect Bounding rectangle
           fillBackground When true, fill rect with the widget background

       See also
           renderLegend() is used by QwtPlotRenderer

       Implemented in QwtLegend.

   int QwtAbstractLegend::scrollExtent (Qt::Orientation orientation) const
       [virtual]
       Return the extent, that is needed for elements to scroll the legend (
       usually scrollbars ),

       Parameters
           orientation Orientation

       Returns
           Extent of the corresponding scroll element

       Reimplemented in QwtLegend.

       Definition at line 35 of file qwt_abstract_legend.cpp.

   virtual void QwtAbstractLegend::updateLegend (const QVariant & itemInfo,
       const QList< QwtLegendData > & data) [pure virtual],  [slot]
       Update the entries for a plot item.

       Parameters
           itemInfo Info about an item
           data List of legend entry attributes for the item



Author
       Generated automatically by Doxygen for Qwt User's Guide from the source
       code.

Version 6.2.0                   Sun Jul 18 2021           QwtAbstractLegend(3)