qwt_plot_legenditem.h

/******************************************************************************
 * 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
 *
 * Modified by ChenZongYan in 2024 <czy.t@163.com>
 *   Summary of major modifications (see ChangeLog.md for full history):
 *   1. CMake build system & C++11 throughout.
 *   2. Core panner/ zoomer refactored:
 *        - QwtPanner → QwtCachePanner (pixmap-cache version)
 *        - New real-time QwtPlotPanner derived from QwtPicker.
 *   3. Zoomer supports multi-axis.
 *   4. Parasite-plot framework:
 *        - QwtFigure, QwtPlotParasiteLayout, QwtPlotTransparentCanvas,
 *        - QwtPlotScaleEventDispatcher, built-in pan/zoom on axis.
 *   5. New picker: QwtPlotSeriesDataPicker (works with date axis).
 *   6. Raster & color-map extensions:
 *        - QwtGridRasterData (2-D table + interpolation)
 *        - QwtLinearColorMap::stopColors(), stopPos() API rename.
 *   7. Bar-chart: expose pen/brush control.
 *   8. Amalgamated build: single QwtPlot.h / QwtPlot.cpp pair in src-amalgamate.
 *****************************************************************************/
 
#ifndef QWT_PLOT_LEGEND_ITEM_H
#define QWT_PLOT_LEGEND_ITEM_H
 
#include "qwt_global.h"
#include "qwt_plot_item.h"
 
class QFont;
 
class QWT_EXPORT QwtPlotLegendItem : public QwtPlotItem
{
public:
    enum BackgroundMode
    {
        LegendBackground,
 
        ItemBackground
    };
 
    explicit QwtPlotLegendItem();
    ~QwtPlotLegendItem() override;
 
    virtual int rtti() const override;
 
    void setAlignmentInCanvas(Qt::Alignment);
    Qt::Alignment alignmentInCanvas() const;
 
    void setOffsetInCanvas(Qt::Orientations, int numPixels);
    int offsetInCanvas(Qt::Orientation) const;
 
    void setMaxColumns(uint);
    uint maxColumns() const;
 
    void setMargin(int);
    int margin() const;
 
    void setSpacing(int);
    int spacing() const;
 
    void setItemMargin(int);
    int itemMargin() const;
 
    void setItemSpacing(int);
    int itemSpacing() const;
 
    void setFont(const QFont&);
    QFont font() const;
 
    void setBorderRadius(double);
    double borderRadius() const;
 
    void setBorderPen(const QPen&);
    QPen borderPen() const;
 
    void setBackgroundBrush(const QBrush&);
    QBrush backgroundBrush() const;
 
    void setBackgroundMode(BackgroundMode);
    BackgroundMode backgroundMode() const;
 
    void setTextPen(const QPen&);
    QPen textPen() const;
 
    virtual void draw(QPainter*, const QwtScaleMap& xMap, const QwtScaleMap& yMap, const QRectF& canvasRect) const override;
 
    void clearLegend();
 
    virtual void updateLegend(const QwtPlotItem*, const QList< QwtLegendData >&) override;
 
    virtual QRect geometry(const QRectF& canvasRect) const;
 
    virtual QSize minimumSize(const QwtLegendData&) const;
    virtual int heightForWidth(const QwtLegendData&, int width) const;
 
    QList< const QwtPlotItem* > plotItems() const;
    QList< QRect > legendGeometries(const QwtPlotItem*) const;
 
protected:
    virtual void drawLegendData(QPainter*, const QwtPlotItem*, const QwtLegendData&, const QRectF&) const;
 
    virtual void drawBackground(QPainter*, const QRectF& rect) const;
 
private:
    QWT_DECLARE_PRIVATE(QwtPlotLegendItem)
};
 
#endif