最近因项目需要绘制蛛网图，雷达图，于是就参考了https://blog.csdn.net/chyuanrufeng/article/details/76222533的文章，在此基础上做以修改，达到了自己想要的效果。在此感谢这位博主的分享，话不多说上代码。
实现的效果图:
源码如下
RadarChart.h
#ifndef RADARCHART_H
#define RADARCHART_H
#include <QWidget>
#include <QPainter>
#include <QPainterPath>
#include "qmath.h"
enum RadarType
{
Radar, //雷达图
Spider //蛛网图
};
enum PointTpye
{
ScatterPoints, //散点图
LinePoints //连线图
};
struct RadarData
{
RadarData(const QString& _name,const qreal &_value){ name = _name;value=_value;}
QString name;
qreal value;
};
#define PI M_PI
class RadarChart : public QWidget
{
Q_OBJECT
public:
explicit RadarChart(QWidget *parent = 0);
void setRadarType(RadarType radartype);
void setPointTpye(PointTpye pointstype);
void setRadialAxisLabelVisible(bool visible){ m_showRadialAxisLabel = visible;this->update();}
void setAngularAxisLabelVisible(bool visible){ m_showAngularAxisLabel = visible;this->update();}
void setTitle(const QString &title){ m_title = title;this->update(); }
void setTitleFont(const QFont &titleFont){ m_titleFont = titleFont; this->update();}
void setTitleColor(const QColor &titleColor){ m_titleColor = titleColor; this->update();}
void setDatas(const QList<RadarData> &datas);
void setTickCount(int tickCount){ m_tickCount = tickCount; this->update();}
void setAxisRange(qreal min,qreal max);
void setAngularLineColor(const QColor &color){ m_AngularLineColor = color;this->update();}
void setRadialLineColor(const QColor &color){ m_RadialLineColor = color;this->update();}
void setAngularLabelColor(const QColor &color){ m_AngularLabelColor = color;this->update();}
void setRadialLabelColor(const QColor &color){ m_RadialLabelColor = color;this->update();}
void setSeriesColor(const QColor &color){ m_seriesColor = color;this->update();
void setbackgroundColor(const QColor &color){ m_backgroundColor = color;this->update();}
void setLabelFont(const QFont &labelFont){ m_labelFont = labelFont; this->update();}
protected:
void paintEvent(QPaintEvent *event);
private:
void init();
void drawTitle(QPainter *painter);
void drawRadarType(QPainter *painter);
void drawRadar(QPainter *painter);
void drawSpider(QPainter *painter);
void drawRadialLabel(QPainter *painter);
void drawAngularLabel(QPainter *painter);
void drawData(QPainter *painter);
void drawScatterPoints(QPainter *painter);
void drawLinePoints(QPainter *painter);
private:
RadarType m_radartype;
PointTpye m_pointstype;
bool m_showRadialAxisLabel;
bool m_showAngularAxisLabel;
QString m_title;
QFont m_titleFont;
QColor m_titleColor;
QList<RadarData> m_datas;
int m_tickCount;
int m_AngularCount;
qreal m_Axis_min;
qreal m_Axis_max;
QColor m_AngularLineColor;
QColor m_RadialLineColor;
QColor m_AngularLabelColor;
QColor m_RadialLabelColor;
QColor m_seriesColor;
QColor m_backgroundColor;
QFont m_labelFont;
qreal m_titleHeight;
};
#endif // RADARCHART_H
RadarChart.cpp
#include "RadarChart.h"
RadarChart::RadarChart(QWidget *parent) : QWidget(parent)
{
init();
}
void RadarChart::setDatas(const QList<RadarData> &datas)
{
m_datas = datas;
m_AngularCount = m_datas.count();
this->update();
}
void RadarChart::setRadarType( RadarType radartype )
{
m_radartype = radartype;
this->update();
}
void RadarChart::setPointTpye( PointTpye pointstype )
{
m_pointstype = pointstype;
this->update();
}
void RadarChart::setAxisRange(qreal min,qreal max)
{
m_Axis_min = min;
m_Axis_max = max;
this->update();
}
void RadarChart::init()
{
m_radartype = Spider;
m_pointstype = LinePoints;
m_showRadialAxisLabel = true;
m_showAngularAxisLabel = true;
m_AngularCount = 0;
m_titleFont = QFont("Arial",12,QFont::Bold);
m_titleColor = Qt::black;
m_tickCount = 5;
m_Axis_min = 0;
m_Axis_max = 10;
m_AngularLineColor = Qt::black;
m_RadialLineColor = Qt::black;
m_AngularLabelColor = Qt::black;
m_RadialLabelColor = Qt::black;
m_seriesColor = QColor(102,170,238);
m_labelFont = QFont("Arial",9);
m_backgroundColor = Qt::white;
}
void RadarChart::paintEvent( QPaintEvent *event )
{
QPainter painter(this);
painter.setRenderHint(QPainter::Antialiasing);
painter.setRenderHint(QPainter::SmoothPixmapTransform);
painter.setRenderHint(QPainter::TextAntialiasing);
//添加背景颜色
painter.save();
painter.setBrush(m_backgroundColor);
painter.drawRect(0,0,width(),height());
painter.restore();
drawTitle(&painter);
drawData(&painter);
drawRadarType(&painter);
drawRadialLabel(&painter);
drawAngularLabel(&painter);
QWidget::paintEvent(event);
}
void RadarChart::drawTitle(QPainter *painter)
{
painter->save();
QPen pen;
pen.setColor(m_titleColor);
painter->setPen(pen);
painter->setFont(m_titleFont);
qreal w = width();
QFontMetricsF fontMetrics(m_titleFont);
qreal strWidth = fontMetrics.width(m_title);
qreal strHeight = fontMetrics.height();
qreal cur_x,cur_y;
cur_x = w / 2 - strWidth / 2;
cur_y = 10 + strHeight;
m_titleHeight = cur_y + 5;
painter->drawText(cur_x,cur_y,m_title);
painter->restore();
}
void RadarChart::drawRadarType( QPainter *painter )
{
switch (m_radartype)
{
case Radar:drawRadar(painter);break;
case Spider:drawSpider(painter);break;
default:drawRadar(painter);break;
}
}
void RadarChart::drawRadar( QPainter *painter )
{
painter->save();
QPen pen;
pen.setWidthF(0.4);
pen.setColor(m_AngularLineColor);
painter->setPen(pen);
qreal w = width();
qreal h = height() - m_titleHeight;
//绘制环线
qreal radius = qMin(w,h)/2; //半径
qreal step = radius/(m_tickCount+1); //每环之间的距离
qreal x0 = w/2 ; //中心点X坐标
qreal y0 = h/2 + m_titleHeight; //中心点Y坐标
qreal cur_x,cur_y;
QPainterPath loopPath;
for (int i = 1; i < m_tickCount+1; ++i)
{
qreal curRadius = step*i;
loopPath.addEllipse(QPointF(x0, y0), curRadius, curRadius);
}
painter->drawPath(loopPath);
pen.setColor(m_RadialLineColor);
painter->setPen(pen);
//绘制中心到边缘的直线
qreal dRadian = PI*2 / m_AngularCount; //每个环形标签之间的夹角
for (int i = 0 ; i < m_AngularCount; ++i)
{
cur_x = x0 + radius*qSin(dRadian*i);
cur_y = y0 - radius*qCos(dRadian*i);
painter->drawLine(x0,y0,cur_x,cur_y);
}
painter->restore();
}
void RadarChart::drawSpider( QPainter *painter )
{
painter->save();
QPen pen;
pen.setWidthF(0.4);
pen.setColor(m_AngularLineColor);
painter->setPen(pen);
qreal w = width();
qreal h = height() - m_titleHeight;
qreal radius = qMin(w,h)/2;
qreal step = radius/(m_tickCount+1);
qreal dRadian = PI*2 / m_AngularCount;
qreal x0 = w/2 ;
qreal y0 = h/2 + m_titleHeight;
qreal cur_x,cur_y;
QPointF *points = new QPointF[m_AngularCount + 1];
for (int j = 1 ; j < m_tickCount + 1; ++j)
{
qreal curRadius = step*j;
for (int i = 0 ; i < m_AngularCount; ++i)
{
cur_x = x0 + curRadius*qSin(dRadian*i);
cur_y = y0 - curRadius*qCos(dRadian*i);
points[i] = QPointF(cur_x,cur_y);
}
points[m_AngularCount] = points[0];
painter->drawPolyline(points,m_AngularCount + 1);
}
pen.setColor(m_RadialLineColor);
painter->setPen(pen);
for (int i = 0 ; i < m_AngularCount; ++i)
{
painter->drawLine(x0,y0,points[i].x(),points[i].y());
}
delete []points;
painter->restore();
}
void RadarChart::drawRadialLabel( QPainter *painter )
{
if (!m_showRadialAxisLabel) return;
painter->save();
qreal w = width();
qreal h = height() - m_titleHeight;
qreal radius = qMin(w,h)/2;
qreal step = radius/(m_tickCount+1);
qreal x0 = w/2 ;
qreal y0 = h/2 + m_titleHeight;
qreal cur_x,cur_y;
QPen pen;
pen.setColor(m_RadialLabelColor);
painter->setPen(pen);
painter->setFont(m_labelFont);
qreal dY = (m_Axis_max - m_Axis_min)/(m_tickCount);
qreal offset = 20;
if( step < 40 )
offset = step / 2;
for (int j = 0 ; j < m_tickCount+1; ++j)
{
qreal curRadius = step*j;
cur_x = x0 + 2;
cur_y = y0 - curRadius + offset;
qreal value = m_Axis_min + dY * j;
QString str = QString::number(value,'f',2);
painter->drawText(cur_x,cur_y,str);
}
painter->restore();
}
void RadarChart::drawAngularLabel( QPainter *painter )
{
if (!m_showAngularAxisLabel) return;
painter->save();
qreal w = width();
qreal h = height() - m_titleHeight;
qreal radius = qMin(w,h)/2;
qreal x0 = w/2 ;
qreal y0 = h/2 + m_titleHeight;
qreal newRadius = m_tickCount * radius/(m_tickCount+1) + 5;
qreal cur_x,cur_y;
qreal dRadian = PI*2 / m_AngularCount;
QPen pen;
pen.setColor(m_RadialLabelColor);
painter->setPen(pen);
painter->setFont(m_labelFont);
QFontMetricsF fontMetrics(m_labelFont);
qreal strWidth,strHeight;
qreal dError;
for (int i = 0 ; i < m_AngularCount; ++i)
{
cur_x = x0 + newRadius*qSin(dRadian*i);
cur_y = y0 - newRadius*qCos(dRadian*i);
strWidth = fontMetrics.width(m_datas.at(i).name);
strHeight = fontMetrics.height();
dError = abs(cur_x - x0);
if( dError < 1e-8 ) //cur_x == x0
cur_x -= strWidth / 2;
else
{
if( cur_x < x0 )
cur_x = cur_x - strWidth - 2;
else if( cur_x > x0 )
cur_x += 2;
}
dError = abs(cur_y - y0);
if( dError < 1e-8 ) //cur_y == y0
cur_y += strHeight / 2;
else
{
if( cur_y > y0 )
cur_y -= strHeight *qCos(dRadian*i) ;
else if( cur_y < y0 )
cur_y = cur_y - strHeight *qCos(dRadian*i) + strHeight;
}
painter->drawText(cur_x,cur_y,m_datas.at(i).name);
}
painter->restore();
}
void RadarChart::drawData( QPainter *painter )
{
switch(m_pointstype)
{
case ScatterPoints:drawScatterPoints(painter);break;
case LinePoints:drawLinePoints(painter);break;
default:drawLinePoints(painter);break;
}
}
void RadarChart::drawScatterPoints( QPainter *painter )
{
painter->save();
qreal w = width();
qreal h = height() - m_titleHeight;
qreal radius = qMin(w,h)/2;
qreal x0 = w/2 ;
qreal y0 = h/2 + m_titleHeight;
radius = m_tickCount * radius/(m_tickCount+1);
qreal cur_x,cur_y;
qreal dRadian = PI*2 / m_AngularCount;
qreal step = 1.0*radius/(m_Axis_max-m_Axis_min);
painter->setPen(m_seriesColor.darker(200));
painter->setBrush(m_seriesColor.darker(200));
for( int i = 0; i < m_AngularCount ; i++ )
{
qreal valueLength = m_datas.at(i).value * step;
cur_x = x0 + valueLength*qSin(dRadian*i);
cur_y = y0 - valueLength*qCos(dRadian*i);
painter->drawEllipse(QPointF(cur_x,cur_y),4,4);
}
painter->restore();
}
void RadarChart::drawLinePoints( QPainter *painter )
{
painter->save();
qreal w = width();
qreal h = height() - m_titleHeight;
qreal radius = qMin(w,h)/2;
qreal x0 = w/2 ;
qreal y0 = h/2 + m_titleHeight;
radius = m_tickCount * radius/(m_tickCount+1);
qreal cur_x,cur_y;
qreal dRadian = PI*2 / m_AngularCount;
qreal step = 1.0*radius/(m_Axis_max-m_Axis_min);
painter->setPen(m_seriesColor.darker(200));
painter->setBrush(m_seriesColor.darker(200));
QPointF *points = new QPointF[m_AngularCount];
for( int i = 0; i < m_AngularCount ; i++ )
{
qreal valueLength = m_datas.at(i).value * step;
cur_x = x0 + valueLength*qSin(dRadian*i);
cur_y = y0 - valueLength*qCos(dRadian*i);
points[i] = QPointF(cur_x,cur_y);
painter->drawEllipse(QPointF(cur_x,cur_y),2,2);
}
painter->setBrush(m_seriesColor.lighter(100));
painter->drawPolygon(points,m_AngularCount);
painter->restore();
}
当然调用也很简单：
#include "mainwindow.h"
#include "RadarChart.h"
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
{
RadarChart * widget = new RadarChart(this);
QList<RadarData> datas;
datas<<RadarData("Jan",10)<<RadarData("Feb",30)<<RadarData("Mar",50)<<RadarData("Apr",90)<<RadarData("May",20);
widget->setDatas(datas);
widget->setAxisRange(0,100);
this->setCentralWidget(widget);
this->resize(600,600);
}
到这里就结束啦，希望能帮到大家~