石家庄有做网站的公司吗,织梦小说网站源码,四川省德阳市建设招投标网站,大型seo公司本文为转载 原文链接#xff1a; 采用Qt快速绘制多条曲线#xff08;折线#xff09;#xff0c;跟随鼠标动态显示线上点的值#xff08;基于Qt的开源绘图控件QCustomPlot进行二次开发#xff09;
内容如下
QCustomPlot是一个开源的基于Qt的第三方绘图库#xff0c;能…本文为转载 原文链接 采用Qt快速绘制多条曲线折线跟随鼠标动态显示线上点的值基于Qt的开源绘图控件QCustomPlot进行二次开发
内容如下
QCustomPlot是一个开源的基于Qt的第三方绘图库能够绘制漂亮的2D图形。
QCustomPlot的官方网址Qt Plotting Widget QCustomPlot - Introduction
从官网下载QCustomPlot的源文件包括qcustomplot.h和qcustomplot.cpp。
本程序的源码下载地址 https://github.com/xiongxw/XCustomPlot.git
1 自定义鼠标显示跟随类XxwTracer和XxwTraceLine
XxwTracer用于在图表中显示鼠标所在位置的x,y值
XxwTraceLine用于在图中显示水平或垂直的虚线
头文件XxwTracer.h
#ifndef MYTRACER_H
#define MYTRACER_H#include QObject
#include qcustomplot.h///
/// \brief The XxwTracer class:在图表中显示鼠标所在位置的x,y值的追踪显示器
///
class XxwTracer : public QObject
{
Q_OBJECTpublic:
enum TracerType
{XAxisTracer,//依附在x轴上显示x值YAxisTracer,//依附在y轴上显示y值DataTracer//在图中显示x,y值
};explicit XxwTracer(QCustomPlot *_plot, TracerType _type, QObject *parent Q_NULLPTR);~XxwTracer();
void setPen(const QPen pen);
void setBrush(const QBrush brush);
void setText(const QString text);
void setLabelPen(const QPen pen);
void updatePosition(double xValue, double yValue);void setVisible(bool m_visible);protected:bool m_visible;//是否可见TracerType m_type;//类型QCustomPlot *m_plot;//图表QCPItemTracer *m_tracer;//跟踪的点QCPItemText *m_label;//显示的数值QCPItemLine *m_arrow;//箭头
};///
/// \brief The XxwCrossLine class:用于显示鼠标移动过程中的鼠标位置的直线
///
class XxwTraceLine : public QObject
{
public:enum LineType{VerticalLine,//垂直线HorizonLine, //水平线Both//同时显示水平和垂直线};explicit XxwTraceLine(QCustomPlot *_plot, LineType _type VerticalLine, QObject *parent Q_NULLPTR);~XxwTraceLine();void initLine();void updatePosition(double xValue, double yValue);void setVisible(bool vis){if(m_lineV)m_lineV-setVisible(vis);if(m_lineH)m_lineH-setVisible(vis);}protected:bool m_visible;//是否可见LineType m_type;//类型QCustomPlot *m_plot;//图表QCPItemStraightLine *m_lineV; //垂直线QCPItemStraightLine *m_lineH; //水平线
};#endif // MYTRACER_H源文件MyTracer.cpp
#include MyTracer.hXxwTracer::XxwTracer(QCustomPlot *_plot, TracerType _type, QObject *parent): QObject(parent),m_plot(_plot),m_type(_type)
{m_visible true;m_tracer Q_NULLPTR;// 跟踪的点m_label Q_NULLPTR;// 显示的数值m_arrow Q_NULLPTR;// 箭头if (m_plot){QColor clrDefault(Qt::red);QBrush brushDefault(Qt::NoBrush);QPen penDefault(clrDefault);// penDefault.setBrush(brushDefault);penDefault.setWidthF(0.5);m_tracer new QCPItemTracer(m_plot);m_tracer-setStyle(QCPItemTracer::tsCircle);m_tracer-setPen(penDefault);m_tracer-setBrush(brushDefault);m_label new QCPItemText(m_plot);m_label-setLayer(overlay);m_label-setClipToAxisRect(false);m_label-setPadding(QMargins(5, 5, 5, 5));m_label-setBrush(brushDefault);m_label-setPen(penDefault);m_label-position-setParentAnchor(m_tracer-position);
// m_label-setFont(QFont(宋体, 8));m_label-setFont(QFont(Arial, 8));m_label-setColor(clrDefault);m_label-setText();m_arrow new QCPItemLine(m_plot);QPen arrowPen(clrDefault, 1);m_arrow-setPen(penDefault);m_arrow-setLayer(overlay);m_arrow-setClipToAxisRect(false);m_arrow-setHead(QCPLineEnding::esSpikeArrow);//设置头部为箭头形状switch (m_type){case XAxisTracer:{m_tracer-position-setTypeX(QCPItemPosition::ptPlotCoords);m_tracer-position-setTypeY(QCPItemPosition::ptAxisRectRatio);m_tracer-setSize(7);m_label-setPositionAlignment(Qt::AlignTop | Qt::AlignHCenter);m_arrow-end-setParentAnchor(m_tracer-position);m_arrow-start-setParentAnchor(m_arrow-end);m_arrow-start-setCoords(0, 20);//偏移量break;}case YAxisTracer:{m_tracer-position-setTypeX(QCPItemPosition::ptAxisRectRatio);m_tracer-position-setTypeY(QCPItemPosition::ptPlotCoords);m_tracer-setSize(7);m_label-setPositionAlignment(Qt::AlignRight | Qt::AlignHCenter);m_arrow-end-setParentAnchor(m_tracer-position);m_arrow-start-setParentAnchor(m_label-position);m_arrow-start-setCoords(-20, 0);//偏移量break;}case DataTracer:{m_tracer-position-setTypeX(QCPItemPosition::ptPlotCoords);m_tracer-position-setTypeY(QCPItemPosition::ptPlotCoords);m_tracer-setSize(5);m_label-setPositionAlignment(Qt::AlignLeft | Qt::AlignVCenter);m_arrow-end-setParentAnchor(m_tracer-position);m_arrow-start-setParentAnchor(m_arrow-end);m_arrow-start-setCoords(20, 0);break;}default:break;}setVisible(false);}
}XxwTracer::~XxwTracer()
{if(m_plot){if (m_tracer)m_plot-removeItem(m_tracer);if (m_label)m_plot-removeItem(m_label);if (m_arrow)m_plot-removeItem(m_arrow);}
}void XxwTracer::setPen(const QPen pen)
{if(m_tracer)m_tracer-setPen(pen);if(m_arrow)m_arrow-setPen(pen);
}void XxwTracer::setBrush(const QBrush brush)
{if(m_tracer)m_tracer-setBrush(brush);
}void XxwTracer::setLabelPen(const QPen pen)
{if(m_label){m_label-setPen(pen);m_label-setBrush(Qt::NoBrush);m_label-setColor(pen.color());}
}void XxwTracer::setText(const QString text)
{if(m_label)m_label-setText(text);
}void XxwTracer::setVisible(bool vis)
{m_visible vis;if(m_tracer)m_tracer-setVisible(m_visible);if(m_label)m_label-setVisible(m_visible);if(m_arrow)m_arrow-setVisible(m_visible);
}void XxwTracer::updatePosition(double xValue, double yValue)
{if (!m_visible){setVisible(true);m_visible true;}if (yValue m_plot-yAxis-range().upper)yValue m_plot-yAxis-range().upper;switch (m_type){case XAxisTracer:{m_tracer-position-setCoords(xValue, 1);m_label-position-setCoords(0, 15);m_arrow-start-setCoords(0, 15);m_arrow-end-setCoords(0, 0);setText(QString::number(xValue));break;}case YAxisTracer:{m_tracer-position-setCoords(0, yValue);m_label-position-setCoords(-20, 0);
// m_arrow-start-setCoords(20, 0);
// m_arrow-end-setCoords(0, 0);setText(QString::number(yValue));break;}case DataTracer:{m_tracer-position-setCoords(xValue, yValue);m_label-position-setCoords(20, 0);setText(QString(x:%1,y:%2).arg(xValue).arg(yValue));break;}default:break;}
}XxwTraceLine::XxwTraceLine(QCustomPlot *_plot, LineType _type, QObject *parent): QObject(parent),m_type(_type),m_plot(_plot)
{m_lineV Q_NULLPTR;m_lineH Q_NULLPTR;initLine();
}XxwTraceLine::~XxwTraceLine()
{if(m_plot){if (m_lineV)m_plot-removeItem(m_lineV);if (m_lineH)m_plot-removeItem(m_lineH);}
}void XxwTraceLine::initLine()
{if(m_plot){QPen linesPen(Qt::red, 1, Qt::DashLine);if(VerticalLine m_type || Both m_type){m_lineV new QCPItemStraightLine(m_plot);//垂直线m_lineV-setLayer(overlay);m_lineV-setPen(linesPen);m_lineV-setClipToAxisRect(true);m_lineV-point1-setCoords(0, 0);m_lineV-point2-setCoords(0, 0);}if(HorizonLine m_type || Both m_type){m_lineH new QCPItemStraightLine(m_plot);//水平线m_lineH-setLayer(overlay);m_lineH-setPen(linesPen);m_lineH-setClipToAxisRect(true);m_lineH-point1-setCoords(0, 0);m_lineH-point2-setCoords(0, 0);}}
}void XxwTraceLine::updatePosition(double xValue, double yValue)
{if(VerticalLine m_type || Both m_type){if(m_lineV){m_lineV-point1-setCoords(xValue, m_plot-yAxis-range().lower);m_lineV-point2-setCoords(xValue, m_plot-yAxis-range().upper);}}if(HorizonLine m_type || Both m_type){if(m_lineH){m_lineH-point1-setCoords(m_plot-xAxis-range().lower, yValue);m_lineH-point2-setCoords(m_plot-xAxis-range().upper, yValue);}}
}2 自定义的图表类XCustomPlot
XCustomPlot是基于QCustomPlot二次开发的图表类在鼠标移动过程中动态显示曲线上点的值。
头文件XCustomPlot.h
#ifndef XCUSTOMPLOT_H
#define XCUSTOMPLOT_H#include XxwTracer.h
#include qcustomplot.h
#include QObject
#include QListclass XxwCustomPlot:public QCustomPlot
{Q_OBJECTpublic:XxwCustomPlot(QWidget *parent 0);protected:virtual void mouseMoveEvent(QMouseEvent *event);public:////// \brief 设置是否显示鼠标追踪器/// \param show:是否显示///void showTracer(bool show){m_isShowTracer show;if(m_xTracer)m_xTracer-setVisible(m_isShowTracer);foreach (XxwTracer *tracer, m_dataTracers){if(tracer)tracer-setVisible(m_isShowTracer);}if(m_lineTracer)m_lineTracer-setVisible(m_isShowTracer);}////// \brief 是否显示鼠标追踪器/// \return///bool isShowTracer(){return m_isShowTracer;};private:bool m_isShowTracer;//是否显示追踪器鼠标在图中移动显示对应的值XxwTracer *m_xTracer;//x轴XxwTracer *m_yTracer;//y轴QListXxwTracer * m_dataTracers;//XxwTraceLine *m_lineTracer;//直线
};#endif // XCUSTOMPLOT_H源文件XCustomPlot.h
#include XxwCustomPlot.hXxwCustomPlot::XxwCustomPlot(QWidget *parent):QCustomPlot(parent),m_isShowTracer(false),m_xTracer(Q_NULLPTR),m_yTracer(Q_NULLPTR),m_dataTracers(QListXxwTracer *()),m_lineTracer(Q_NULLPTR)
{
}void XxwCustomPlot::mouseMoveEvent(QMouseEvent *event)
{QCustomPlot::mouseMoveEvent(event);if(m_isShowTracer){//当前鼠标位置像素坐标int x_pos event-pos().x();int y_pos event-pos().y();//像素坐标转成实际的x,y轴的坐标float x_val this-xAxis-pixelToCoord(x_pos);float y_val this-yAxis-pixelToCoord(y_pos);if(Q_NULLPTR m_xTracer)m_xTracer new XxwTracer(this, XxwTracer::XAxisTracer);//x轴m_xTracer-updatePosition(x_val, y_val);if(Q_NULLPTR m_yTracer)m_yTracer new XxwTracer(this, XxwTracer::YAxisTracer);//y轴m_yTracer-updatePosition(x_val, y_val);int nTracerCount m_dataTracers.count();int nGraphCount graphCount();if(nTracerCount nGraphCount){for(int i nTracerCount; i nGraphCount; i){XxwTracer *tracer new XxwTracer(this, XxwTracer::DataTracer);m_dataTracers.append(tracer);}}else if(nTracerCount nGraphCount){for(int i nGraphCount; i nTracerCount; i){XxwTracer *tracer m_dataTracers[i];if(tracer){tracer-setVisible(false);}}}for (int i 0; i nGraphCount; i){XxwTracer *tracer m_dataTracers[i];if(!tracer)tracer new XxwTracer(this, XxwTracer::DataTracer);tracer-setVisible(true);tracer-setPen(this-graph(i)-pen());tracer-setBrush(Qt::NoBrush);tracer-setLabelPen(this-graph(i)-pen());auto iter this-graph(i)-data()-findBegin(x_val);double value iter-mainValue();
// double value this-graph(i)-data()-findBegin(x_val)-value;tracer-updatePosition(x_val, value);}if(Q_NULLPTR m_lineTracer)m_lineTracer new XxwTraceLine(this,XxwTraceLine::Both);//直线m_lineTracer-updatePosition(x_val, y_val);this-replot();//曲线重绘}
}
3 使用自定义图表类XCustomPlot
在需要绘图的地方使用代码如下 m_customPlot new XxwCustomPlot();m_customPlot-showTracer(true);// add title layout element:m_customPlot-plotLayout()-insertRow(0);m_customPlot-plotLayout()-addElement(0, 0, new QCPTextElement(m_customPlot, 标题, QFont(黑体, 12, QFont::Bold)));m_customPlot-legend-setVisible(true);QFont legendFont font(); // start out with MainWindows font..legendFont.setPointSize(9); // and make a bit smaller for legendm_customPlot-legend-setFont(legendFont);m_customPlot-legend-setBrush(QBrush(QColor(255,255,255,230)));// by default, the legend is in the inset layout of the main axis rect. So this is how we access it to change legend placement:m_customPlot-axisRect()-insetLayout()-setInsetAlignment(0, Qt::AlignTop|Qt::AlignCenter);// make left and bottom axes always transfer their ranges to right and top axes:connect(m_customPlot-xAxis, SIGNAL(rangeChanged(QCPRange)), m_customPlot-xAxis2, SLOT(setRange(QCPRange)));connect(m_customPlot-yAxis, SIGNAL(rangeChanged(QCPRange)), m_customPlot-yAxis2, SLOT(setRange(QCPRange)));// Allow user to drag axis ranges with mouse, zoom with mouse wheel and select graphs by clicking:m_customPlot-setInteractions(QCP::iRangeDrag | QCP::iRangeZoom | QCP::iSelectPlottables);// generate some data:int nCount 100;QVectordouble x(nCount), y0(nCount), y1(nCount); // initialize with entries 0..100for (int i 0; i nCount; i){x[i] i; // x goes from -1 to 1y0[i] qSin(i * 10.0f / nCount); //siny1[i] qCos(i * 10.0f / nCount); //cos}// create graph and assign data to it:QPen pen;int i 1;QCPGraph *pGraph m_customPlot-addGraph();// m_customPlot-graph(0)-setData(x, y0);pGraph-setName(sin曲线);pGraph-setData(x,y0);pGraph-setPen(QPen(Qt::blue));pGraph m_customPlot-addGraph();// m_customPlot-graph(0)-setData(x, y0);pGraph-setName(cos曲线);pGraph-setData(x,y1);pGraph-setPen(QPen(Qt::darkYellow));// give the axes some labels:m_customPlot-xAxis-setLabel(x);m_customPlot-yAxis-setLabel(y);// set axes ranges, so we see all data:
// m_customPlot-xAxis-setRange(-1, 1);
// m_customPlot-yAxis-setRange(0, 1);m_customPlot-rescaleAxes(true);m_customPlot-replot();
4 效果图
