It's done , But it's troublesome to transplant later , No longer use this method , change to the use of sth.
https://blog.csdn.net/qq_27620407/article/details/108734088 such

Let's take a look at the preview , Just finished writing callout, So it highlights this , Let's start describing the functions one by one .

Qchart I read some articles on this one , Is to integrate various functions you need into your own classes . Inheritance didn't learn well , This is really hard for me , Other difficulties are how to realize the functions of each part , This is relatively easy to find by searching .

Class structure ：
Mychart–>Callot–>Mychart
|______________|
Because of my C++ Inheritance is not very good , The convenience of inheritance will be a little messy .
● It's basically the first step Mychart Inherit QChart, Then add some of your own content .
●Callout Use Mychart Instead of using it directly QChart Because , hold Call Oh, my God MychartView when , I wrote it myself connect There is no way to hide the dialog box of coordinates after the mouse leaves , Will always show , Only use other people's structures .
Callout Inheritance is QGraphicsItem, This class can directly copy the... In the official routine Callout file , Then make some changes , That's what I did .
● Then is MychartView, This is more difficult , It is also a point of my overall transformation of thinking . This one says , take your time .

Mychart

First, the parent class QChart, After the configuration of this class is completed, a show Function can directly display a curve , This curve contains the curve itself 、 Axis 、 Grid in background 、 Legend, etc , In this case, I use these functions .

Let's start constructing this first class , After the implementation of this class, you can use QChartView Call the custom class to realize the above functions , although Qchart The same effect can be achieved , But this class is simple , Let's practice first .

from H The document says

Variable ：

// It's necessary 
  QLineSeries *m_series; // Curve data 
  QList<QLineSeries *> m_serieslist;   // Curve list ,splineseries Is a smooth curve  QLineSeries  Broken line 
  int m_SeriesNum;   // Number of curves 
  QChart *m_Chart;        // Show 
  // Non essential 
  QStringList m_titles;             // title 
            // The following is for the coordinate axis 
  QValueAxis *axisX;             //x Axis 
  QValueAxis *axisY;             //y Axis 
  qreal m_x;
  qreal m_y;
            // The coordinate axis is used for automatic adjustment 
  int m_Max_AllValue;        // Maximum value of all images 
  int m_Min_AllValue;        // Minimum value of all images 
  QList<qreal *> m_Max_Ser;// The maximum value of each image 
  QList<qreal *> m_Min_Ser;// Minimum value of each image 
  QList<qreal *> m_SectionMax_Ser;// Maximum value of image interval 
  QList<qreal *> m_SectionMin_Ser;// Minimum value of image interval 
  QList<int *> m_axisXMax;// Number of data per image  

There are some useless variables , Consider this for yourself , Talk about the more important .

1、QChart *m_Chart;

This will replace... In future use Mychart As a real substitute QChart, This is what I didn't think of at first , Lead to the back Mychart Really Qchart Use , Wasted a lot of effort , It can also be seen from this that , The class I define now is actually in the original QChcart On the basis of a shell , This class can implement Qchart All functions of , With some pairs of Qchart The operation of ,m_Chart Is the body of the curve .
, Here I recommend the article I read at that time , You'd better look directly at , Don't look at my
https://blog.csdn.net/qq_31073871/article/details/82987524
Here to Qchart The use of is very good , Novices can get it out directly .

2、 QLineSeries *m_series; and QList<QLineSeries *> m_serieslist;

QLineSeries *m_series; // Curve data
QList<QLineSeries *> m_serieslist; // Curve list ,splineseries Is a smooth curve QLineSeries Broken line

m_series Is actually displayed , The curve is m_series, Other background axes are Qchart The content of .
The first premise of displaying the curve , take m_series Add to Qchart in , The second one is for m_series Write data .
Join only once , Then you can give m_series Write data ,Qchart It will update automatically .
m_series Add to Qchart in ： m_Chart->addSeries(m_series);
to m_series Write data ：m_series->append(x,y);
m_series In practical use, it is generally used QList<QLineSeries *> m_serieslist Instead of
take m_series Join in m_serieslist in m_serieslist.append(series);
Add to Qchart m_Chart->addSeries(m_serieslist[m_SeriesNum]);
Write data m_serieslist[lineNum]->append(x,y);

3、 Axis variables

QValueAxis *axisX; //x Axis
QValueAxis *axisY; //y Axis
These two are used to display the coordinate axis , And these two are yes Axis
qreal m_x;
qreal m_y;
It's actually used for punctuation

function

Just a few simple

1、 Click the legend to hide

  void connectMarkers();     // Connect 
  void disconnectMarkers();  // disconnect 
  void handleMarkerClicked(); // Functions executed after connection 

It is recommended to copy the function body directly , See the appendix at the end of the article

void Mychart::connectMarkers()
{
    
    // Connect all markers to handler
    const auto markers = m_Chart->legend()->markers();
    for (QLegendMarker *marker : markers) {
    
        // Disconnect possible existing connection to avoid multiple connections
        QObject::disconnect(marker, &QLegendMarker::clicked,
                            this, &Mychart::handleMarkerClicked);
        QObject::connect(marker, &QLegendMarker::clicked, this, &Mychart::handleMarkerClicked);
    }
}
void Mychart::disconnectMarkers()
{
    
    const auto markers = m_Chart->legend()->markers();
    for (QLegendMarker *marker : markers) {
    
        QObject::disconnect(marker, &QLegendMarker::clicked,
                            this, &Mychart::handleMarkerClicked);
    }
}
void Mychart::handleMarkerClicked()
{
    
    QLegendMarker* marker = qobject_cast<QLegendMarker*> (sender());
    Q_ASSERT(marker);
    switch (marker->type())
    {
    
        case QLegendMarker::LegendMarkerTypeXY:
        {
    
        // Toggle visibility of series
        marker->series()->setVisible(!marker->series()->isVisible());
        // Turn legend marker back to visible, since hiding series also hides the marker
        // and we don't want it to happen now.
        marker->setVisible(true);
        // Dim the marker, if series is not visible
        qreal alpha = 1.0;
        if (!marker->series()->isVisible())
            alpha = 0.5;
        QColor color;
        QBrush brush = marker->labelBrush();
        color = brush.color();
        color.setAlphaF(alpha);
        brush.setColor(color);
        marker->setLabelBrush(brush);

        brush = marker->brush();
        color = brush.color();
        color.setAlphaF(alpha);
        brush.setColor(color);
        marker->setBrush(brush);

        QPen pen = marker->pen();
        color = pen.color();
        color.setAlphaF(alpha);
        pen.setColor(color);
        marker->setPen(pen);
        break;
        }
    default:
        {
    
        qDebug() << "Unknown marker type";
        break;
        }
    }
}

2、 To be continued .....

It's done , But it's troublesome to transplant later , No longer use this method , change to the use of sth.
https://blog.csdn.net/qq_27620407/article/details/108734088 such