Qt 画自定义饼图统计的例子

先给出结果图，这个例子是将各种事件分类然后统计的其比例，然后画饼图显示出来

这个是我仿照官方给的例子，让后自己理解后，修改的，要生成饼图，需要QT的 charts 支持，安装QT 没有选择这个的，需要下载这个模块，然后在.pro文件中年添加

QT += charts

首先重写饼图块，让鼠标悬浮在某个饼图块时，让这个块弹出来，然后显示块的信息，这个比较简单，如下所示

//头文件
#include 

QT_CHARTS_USE_NAMESPACE

class CustomSlice : public QPieSlice
{
    Q_OBJECT

public:
    CustomSlice(QString label, qreal value);

public Q_SLOTS:
    void showHighlight(bool show);

};

//cpp文件

#include "customslice.h"

QT_CHARTS_USE_NAMESPACE

CustomSlice::CustomSlice(QString label, qreal value)
    : QPieSlice(label, value)
{
    connect(this, &CustomSlice::hovered, this, &CustomSlice::showHighlight);
}

void CustomSlice::showHighlight(bool show)
{
    setLabelVisible(show);//显示标签
    setExploded(show); // 弹出
}

主体代码如下，主要是初始化饼图，创建饼图，为饼图块随机上色，为饼图数据的显示做排序，只需要调用接口函数把相应的数据塞进去即可生成可视化的饼图

statisticwindow.h

#ifndef STATISTICCHARTSWINDOW_H
#define STATISTICCHARTSWINDOW_H

#include 
#include 
#include 
#include 
#include 
#include 

class QPushButton;
class CustomSlice;
QT_CHARTS_USE_NAMESPACE

class StatisticChartsWindow : public QWidget
{
    Q_OBJECT
public:
    explicit StatisticChartsWindow(QWidget *parent = nullptr);
    ~StatisticChartsWindow();
    //创建一个饼图1
    void createPie1(QMap data, QString title);
    //创建一个饼图2
    void createPie2(QMap data, QString title);
    // 为饼图1添加块信息
    void appendSlice1(QString lable, int value);
    // 为饼图2添加块信息
    void appendSlice2(QString lable, int value);
    // 移除所有块信息
    void removeAllSlice();
    // 获取随机颜色为饼图的每个块上色
    Qt::GlobalColor getRandomColor();
    //获取排序后的数据
    QList> getsortListByValue(QMap &data);
    QVBoxLayout *VBoxLayout;

    QPieSeries *series1;
    QPieSeries *series2;
    QChart *chart1;
    QChart *chart2;
    QChartView *chartView1;
    QChartView *chartView2;
    QPushButton *closeButton;

    QList CustomSlice1List;
    QList CustomSlice2List;
    QList colorList;

signals:
    void closeSig();

public slots:
};

#endif // STATISTICCHARTSWINDOW_H

statisticwindow.cpp

#include "statisticwindow.h"
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include "customslice.h"
#include 
#include "pushbutton.h"

StatisticChartsWindow::StatisticChartsWindow(QWidget *parent) : QWidget(parent)
{
    VBoxLayout = new QVBoxLayout(this);
    series1 = new QPieSeries(this);// 饼图一
    chart1 = new QChart();
    chart1->setAnimationOptions(QChart::AllAnimations);
    chart1->legend()->setVisible(true);
    chart1->legend()->setAlignment(Qt::AlignRight);//设置标签在右侧
    chartView1 = new QChartView(chart1);

    series2 = new QPieSeries(this);// 饼图一
    chart2 = new QChart();
    chart2->setAnimationOptions(QChart::AllAnimations);
    chart2->legend()->setVisible(true);
    chart2->legend()->setAlignment(Qt::AlignRight);//设置标签在右侧

    chartView2 = new QChartView(chart2);

    //底部添加关闭按钮
    closeButton = new QPushButton("关闭", this);
    QHBoxLayout *hlayout = new QHBoxLayout();
    hlayout->addItem(new QSpacerItem(20, 20, QSizePolicy::Expanding, QSizePolicy::Minimum));
    hlayout->addWidget(closeButton);
    hlayout->addItem(new QSpacerItem(20, 20, QSizePolicy::Expanding, QSizePolicy::Minimum));

    //SC3C::Valwell::PushButton::initStyle(closeButton);
    QPalette palette = closeButton->palette();
    QColor color(19, 46, 74); // RGB红色
    palette.setColor(QPalette::Button, color);
    closeButton->setPalette(palette);
    closeButton->setStyleSheet("color: white;");

    colorList<chart()->setTheme(QChart::ChartThemeBlueCerulean);
    chartView2->chart()->setTheme(QChart::ChartThemeBlueCerulean);
    VBoxLayout->addWidget(chartView1);
    VBoxLayout->addWidget(chartView2);
    VBoxLayout->addLayout(hlayout);
    VBoxLayout->layout()->setSpacing(1);//底部添加关闭

    connect(closeButton, &QPushButton::clicked, [=]() {
        this->hide();
        emit closeSig();
    });
    this->setWindowFlags(this->windowFlags() | Qt::WindowCloseButtonHint);
    this->setStyleSheet("background-color: rgb(19, 46, 74);");
}

StatisticChartsWindow::~StatisticChartsWindow()
{
    if(chart1) {
        delete  chart1;
    }
    if(chart2) {
        delete  chart2;
    }
}

void StatisticChartsWindow::createPie1(QMap data, QString title)
{
    // 创建一个饼图系列
    series1->clear();
    int count=0; //计算总数
    QMap> map;

    for(auto it=data.begin(); it!=data.end(); it++) {
        count += it.value();
    }

    QList> sortList = getsortListByValue(data);// 根据条数比例排序，从大到小

    for(QMap map: sortList) {
        QString keyLable = map.firstKey();
        int num = map.value(keyLable);
        double ratio = num/1.0/count*100;

        QString ratioStr = QString::number(ratio, 'f', 1);
        QString lable = QString("%1,条数:%2,占比,%3%").arg(keyLable).arg(num).arg(ratioStr);
        appendSlice1(lable, num); // 添加到饼图中
    }
    // 创建一个新的图表并添加系列
    chart1->setTitle(title);
    //chart1->removeAllSeries();
    chart1->addSeries(series1);
}

void StatisticChartsWindow::createPie2(QMap data, QString title)
{
    // 创建一个饼图系列
    series2->clear();
    int count=0; //计算总数
    QMap> map;

    for(auto it=data.begin(); it!=data.end(); it++) {
        count += it.value();
    }

    QList> sortList = getsortListByValue(data);

    for(QMap map: sortList) {
        QString keyLable = map.firstKey();
        int num = map.value(keyLable);
        double ratio = num/1.0/count*100;

        QString ratioStr = QString::number(ratio, 'f', 1);
        QString lable = QString("%1,条数:%2,占比,%3%").arg(keyLable).arg(num).arg(ratioStr);
        appendSlice2(lable, num);
    }
    // 创建一个新的图表并添加系列
    chart2->setTitle(title);
    //chart2->removeAllSeries();
    chart2->addSeries(series2);
}

void StatisticChartsWindow::appendSlice1(QString lable, int value)
{
    CustomSlice *customSlice = new  CustomSlice(lable, value);
    customSlice->setBrush(QBrush(getRandomColor())); //设置填充颜色
    //customSlice->setPen(QPen(Qt::black)); //设置线条颜色

    CustomSlice1List.append(customSlice);
    *series1 << customSlice;
}

void StatisticChartsWindow::appendSlice2(QString lable, int value)
{
    CustomSlice *customSlice = new  CustomSlice(lable, value);
    customSlice->setBrush(QBrush(getRandomColor())); //设置填充颜色
    CustomSlice2List.append(customSlice);
    *series2 << customSlice;}

void StatisticChartsWindow::removeAllSlice()
{
    for(CustomSlice* custom: CustomSlice1List) {
        series1->remove(custom);
    }
    for(CustomSlice* custom: CustomSlice2List) {
        series2->remove(custom);
    }
    qDeleteAll(CustomSlice1List);
    qDeleteAll(CustomSlice2List);
    CustomSlice1List.clear();
    CustomSlice2List.clear();
}

Qt::GlobalColor StatisticChartsWindow::getRandomColor()
{
    int randomValue = QRandomGenerator::global()->bounded(0, colorList.size()-1);
    return colorList.takeAt(randomValue);
}

QList> StatisticChartsWindow::getsortListByValue(QMap &data)
{
    QList> sortList;
    QList valueList;
    for(auto it=data.begin(); it!=data.end(); it++) {
        if(!valueList.contains(it.value())) {
            valueList.append(it.value());
        }
    }
    //根据值逆序排序
    std::sort(valueList.begin(), valueList.end(), std::greater());

    for(int value: valueList) {
        for(QString key: data.keys(value)) {
            QMap map;
            map.insert(key, value);
            sortList.append(map);
        }
    }
    return sortList;
}

我的这个例子是，点击统计按钮之后，获取相应的数据，然后生成相应的饼图

    QObject::connect(ui.statisticsBtn, &QPushButton::clicked, [=]() {
        g_dataCache->setSystemLog(SC3C::eSystemLogType::QUERY_SYSTEMLOG, QString("成功"),"查看日志统计");
        StatisticChartsWindow window;
        if(StatisticWindow) {
            tableView->hide();
            StatisticWindow->show();
            return;
        }
        StatisticWindow = new StatisticChartsWindow(q);
        QObject::connect(StatisticWindow, &StatisticChartsWindow::closeSig, q, [=]() {
            tableView->show();
        });
        //  标签名，  数量
        QMap map1 = { };
        QMap map2 = { };
        int logType = ui.logType->currentData().toInt();
        int eventType = ui.eventType->currentData().toInt();
        QString Name = ui.operatorName->currentText();
        tableModel.second->setFilterOperator("所有");
        // 获取数据，map1表示饼图一需要的数据
        getEventTypeStatisticHash(map1, map2);
        //恢复之前显示的
        tableModel.second->setFilterType(logType, eventType);
        tableModel.second->setFilterOperator(Name);
        //SC3C::Valwell::Widget::setBackgroundCommon2WithMargins(window);
        StatisticWindow->setFixedSize(q->size());
        //StatisticWindow->setStyleSheet("background-color: transparent;");
        StatisticWindow->createPie1(map1, "事件类型统计");
        StatisticWindow->createPie2(map2, "日志类型统计");
        StatisticWindow->show();
        tableView->hide();
    });

只需要把map放入创建饼图的函数即可，map中对应的是QMap<标签名，数量>，也就是饼图右侧的标签

        StatisticWindow->createPie1(map1, "事件类型统计");
        StatisticWindow->createPie2(map2, "日志类型统计");

这样就可以出饼图了