【嵌入式——QT】Charts常见的图表的绘制

柱状图
- QBarSet
- QBarSeries
- QBarCategoryAxis
- 图示
饼图
堆叠柱状图
百分比柱状图
散点图和光滑曲线图
代码示例

柱状图

QBarSet

用于创建柱状图的数据集。

主要函数

setLabel()：设置数据集标签；
setLabelBrush()：设置标签的画刷；
setLabelColor()：设置标签的文字颜色；
setLabelFont()：设置标签的字体；
setBorderColor()：设置数据集的棒图边框颜色；
setBrush()：设置数据集的棒图画刷；
setColor()：设置数据集的棒图填充颜色；
setPen()：设置数据集的棒图边框画笔；
append()：添加一个数据到数据集；
insert()：在某个位置插入一个数据到数据集；
remove()：从某个位置开始删除一定数量的数据；
replace()：替换某个位置的数据；
at()：返回某个位置的数据；
count()：返回数据个数；
sum()：返回数据集内所有数据的和；

QBarSeries

柱状图序列，一个柱状图序列一般包含多个QBarSet数据集。
主要函数

setBarWidth()：设置数据棒的宽度；
setLabelsVisible()：设置数据棒的标签可见性；
setLabelsFormat()：设置数据棒的标签的格式；
setLabelsPosition()：设置数据棒的标签的位置；
setLabelsAngle()：设置数据棒的标签的角度；
append()：添加一个QBarSet数据集序列；
insert()：在某个位置插入一个QBarSet数据集到序列；
remove()：移除一个数据集，并删除数据集对象；
take()：移除出一个数据集，但是不删除数据集对象；
clear()：清除全部数据集，并删除数据集对象；
barSets()：返回数据集对象的列表；
count()：返回数据集个数；

QBarCategoryAxis

柱状图分类坐标，以文字标签形式表示的坐标。
主要函数

append()：添加一个类别到坐标轴；
insert()：在某个位置插入一个类别到坐标轴；
replace()：替换某个类别；
remove()：删除某个类别；
clear()：删除所有类别；
at()：返回某个索引位置的类别文字；
count()：返回类别的个数；
setCategories()：设置一个QStringList字符串列表作为坐标轴的类别文字，删除原来所有类别文字；
setMin()：设置坐标轴最小值；
setMax()：设置坐标轴最大值；
setRange()：设置坐标轴范围；

图示

在这里插入图片描述

饼图

在这里插入图片描述

堆叠柱状图

在这里插入图片描述

百分比柱状图

在这里插入图片描述

散点图和光滑曲线图

在这里插入图片描述

代码示例

QChartCommon.h

#ifndef QCHARTCOMMON_H
#define QCHARTCOMMON_H

#include <QMainWindow>
#include <QtCharts>

namespace Ui
{
    class QChartCommon;
}

#define fixedColumnCount 5 //列数
#define initDataRowCount 6 //学生个数
#define colNoName 0 //姓名列编号
#define colNoMath 1 //数学列编号
#define colNoChinese 2 //语文列编号
#define colNoEnglish 3 //英语列编号
#define colNoAverage 4 //平均分列编号



class QChartCommon : public QMainWindow
{
    Q_OBJECT

public:
    explicit QChartCommon(QWidget* parent = nullptr);
    ~QChartCommon();

    void initData();
    void initTreeWidget();
    void initBarChart();
    void buildBarChart();
    void initPieChart();
    void buildPieChart();
    void initStackedBar();
    void buildStackedBar();
    void initPercentBar();
    void buildPercentBar();
    void initScatterChart();
    void buildScatterChart();

public slots:
    void on_itemChanged(QStandardItem* item);
    void on_pieSliceHighlight(bool flag);
private slots:
    void on_tabWidget_currentChanged(int index);

    void on_comboBox_2_currentIndexChanged(int index);

    void on_pushButton_clicked();

    void on_comboBox_currentIndexChanged(int index);

private:
    Ui::QChartCommon* ui;
    QStandardItemModel* theModel;

    QChart* pieChart;
};

#endif // QCHARTCOMMON_H

QChartCommon.cpp

#include "QChartCommon.h"
#include "ui_QChartCommon.h"

#include <QTime>
QChartCommon::QChartCommon(QWidget* parent)
    : QMainWindow(parent)
    , ui(new Ui::QChartCommon)
{
    ui->setupUi(this);
    theModel = new QStandardItemModel(initDataRowCount, fixedColumnCount, this);
    initData();
    initTreeWidget();
    connect(theModel, SIGNAL(itemChanged(QStandardItem*)), this, SLOT(on_itemChanged(QStandardItem*)));
    ui->tableView->setModel(theModel);
    initBarChart();
    initPieChart();
    initStackedBar();
    initPercentBar();
    initScatterChart();
    on_tabWidget_currentChanged(0);
}

QChartCommon::~QChartCommon()
{
    delete ui;
}

void QChartCommon::initData()
{
    QStringList headerList;
    headerList<<u8"姓名"<<u8"数据"<<u8"语文"<<u8"英语"<<u8"平均分";
    theModel->setHorizontalHeaderLabels(headerList);
    qsrand(QTime::currentTime().second());
    for(int i=0; i<theModel->rowCount(); i++) {
        QString studName = QString::asprintf(u8"学生%2d", i+1);
        QStandardItem* aItem = new QStandardItem(studName);
        aItem->setTextAlignment(Qt::AlignHCenter);
        theModel->setItem(i, colNoName, aItem);
        qreal avgScore = 0;
        for(int j=colNoMath; j<=colNoEnglish; j++) {
            qreal score = 50.0+(qrand()%50);
            avgScore+=score;
            QStandardItem*  aItem1 = new QStandardItem(QString::asprintf("%.0f", score));
            aItem1->setTextAlignment(Qt::AlignHCenter);
            theModel->setItem(i, j, aItem1);
        }
        QStandardItem*  aItem2 = new QStandardItem(QString::asprintf("%.1f", avgScore/3));
        aItem2->setTextAlignment(Qt::AlignHCenter);
        theModel->setItem(i, colNoAverage, aItem2);
    }
}

void QChartCommon::initTreeWidget()
{
    QTreeWidgetItem* item1 = new QTreeWidgetItem(1001);
    item1->setText(0, u8"60分以下");
    item1->setText(1, u8"1");
    item1->setText(2, u8"1");
    item1->setText(3, u8"1");
    item1->setText(4, u8"1");
    item1->setFlags(Qt::ItemIsSelectable | Qt::ItemIsUserCheckable|Qt::ItemIsEnabled | Qt::ItemIsAutoTristate);
    ui->treeWidget->addTopLevelItem(item1);
    QTreeWidgetItem* item2 = new QTreeWidgetItem(1002);
    item2->setText(0, u8"60-69分");
    item2->setText(1, u8"2");
    item2->setText(2, u8"2");
    item2->setText(3, u8"2");
    item2->setText(4, u8"2");
    item2->setFlags(Qt::ItemIsSelectable | Qt::ItemIsUserCheckable|Qt::ItemIsEnabled | Qt::ItemIsAutoTristate);
    ui->treeWidget->addTopLevelItem(item2);
    QTreeWidgetItem* item3 = new QTreeWidgetItem(1003);
    item3->setText(0, u8"70-79分");
    item3->setText(1, u8"4");
    item3->setText(2, u8"3");
    item3->setText(3, u8"0");
    item3->setText(4, u8"6");
    item3->setFlags(Qt::ItemIsSelectable | Qt::ItemIsUserCheckable|Qt::ItemIsEnabled | Qt::ItemIsAutoTristate);
    ui->treeWidget->addTopLevelItem(item3);
    QTreeWidgetItem* item4 = new QTreeWidgetItem(1004);
    item4->setText(0, u8"80-89分");
    item4->setText(1, u8"1");
    item4->setText(2, u8"1");
    item4->setText(3, u8"2");
    item4->setText(4, u8"0");
    item4->setFlags(Qt::ItemIsSelectable | Qt::ItemIsUserCheckable|Qt::ItemIsEnabled | Qt::ItemIsAutoTristate);
    ui->treeWidget->addTopLevelItem(item4);
    QTreeWidgetItem* item5 = new QTreeWidgetItem(1005);
    item5->setText(0, u8"90分以上");
    item5->setText(1, u8"2");
    item5->setText(2, u8"0");
    item5->setText(3, u8"0");
    item5->setText(4, u8"0");
    item5->setFlags(Qt::ItemIsSelectable | Qt::ItemIsUserCheckable|Qt::ItemIsEnabled | Qt::ItemIsAutoTristate);
    ui->treeWidget->addTopLevelItem(item5);
}

//柱状图
void QChartCommon::initBarChart()
{
    QChart* chart = new QChart();
    chart->setTitle(u8"Barchart演示");
    chart->setAnimationOptions(QChart::SeriesAnimations);
    ui->graphicsViewBar->setChart(chart);
    ui->graphicsViewBar->setRenderHint(QPainter::Antialiasing);
}
//柱状图
void QChartCommon::buildBarChart()
{
    QChart* chart = ui->graphicsViewBar->chart();//获取关联的chart
    chart->removeAllSeries();//删除所有序列
    chart->removeAxis(chart->axisX());//删除X轴
    chart->removeAxis(chart->axisY());//删除Y轴
    QBarSet* setMath = new QBarSet(theModel->horizontalHeaderItem(colNoMath)->text());
    QBarSet* setChinese = new QBarSet(theModel->horizontalHeaderItem(colNoChinese)->text());
    QBarSet* setEnglish = new QBarSet(theModel->horizontalHeaderItem(colNoEnglish)->text());
    QLineSeries* line = new QLineSeries();
    line->setName(theModel->horizontalHeaderItem(colNoAverage)->text());
    QPen pen;
    pen.setColor(Qt::red);
    pen.setWidth(2);
    line->setPen(pen);
    for(int i=0; i<theModel->rowCount(); i++) {
        setMath->append(theModel->item(i, colNoMath)->text().toInt());
        setChinese->append(theModel->item(i, colNoChinese)->text().toInt());
        setEnglish->append(theModel->item(i, colNoEnglish)->text().toInt());
        line->append(QPointF(i, theModel->item(i, colNoMath)->text().toFloat()));
    }
    //柱状图序列
    QBarSeries* series = new QBarSeries();
    series->append(setMath);
    series->append(setChinese);
    series->append(setEnglish);
    chart->addSeries(series);
    chart->addSeries(line);
    //横坐标字符串
    QStringList categories;
    for(int i=0; i<theModel->rowCount(); i++) {
        categories<<theModel->item(i, colNoName)->text();
    }
    //横坐标
    QBarCategoryAxis* axisX = new QBarCategoryAxis();
    // axisX->append(categories);
    axisX->setCategories(categories);
    chart->setAxisX(axisX, series);
    chart->setAxisX(axisX, line);
    axisX->setRange(categories.at(0), categories.at(categories.count()-1));
    //纵坐标
    QValueAxis* axisY = new QValueAxis();
    axisY->setRange(0, 100);
    axisY->setTitleText(u8"分数");
    axisY->setTickCount(6);
    axisY->setLabelFormat("%.0f");
    chart->setAxisY(axisY, series);
    chart->setAxisY(axisY, line);
    chart->legend()->setVisible(true);
    chart->legend()->setAlignment(Qt::AlignBottom);
}

//饼图
void QChartCommon::initPieChart()
{
    pieChart = new QChart();
    pieChart->setTitle(u8"Piechart演示");
    pieChart->setAnimationOptions(QChart::SeriesAnimations);
    ui->graphicsViewPie->setChart(pieChart);
    ui->graphicsViewPie->setRenderHint(QPainter::Antialiasing);
    ui->comboBox->addItem(u8"数学", 0);
    ui->comboBox->addItem(u8"语文", 1);
    ui->comboBox->addItem(u8"英语", 2);
    ui->comboBox->addItem(u8"平均分", 3);
    ui->comboBox_2->addItem("ChartThemeLight", 0);
    ui->comboBox_2->addItem("ChartThemeBlueCerulean", 1);
    ui->comboBox_2->addItem("ChartThemeDark", 2);
    ui->comboBox_2->addItem("ChartThemeBrownSand", 3);
    ui->comboBox_2->addItem("ChartThemeBlueNcs", 4);
    ui->comboBox_2->addItem("ChartThemeHighContrast", 5);
    ui->comboBox_2->addItem("ChartThemeBlueIcy", 6);
    ui->comboBox_2->addItem("ChartThemeQt", 7);
    ui->doubleSpinBoxHole->setValue(0.20);
    ui->doubleSpinBoxPie->setValue(0.70);
}
//饼图
void QChartCommon::buildPieChart()
{
    QChart* chart = ui->graphicsViewPie->chart();
    chart->removeAllSeries();
    int colNo = 1+ui->comboBox->currentIndex();
    QPieSeries* series = new QPieSeries();
    //饼图中心空心的大小
    series->setHoleSize(ui->doubleSpinBoxHole->value());
    for(int i=0; i<=4; i++) {
        //添加分块数据
        QTreeWidgetItem* item = ui->treeWidget->topLevelItem(i);
        series->append(item->text(0), item->text(colNo).toFloat());
        // series->append(ui->comboBox->itemText(i), 25.0);
    }
    QPieSlice* slice;//饼图分块
    for(int i=0; i<=4; i++) {
        slice=series->slices().at(i);//获取分块
        slice->setLabel(slice->label()+QString::asprintf(u8": %.0f 人,%.1f%%", slice->value(), slice->percentage()*100));
        connect(slice, SIGNAL(hovered(bool)), this, SLOT(on_pieSliceHighlight(bool)));
    }
    //最后一个设置为exploded
    slice->setExploded(true);
    //必须添加完slice之后再设置
    series->setLabelsVisible(true);
    //添加饼图序列
    chart->addSeries(series);
    chart->setTitle("Piechart---"+ui->comboBox->currentText());
    chart->legend()->setVisible(true);
    chart->legend()->setAlignment(Qt::AlignRight);
}
//堆叠图
void QChartCommon::initStackedBar()
{
    QChart* chart = new QChart();
    chart->setTitle(u8"StackedBar演示");
    chart->setAnimationOptions(QChart::SeriesAnimations);
    ui->graphicsViewStacked->setChart(chart);
    ui->graphicsViewStacked->setRenderHint(QPainter::Antialiasing);
}
//堆叠图
void QChartCommon::buildStackedBar()
{
    QChart* chart = ui->graphicsViewStacked->chart();
    chart->removeAllSeries();
    chart->removeAxis(chart->axisX());
    chart->removeAxis(chart->axisY());
    QBarSet* setMath = new QBarSet(theModel->horizontalHeaderItem(colNoMath)->text());
    QBarSet* setChinese = new QBarSet(theModel->horizontalHeaderItem(colNoChinese)->text());
    QBarSet* setEnglish = new QBarSet(theModel->horizontalHeaderItem(colNoEnglish)->text());
    for(int i=0; i<theModel->rowCount(); i++) {
        //添加分数到数据集
        setMath->append(theModel->item(i, colNoMath)->text().toInt());
        setChinese->append(theModel->item(i, colNoChinese)->text().toInt());
        setEnglish->append(theModel->item(i, colNoEnglish)->text().toInt());
    }
    //创建QStackedBarSeries对象并添加数据集
    QStackedBarSeries* series = new QStackedBarSeries();
    series->append(setMath);
    series->append(setChinese);
    series->append(setEnglish);
    series->setLabelsVisible(true);
    chart->addSeries(series);
    QStringList categories;
    for(int i=0; i<theModel->rowCount(); i++) {
        categories<<theModel->item(i, colNoName)->text();
    }
    //创建横轴
    QBarCategoryAxis* axisX = new QBarCategoryAxis();
    axisX->setCategories(categories);
    chart->setAxisX(axisX);
    axisX->setRange(categories.at(0), categories.at(categories.count()-1));
    //创建Y轴
    QValueAxis* axisY = new QValueAxis();
    axisY->setRange(0, 300);
    axisY->setTitleText(u8"总分");
    axisY->setTickCount(6);
    axisY->setLabelFormat("%.0f");
    chart->setAxisY(axisY);
    chart->legend()->setVisible(true);
    chart->legend()->setAlignment(Qt::AlignTop);
}
//百分比柱状图
void QChartCommon::initPercentBar()
{
    QChart* chart = new QChart();
    chart->setTitle(u8"PercentBar演示");
    chart->setAnimationOptions(QChart::SeriesAnimations);
    ui->graphicsViewPercent->setChart(chart);
    ui->graphicsViewPercent->setRenderHint(QPainter::Antialiasing);
}
//百分比柱状图
void QChartCommon::buildPercentBar()
{
    QChart* chart = ui->graphicsViewPercent->chart();
    chart->removeAllSeries();
    chart->removeAxis(chart->axisX());
    chart->removeAxis(chart->axisY());
    QBarSet* setMath = new QBarSet(theModel->horizontalHeaderItem(colNoMath)->text());
    QBarSet* setChinese = new QBarSet(theModel->horizontalHeaderItem(colNoChinese)->text());
    QBarSet* setEnglish = new QBarSet(theModel->horizontalHeaderItem(colNoEnglish)->text());
    QTreeWidgetItem* item;
    QStringList categories;
    for(int i=0; i<=4; i++) {
        //添加分块数据
        item = ui->treeWidget->topLevelItem(i);
        categories<<item->text(0);
        setMath->append(item->text(colNoMath).toFloat());
        setChinese->append(item->text(colNoChinese).toFloat());
        setEnglish->append(item->text(colNoEnglish).toFloat());
    }
    QPercentBarSeries* series = new QPercentBarSeries();
    series->append(setMath);
    series->append(setChinese);
    series->append(setEnglish);
    series->setLabelsVisible(true);
    chart->addSeries(series);
    QBarCategoryAxis* axisX = new QBarCategoryAxis();
    axisX->setCategories(categories);
    chart->setAxisX(axisX);
    axisX->setRange(categories.at(0), categories.at(categories.count()-1));
    //创建Y轴
    QValueAxis* axisY = new QValueAxis();
    axisY->setRange(0, 100);
    axisY->setTitleText(u8"百分比");
    axisY->setTickCount(6);
    axisY->setLabelFormat("%.1f");
    chart->setAxisY(axisY, series);
    chart->legend()->setVisible(true);
    chart->legend()->setAlignment(Qt::AlignRight);
}
//散点图
void QChartCommon::initScatterChart()
{
    QChart* chart = new QChart();
    chart->setTitle(u8"ScatterChart演示");
    chart->setAnimationOptions(QChart::SeriesAnimations);
    ui->graphicsViewScatter->setChart(chart);
    ui->graphicsViewScatter->setRenderHint(QPainter::Antialiasing);
}
//散点图
void QChartCommon::buildScatterChart()
{
    QChart* chart = ui->graphicsViewScatter->chart();
    chart->removeAllSeries();
    chart->removeAxis(chart->axisX());
    chart->removeAxis(chart->axisY());
    QSplineSeries* seriesLine = new QSplineSeries();
    seriesLine->setName("spline");
    QPen pen;
    pen.setColor(Qt::blue);
    pen.setWidth(2);
    seriesLine->setPen(pen);
    QScatterSeries* series0 = new QScatterSeries();
    series0->setName(u8"散点");
    series0->setMarkerShape(QScatterSeries::MarkerShapeCircle);
    series0->setBorderColor(Qt::black);
    series0->setBrush(QBrush(Qt::red));
    series0->setMarkerSize(12);
    qsrand(QTime::currentTime().second());
    for(int i=0; i<10; i++) {
        int x = (qrand()%20);
        int y= (qrand()%20);
        series0->append(x, y); //散点序列
        seriesLine->append(x, y); //光滑曲线
    }
    chart->addSeries(series0);
    chart->addSeries(seriesLine);
    chart->createDefaultAxes();//创建缺省坐标轴
    chart->axisX()->setTitleText(u8"X轴");
    chart->axisX()->setRange(-2, 22);
    chart->axisY()->setTitleText(u8"Y轴");
    chart->axisY()->setRange(-2, 22);
    chart->legend()->setVisible(true);
    chart->legend()->setAlignment(Qt::AlignRight);
}

void QChartCommon::on_itemChanged(QStandardItem* item)
{
    if((item->column()<colNoMath) || (item->column()>colNoEnglish)) {
        return;
    }
    int rowNo = item->row();
    qreal avg = 0;
    QStandardItem* aItem;
    for(int i=colNoMath; i<=colNoEnglish; i++) {
        aItem = theModel->item(rowNo, i);
        avg += aItem->text().toDouble();
    }
    avg = avg/3;
    aItem = theModel->item(rowNo, colNoAverage);
    aItem->setText(QString::asprintf("%.1f", avg));
}

void QChartCommon::on_pieSliceHighlight(bool flag)
{
    QPieSlice* slice = (QPieSlice*)sender();
    slice->setExploded(flag);
}

void QChartCommon::on_tabWidget_currentChanged(int index)
{
    switch(index) {
        case 0:
            buildBarChart();
            break;
        case 1:
            buildPieChart();
            break;
        case 2:
            buildStackedBar();
            break;
        case 3:
            buildPercentBar();
            break;
        case 4:
            buildScatterChart();
            break;
    }
}


void QChartCommon::on_comboBox_2_currentIndexChanged(int index)
{
    switch(index) {
        case 0:
            pieChart->setTheme(QChart::ChartThemeLight);
            break;
        case 1:
            pieChart->setTheme(QChart::ChartThemeBlueCerulean);
            break;
        case 2:
            pieChart->setTheme(QChart::ChartThemeDark);
            break;
        case 3:
            pieChart->setTheme(QChart::ChartThemeBrownSand);
            break;
        case 4:
            pieChart->setTheme(QChart::ChartThemeBlueNcs);
            break;
        case 5:
            pieChart->setTheme(QChart::ChartThemeHighContrast);
            break;
        case 6:
            pieChart->setTheme(QChart::ChartThemeBlueIcy);
            break;
        case 7:
            pieChart->setTheme(QChart::ChartThemeQt);
            break;
    }
}


void QChartCommon::on_pushButton_clicked()
{
    buildPieChart();
}


void QChartCommon::on_comboBox_currentIndexChanged(int index)
{
    buildPieChart();
}