QT中QChart绘制折线图

目录

• 一、简单绘图
• 二、绘制折线图
• 实例

一、简单绘图

Qt Charts基于Qt的Graphics View架构，其核心组件是QChartView 和 QChart

• QChartView是显示图标的视图，基类为QGraphicsView
• QChart的基类是QGraphicsltem

类的继承关系：

创建项目：.pro文件中添加：QT += charts
代码如下：其他文件未修改，修改代码只在mainwindow.cpp文件中进行。
mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QChartView>
#include <QLineSeries>
#include <QValueAxis>
#include <QtMath>
QT_CHARTS_USE_NAMESPACE

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    setWindowTitle("QChart简单绘图");

    //创建图表框架
    QChartView* cview = new QChartView(this);
    QChart* chart = new QChart();
    chart->setTitle("简单函数曲线");

    cview->setChart(chart);
    setCentralWidget(cview);

    //创建折现序列
    QLineSeries* seriesS = new QLineSeries;
    QLineSeries* seriesC = new QLineSeries;
    seriesS->setName("Sinθ");
    seriesC->setName("Cosθ");
    chart->addSeries(seriesS);
    chart->addSeries(seriesC);

    //添加数据绘制
    qreal y0,y1,t=0,intv=0.1;
    size_t count=100;
    for (size_t i=0;i<count;i++) {
        y0 = qSin(t);
        y1 = qCos(t);
        seriesS->append(t,y0);
        seriesC->append(t,y1);
        t += intv;
    }

    //创建坐标轴
    QValueAxis* axisX = new QValueAxis;
    axisX->setRange(0,10);
    chart->setAxisX(axisX,seriesS);
    chart->setAxisX(axisX,seriesC);

    QValueAxis* axisY = new QValueAxis;
    axisY->setRange(-1, 1);
    chart->setAxisY(axisY,seriesS);
    chart->setAxisY(axisY,seriesC);

}

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

二、绘制折线图

数据序列类继承关系

坐标类继承关系

实例

初步UI设计

自定义DialogPen类

新建DialogPen类继承QDialog：

#ifndef DIALOGPEN_H
#define DIALOGPEN_H

#include <QDialog>
#include <QColorDialog>
#include <QPen>
#include <QPalette>

namespace Ui {
class DialogPen;
}

class DialogPen : public QDialog
{
    Q_OBJECT

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

    QPen getpen();
    static QPen getPen(QPen initPen, bool &ok);
    void setPen(const QPen &pen);

private slots:
    void on_pushButton_clicked();

private:
    QPen m_pen;
    Ui::DialogPen *ui;
};

#endif // DIALOGPEN_H

#include "dialogpen.h"
#include "ui_dialogpen.h"
#include <QString>

DialogPen::DialogPen(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::DialogPen)
{
    ui->setupUi(this);
    ui->comboBox->clear();
    ui->comboBox->addItem("NoPen",0);
    ui->comboBox->addItem("SolidLine",1);
    ui->comboBox->addItem("DashLine",2);
    ui->comboBox->addItem("DotLine",3);
    ui->comboBox->addItem("DashDotLine",4);
    ui->comboBox->addItem("DashDotDotLine",5);
    ui->comboBox->addItem("CustomDashLine",6);
    ui->comboBox->setCurrentIndex(0);
}

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

void DialogPen::on_pushButton_clicked()
{
    QColor color = m_pen.color();
    QColorDialog::getColor(color);
    if(color.isValid()){
        QString str = QString::asprintf("background-color: rgb(%d,%d,%d)",color.red(),color.green(),color.blue());
        ui->btnColor->setStyleSheet(str);
    }

}

QPen DialogPen::getpen()
{
    m_pen.setStyle(Qt::PenStyle(ui->comboBox->currentIndex()));
    m_pen.setWidth(ui->spinBox->value());
    QColor color = ui->btnColor->palette().color(QPalette::Button);
    m_pen.setColor(color);
    return m_pen;
}

QPen DialogPen::getPen(QPen initPen, bool &ok)
{
    DialogPen* dlg = new DialogPen;
    QPen pen;
    dlg->setPen(initPen);
    int ret = dlg->exec();
    if (ret == QDialog::Accepted){
        pen = dlg->getpen();
        ok = true;
    }else {
        pen = initPen;
        ok = false;
    }
    delete dlg;
    return pen;
}

void DialogPen::setPen(const QPen &pen)
{
    m_pen = pen;
    ui->spinBox->setValue(pen.width());
    int i = static_cast<int>(pen.style());
    ui->comboBox->setCurrentIndex(i);
    ui->btnColor->setAutoFillBackground(true);
    QColor color = pen.color();
    QString str = QString::asprintf("background-color: rgb(%d,%d,%d)",color.red(),color.green(),color.blue());
    ui->btnColor->setStyleSheet(str);
}

mainwindow类

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QChartView>
#include <QtCharts>
#include <QColor>
#include <QLineSeries>
#include <QValueAxis>
#include <QtMath>
#include <QTime>
#include <QChart>
#include <QFontDialog>
#include "dialogpen.h"

QT_CHARTS_USE_NAMESPACE

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

private slots:
    void on_actZoomOut_triggered();

    void on_actZoomIn_triggered();

    void on_actReset_triggered();

    void on_actFlush_triggered();

    void on_btn_set_clicked();

    void on_btn_titleFont_clicked();

    void on_rBtn_Up_clicked();

    void on_rBtn_Down_clicked();

    void on_rBtn_Left_clicked();

    void on_rBtn_Right_clicked();

    void on_checkBox_legend_clicked(bool checked);

    void on_checkBox_legendBG_clicked(bool checked);

    void on_pBtn_Font_clicked();

    void on_pBtn_legendcolor_clicked();

    void on_pBtn_setMargin_clicked();

    void on_comboBox_motion_currentIndexChanged(int index);

    void on_comboBox_theme_currentIndexChanged(int index);

    void on_sin_curve_clicked();

    void on_cos_curve_clicked();

    void on_pBtn_name_clicked();

    void on_checkBox_curve_clicked(bool checked);

    void on_checkBox_data_clicked(bool checked);

    void on_pBtn_color_clicked();

    void on_pBtn_pen_clicked();

    void on_horizontalSlider_valueChanged(int value);

    void on_checkBox_pointLableVisible_clicked(bool checked);

    void on_pushButton_13_clicked();

    void on_pushButton_12_clicked();

    void on_rBtn_Y_clicked();

    void on_rBtn_XY_clicked();

    void on_rBtn_XAxies_clicked();

    void on_rBtn_YAxies_clicked();

    void on_Axis_isVisible_clicked(bool checked);

    void on_Axis_range_clicked();

    void on_Axis_setTitle_clicked();

    void on_Axis_titleIsVisible_clicked(bool checked);

    void on_pBtn_style_clicked();

    void on_pBtn_Fontcolor_clicked();

    void on_pBtn_setFont_clicked();

    void on_chk_scaleIsVisible_clicked(bool checked);

    void on_chk_gridLineVisible_clicked(bool checked);

    void on_pBtn_Fontcolor_2_clicked();

    void on_pBtn_Fontcolor_3_clicked();

    void on_spinBox_Tickcount_valueChanged(int arg1);

    void on_spinBox_minorTickcount_valueChanged(int arg1);

    void on_chk_TickLineIsVisible_clicked(bool checked);

    void on_pBtn_Fontcolor_5_clicked();

    void on_pBtn_Fontcolor_4_clicked();

    void on_pBtn_Fontcolor_7_clicked();

    void on_pBtn_Fontcolor_6_clicked();

    void on_chk_MinorTickLineIsVisible_clicked(bool checked);

private:
    Ui::MainWindow *ui;
    void createChart();
    QLineSeries* curSeries;
    QValueAxis* curAxis;

    void prepareData();
    void updateFromChart();
};
#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "ui_dialogPen.h"

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    createChart();
    prepareData();
    updateFromChart();
}

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

void MainWindow::on_actZoomOut_triggered()
{
    ui->cView->chart()->zoom(0.8);

}

void MainWindow::on_actZoomIn_triggered()
{
    ui->cView->chart()->zoom(1.2);
}

void MainWindow::on_actReset_triggered()
{
    ui->cView->chart()->zoomReset();
}

void MainWindow::createChart()
{
    QChart* chart = new QChart();
    chart->setTitle("simple curve");
    ui->cView->setChart(chart);
    ui->cView->setRenderHint(QPainter::Antialiasing);
    QLineSeries* series0 = new QLineSeries;
    QLineSeries* series1 = new QLineSeries;
    series0->setName("sin");
    series1->setName("cos");
    curSeries = series0;

    QPen pen;
    pen.setStyle(Qt::DotLine);
    pen.setWidth(2);
    series0->setPen(pen);
    pen.setStyle(Qt::SolidLine);
    pen.setColor(Qt::blue);
    series1->setPen(pen);

    chart->addSeries(series0);
    chart->addSeries(series1);

    QValueAxis* axisX = new QValueAxis;
    QValueAxis* axisY = new QValueAxis;
    curAxis = axisX;
    axisX->setRange(0,10);
    axisX->setLabelFormat("%.1f");
    axisX->setTickCount(11);
    axisX->setMinorTickCount(4);
    axisX->setTitleText("time(secs)");

    axisY->setRange(-1.5,1.5);
    axisY->setTickCount(3);
    axisY->setMinorTickCount(4);
    axisY->setTitleText("value");

    chart->setAxisX(axisX,series0);
    chart->setAxisX(axisX,series1);
    chart->setAxisY(axisY,series0);
    chart->setAxisY(axisY,series1);

}

void MainWindow::prepareData()
{
    QLineSeries* series0 = (QLineSeries*)ui->cView->chart()->series().at(0);
    QLineSeries* series1 = (QLineSeries*)ui->cView->chart()->series().at(1);
    int cnt = 100;
    series0->clear();
    series1->clear();
    qsrand(QTime::currentTime().second());
    qreal t=0, y1, y2, inv=0.1;
    qreal rd;
    for (int i=0; i<cnt; i++) {
        rd = (qrand()%10)-5;
        y1 = qSin(t) + rd/50;
        series0->append(t,y1);

        y2 = qCos(t) + rd/50;
        series1->append(t,y2);
        t += inv;
    }
}

void MainWindow::updateFromChart()
{
    QChart* chart = ui->cView->chart();
    ui->lineEdit_title->setText(chart->title());
    QMargins mg = chart->margins();
    ui->spinBox_Down->setValue(mg.bottom());
    ui->spinBox_Left->setValue(mg.left());
    ui->spinBox_Right->setValue(mg.right());
    ui->spinBox_Up->setValue(mg.top());
}

void MainWindow::on_actFlush_triggered()
{
    prepareData();
}

void MainWindow::on_btn_set_clicked()
{
    QChart *chart = ui->cView->chart();
    chart->setTitle(ui->lineEdit_title->text());
}

void MainWindow::on_btn_titleFont_clicked()
{
    QFont font = ui->cView->chart()->titleFont();
    bool ok = false;
    font = QFontDialog::getFont(&ok,font);
    if(ok)
        ui->cView->chart()->setTitleFont(font);
}

void MainWindow::on_rBtn_Up_clicked()
{
    ui->cView->chart()->legend()->setAlignment(Qt::AlignTop);
}

void MainWindow::on_rBtn_Down_clicked()
{
    ui->cView->chart()->legend()->setAlignment(Qt::AlignBottom);
}

void MainWindow::on_rBtn_Left_clicked()
{
    ui->cView->chart()->legend()->setAlignment(Qt::AlignLeft);
}

void MainWindow::on_rBtn_Right_clicked()
{
    ui->cView->chart()->legend()->setAlignment(Qt::AlignRight);
}

void MainWindow::on_checkBox_legend_clicked(bool checked)
{
    ui->cView->chart()->legend()->setVisible(checked);
}

void MainWindow::on_checkBox_legendBG_clicked(bool checked)
{
    ui->cView->chart()->legend()->setBackgroundVisible(checked);
}

void MainWindow::on_pBtn_Font_clicked()
{
    QFont font = ui->cView->chart()->legend()->font();
    bool ok = false;
    font = QFontDialog::getFont(&ok,font);
    if(ok)
        ui->cView->chart()->legend()->setFont(font);
}

void MainWindow::on_pBtn_legendcolor_clicked()
{
    QColor color = ui->cView->chart()->legend()->labelColor();
    color = QColorDialog::getColor(color);
    if(color.isValid())
        ui->cView->chart()->legend()->setLabelColor(color);
}

void MainWindow::on_pBtn_setMargin_clicked()
{
    QMargins mgs;
    mgs.setTop(ui->spinBox_Up->value());
    mgs.setLeft(ui->spinBox_Down->value());
    mgs.setLeft(ui->spinBox_Left->value());
    mgs.setRight(ui->spinBox_Right->value());
    ui->cView->chart()->setMargins(mgs);
}

void MainWindow::on_comboBox_motion_currentIndexChanged(int index)
{
    ui->cView->chart()->setAnimationOptions((QChart::AnimationOption)index);
}

void MainWindow::on_comboBox_theme_currentIndexChanged(int index)
{
    ui->cView->chart()->setTheme((QChart::ChartTheme)index);
}

void MainWindow::on_sin_curve_clicked()
{
    if(ui->sin_curve->isChecked())
        curSeries = (QLineSeries*)ui->cView->chart()->series().at(0);
    else
        curSeries = (QLineSeries*)ui->cView->chart()->series().at(1);

    //获取curSeries的值, 设置（标题名称，序列可见的，点数据可见，透明度滑动条）
    ui->lineEdit_title->setText(curSeries->name());
    ui->checkBox_curve->setChecked(curSeries->isVisible());
    ui->checkBox_data->setChecked(curSeries->pointsVisible());
    ui->horizontalSlider->setValue(curSeries->opacity()*10);
    ui->checkBox_pointLableVisible->setChecked(curSeries->pointLabelsVisible());
}

void MainWindow::on_cos_curve_clicked()
{
    on_sin_curve_clicked();
}

void MainWindow::on_pBtn_name_clicked()
{
    curSeries->setName(ui->line_name->text());
}

void MainWindow::on_checkBox_curve_clicked(bool checked)
{
    Q_UNUSED(checked)
    curSeries->setVisible(ui->checkBox_curve->isChecked());
}

void MainWindow::on_checkBox_data_clicked(bool checked)
{
    Q_UNUSED(checked)
    curSeries->setPointsVisible(ui->checkBox_data->isChecked());
}

void MainWindow::on_pBtn_color_clicked()
{
    QColor color = curSeries->color();
    color = QColorDialog::getColor(color);
    if(color.isValid())
        curSeries->setColor(color);
}

void MainWindow::on_pBtn_pen_clicked()
{
    bool ok = false;
    QPen pen = curSeries->pen();
    pen = DialogPen::getPen(pen, ok);
    if(ok)
        curSeries->setPen(pen);
}

void MainWindow::on_horizontalSlider_valueChanged(int value)
{
    curSeries->setOpacity(value/10.0);
}

void MainWindow::on_checkBox_pointLableVisible_clicked(bool checked)
{
    curSeries->setPointLabelsVisible(checked);
}

void MainWindow::on_pushButton_13_clicked()
{
    QColor color = curSeries->pointLabelsColor();
    color = QColorDialog::getColor(color);
    if(color.isValid())
        curSeries->setPointLabelsColor(color);
}

void MainWindow::on_pushButton_12_clicked()
{
    QFont font = curSeries->pointLabelsFont();
    bool ok = false;
    font = QFontDialog::getFont(&ok, font);
    if(ok)
        curSeries->setPointLabelsFont(font);
}

void MainWindow::on_rBtn_Y_clicked()
{
    if(ui->rBtn_Y->isChecked())
        curSeries->setPointLabelsFormat("@yPoint");
    else
        curSeries->setPointLabelsFormat("(@xPoint,@yPoint)");
}

void MainWindow::on_rBtn_XY_clicked()
{
    on_rBtn_Y_clicked();
}

void MainWindow::on_rBtn_XAxies_clicked()
{
    // 设置坐标轴
    QList<QAbstractAxis*> axes;
    if(ui->rBtn_XAxies->isChecked())
        axes = ui->cView->chart()->axes(Qt::Horizontal);
    else
        axes = ui->cView->chart()->axes(Qt::Vertical);
    curAxis = (QValueAxis*)axes[0];

    //获取坐标轴属性，显示到界面上
    ui->dSBox_minV->setValue(curAxis->min());
    ui->dSBox_maxV->setValue(curAxis->max());

    ui->Axis_title->setText(curAxis->titleText());
    ui->Axis_titleIsVisible->setChecked(curAxis->isTitleVisible());

    ui->lineEdit_style->setText(curAxis->labelFormat());
    ui->chk_scaleIsVisible->setChecked(curAxis->labelsVisible());

    ui->chk_gridLineVisible->setChecked(curAxis->isGridLineVisible());

    ui->spinBox_Tickcount->setValue(curAxis->tickCount());
    ui->chk_TickLineIsVisible->setChecked(curAxis->isLineVisible());

    ui->spinBox_minorTickcount->setValue(curAxis->minorTickCount());
    ui->chk_MinorTickLineIsVisible->setChecked(curAxis->isMinorGridLineVisible());

}

void MainWindow::on_rBtn_YAxies_clicked()
{
    on_rBtn_XAxies_clicked();
}

void MainWindow::on_Axis_isVisible_clicked(bool checked)
{
    curAxis->setVisible(checked);
}

void MainWindow::on_Axis_range_clicked()
{
    curAxis->setRange(ui->dSBox_minV->value(), ui->dSBox_maxV->value());
}

void MainWindow::on_Axis_setTitle_clicked()
{
    curAxis->setTitleText(ui->Axis_title->text());
}

void MainWindow::on_Axis_titleIsVisible_clicked(bool checked)
{
    curAxis->setTitleVisible(checked);
}

void MainWindow::on_pBtn_style_clicked()
{
    curAxis->setLabelFormat(ui->lineEdit_style->text());
}

void MainWindow::on_pBtn_Fontcolor_clicked()
{
    QColor color = curAxis->labelsColor();
    color = QColorDialog::getColor(color);
    if(color.isValid())
        curAxis->setLabelsColor(color);
}

void MainWindow::on_pBtn_setFont_clicked()
{
    QFont font = curAxis->labelsFont();
    bool ok = false;
    font = QFontDialog::getFont(&ok, font);
    if(ok)
        curAxis->setLabelsFont(font);
}

void MainWindow::on_chk_scaleIsVisible_clicked(bool checked)
{
    curAxis->setLineVisible(checked);
}

void MainWindow::on_chk_gridLineVisible_clicked(bool checked)
{
    curAxis->setGridLineVisible(checked);
}

void MainWindow::on_pBtn_Fontcolor_2_clicked()
{
    QColor color = curAxis->gridLineColor();
    color = QColorDialog::getColor(color);
    if(color.isValid())
        curAxis->setGridLineColor(color);
}

void MainWindow::on_pBtn_Fontcolor_3_clicked()
{
    bool ok = false;
    QPen pen = curAxis->gridLinePen();
    pen = DialogPen::getPen(pen, ok);
    if(ok)
        curAxis->setGridLinePen(pen);
}

void MainWindow::on_spinBox_Tickcount_valueChanged(int arg1)
{
    curAxis->setTickCount(arg1);
}

void MainWindow::on_spinBox_minorTickcount_valueChanged(int arg1)
{
    curAxis->setMinorTickCount(arg1);
}

void MainWindow::on_chk_TickLineIsVisible_clicked(bool checked)
{
    curAxis->setLineVisible(checked);
}

void MainWindow::on_pBtn_Fontcolor_5_clicked()
{
    bool ok = false;
    QPen pen = curAxis->linePen();
    pen = DialogPen::getPen(pen, ok);
    if(ok)
        curAxis->setLinePen(pen);
}

void MainWindow::on_pBtn_Fontcolor_4_clicked()
{
    QColor color = curAxis->linePenColor();
    color = QColorDialog::getColor(color);
    if(color.isValid())
        curAxis->setLinePenColor(color);
}

void MainWindow::on_pBtn_Fontcolor_7_clicked()
{
    QColor color = curAxis->minorGridLineColor();
    color = QColorDialog::getColor(color);
    if(color.isValid())
        curAxis->setMinorGridLineColor(color);
}

void MainWindow::on_pBtn_Fontcolor_6_clicked()
{
    bool ok = false;
    QPen pen = curAxis->gridLinePen();
    pen = DialogPen::getPen(pen, ok);
    if(ok)
        curAxis->setGridLinePen(pen);
}

void MainWindow::on_chk_MinorTickLineIsVisible_clicked(bool checked)
{
    curAxis->setMinorGridLineVisible(checked);
}

效果演示

到此这篇关于QT中QChart绘制折线图的文章就介绍到这了,更多相关QChart绘制折线图内容请搜索我们以前的文章或继续浏览下面的相关文章希望大家以后多多支持我们！