Qt：绘制折线图时图标以及坐标轴设置

曾经终败给现在 2023-01-12 11:44 675阅读 0赞

1、创建QT GUI应用，基类选择"QMainWindows"，在.pro中添加：

QT       += charts

在源文件中添加：

#include  <QtCharts>

2、在构造函数中添加：

QChartView *chartView = new QChartView(this);

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QChartView *chartView = new QChartView(this);
    
        QChart *chart = new QChart();
        chart->setTitle("简单函数曲线");   //图标的名字
        chartView->setChart(chart);
        setCentralWidget(chartView);
    
        //创建曲线序列
        QLineSeries *series0 = new QLineSeries();
        QLineSeries *series1 = new QLineSeries();
        series0->setName("sin曲线");   //自动添加折线名字
        series1->setName("cos曲线");
        chart->addSeries(series0);
        chart->addSeries(series1);
    
        //序列添加数值
        qreal t = 0, y1, y2, intv = 0.1;
        int cnt = 200;
        for(int i = 0; i < cnt; ++i){
            y1 = qSin(t);
            series0->append(t, y1);
    
            y2=qSin(t+20);
            series1->append(t,y2);
    
            t+=intv;  //每次角度增加
        }
    
        //创建坐标
        QValueAxis *axisX = new QValueAxis;
        axisX->setRange(0, 10);//设置坐标轴范围
        axisX->setTitleText("time(secs)");//标题
        axisX->setLabelFormat("%.1f"); //标签格式：每个单位保留几位小数
        axisX->setTickCount(20); //主分隔个数：0到10分成20个单位
        axisX->setMinorTickCount(4); //每个单位之间绘制了多少虚网线
    //    axisX->setGridLineVisible(false);
    
        QValueAxis *axisY = new QValueAxis; //Y 轴
        axisY->setRange(-2, 2);
        axisY->setTitleText("value");
        axisY->setLabelFormat("%.2f"); //标签格式
        axisY->setTickCount(10);
        axisY->setMinorTickCount(4);
    //    axisX->setGridLineVisible(false);
    
        //为序列设置坐标轴
        chart->setAxisX(axisX, series0);
        chart->setAxisY(axisY, series0);
    
        chart->setAxisX(axisX, series1);
        chart->setAxisY(axisY, series1);

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[39264c889751231ff527a8d4c09c3d6a7c1.jpg]: /images/20221119/c4e78989dae046f6a074d76b042f991c.png
[c1182781dcacd34b79f2f758f3803b4edd2.jpg]: /images/20221119/5e3eff421b554a7fa4edef51e321f400.png
[bcddf5cfa370841b1dbbe71f9dba03d5b2e.jpg]: /images/20221119/a328396b6a7e4fbcb9127d3d1fde50af.png
[b1ef5bf5b1b8bf49fb0cf7708e14976135a.jpg]: /images/20221119/94d87ea773084162b11d3f190e1bc5dc.png