QT 扇形图

　　 ui->widget->setStyleSheet("QWidget{background-color:#222648;}");
    series = new QPieSeries();
    series->append("20%", 2);
    series->append("50%", 5);
    series->append("30%", 3);
    series->setLabelsVisible();

    QPieSlice *slice_red = series->slices().at(0);　　//添加扇区
    QPieSlice *slice_green = series->slices().at(1);
    QPieSlice *slice_black = series->slices().at(2);
    slice_red->setColor(QColor(199,38,22));　　　　　　//设置颜色
    slice_green->setColor(QColor(0,165,94));
    slice_black->setColor(QColor(54,54,54));
    slice_red->setLabelColor(QColor(255,255,255));　　//设置label的颜色
    slice_green->setLabelColor(QColor(255,255,255));
    slice_black->setLabelColor(QColor(255,255,255));
    //slice_red->setExploded();//展开
    QFont font;
    font.setPointSize(9);　　　　//设置字体大小，如果字体过大容易显示不出来
    slice_red->setLabelFont(font);
    slice_green->setLabelFont(font);
    slice_black->setLabelFont(font);

    QChart *chart = new QChart();
    chart->addSeries(series);
    chart->legend()->hide();
    chart->setBackgroundBrush(QBrush(QColor(34,38,72)));
    chart->setAnimationOptions(QChart::AllAnimations);//设置启用或禁用动画

    QChartView *chartview = new QChartView(chart);
    chartview->setRenderHint(QPainter::Antialiasing);
    chartview->setParent(ui->widget);
    chartview->resize(ui->widget->size());

在使用时，需要在pro文件里面添加一行代码

QT += charts