饼状图二

 参考资料：

https://blog.csdn.net/lmhuanying1012/article/details/78454608

效果图：

     QPieSeries *series = new QPieSeries();

     //series->setHoleSize(0.35);

     series->append("10%", 1);

     series->append("20%", 2);

     series->append("70%", 7);

     series->setLabelsVisible();

     QPieSlice *slice_red = series->slices().at(0);

     QPieSlice *slice_green = series->slices().at(1);

     QPieSlice *slice_blue = series->slices().at(2);

     slice_red->setColor(QColor(255,0,0,255));

     slice_green->setColor(QColor(0,255,0,255));

     slice_blue->setColor(QColor(0,0,255,255));

     QChart *chart = new QChart();

     chart->addSeries(series);

     chart->setTitle("PieChart Example");

     chart->legend()->hide();

     QChartView *chartview = new QChartView(chart);

     chartview->setRenderHint(QPainter::Antialiasing);

     chartview->chart()->setTheme(QChart::ChartThemeBlueCerulean);

     chartview->chart()->legend()->setFont(QFont("Arial", 7));

     QVBoxLayout *vb = new QVBoxLayout(this);

     vb->addWidget(chartview);

     this->setLayout(vb);