[提问]菜鸟求助：qt 5.4节问题 [复制链接]

目的，想利用5.4节的plotter类进行动态画图，可是结果不是预想的。修改部分的代码如下：
   // int numPoints = 100;    QVector<QPointF> points0;  //  QVector<QPointF> points1;   /* for (int x = 0; x < numPoints; ++x) {        points0.append(QPointF(x, uint(qrand()) % 100));        points1.append(QPointF(x, uint(qrand()) % 100));    }*/    points0.append(QPointF(3, 8));    points0.append(QPointF(4, 18));    plotter.setCurveData(0, points0);    plotter.show();    QTest::qSleep(5000);    points0.append(QPointF(4, 8));    plotter.setCurveData(0, points0);    plotter.show();     app.exec();可是show后面没有出现图，必须等到。exec才出现，请问有什么解决办法？
我想做的是从试验台不定时得到个数据，然后动态的画在图上……求助

   // int numPoints = 100;
    QVector<QPointF> points0;
  //  QVector<QPointF> points1;
   /* for (int x = 0; x < numPoints; ++x) {
        points0.append(QPointF(x, uint(qrand()) % 100));
        points1.append(QPointF(x, uint(qrand()) % 100));
    }*/
    points0.append(QPointF(3, 8));
    points0.append(QPointF(4, 18));
    plotter.setCurveData(0, points0);
    plotter.show();

    QTest::qSleep(5000);
    points0.append(QPointF(4, 8));
    plotter.setCurveData(0, points0);
    plotter.show();
     app.exec();