添加画布相关的代码，对main.cpp添加以下的代码:

main.cpp

#include <Qt3DWindow>
#include <QForwardRenderer>
#include <QScreen>
#include <QHBoxLayout>
#include <QVBoxLayout>

int main()
{
        Qt3DExtras::Qt3DWindow *view = new Qt3DExtras::Qt3DWindow();
    view->defaultFrameGraph()->setClearColor(QColor(QRgb(0x81fdff)));
    //创建画布

    QWidget *container = QWidget::createWindowContainer(view);
    QSize screenSize = view->screen()->size();
    container->setMinimumSize(QSize(200, 100));
    container->setMaximumSize(screenSize);
    //创建画布的容器，并将画布作为参数放进容器 QWidget *container = QWidget::createWindowContainer(view);

    QHBoxLayout *hLayout = new QHBoxLayout(widget);
    QVBoxLayout *vLayout = new QVBoxLayout();
    vLayout->setAlignment(Qt::AlignTop);
    hLayout->addWidget(container, 1);
    hLayout->addLayout(vLayout);
    //将画布的容器container放到窗口对象widget中，并添加布局

    //至此 画布添加完毕
}

省略掉了上一篇中已经存在的代码，运行效果如下