单选按钮永远不会出现

Question

使用以下代码在组框中创建单选按钮，没有任何结果。有点背景：在我的显示中，每个对象都有多个变体，用户必须选择要显示哪个（或全部）。我错过了什么更新/刷新命令，或者出了什么问题？

for(int i = 0; i < MAX_NUM_VARIANTS+1; i++)
    {
        m_variantButtons[i] = new QRadioButton();
        m_variantButtons[i]->setText(QString::number(i));
        m_variantButtons[i]->setObjectName(QString("m_pbDisplayVariant%1").arg(i));

        QSizePolicy sizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);
        sizePolicy.setHorizontalStretch(0);
        sizePolicy.setVerticalStretch(0);
        sizePolicy.setHeightForWidth(true);
        m_variantButtons[i]->setSizePolicy(sizePolicy);

        ((QGridLayout*)(ui.m_groupBoxVariants->layout()))->addWidget(m_variantButtons[i], 1, i);
        ((QGridLayout*)(ui.m_groupBoxVariants->layout()))->update();
        connect(m_variantButtons[i], SIGNAL(clicked(bool)), this, SLOT(updateDisplaySettings()));
        m_variantButtons[i]->setVisible(true);
    }
    ((QWidget*)(ui.m_groupBoxVariants))->updateGeometry();