您需要为 QToolTip 添加样式表.例如:

You need add style sheet for QToolTip. Ex.:

QString style = QString(
    "QPushButton {"
    // StyleSheet for your push button
    "    background: blue;"
    "}"
    "QToolTip {"
    // StyleSheet for tool tip
    "    background: red;"
    "}"
    );

this->cellGUI.status_label->setStyleSheet(style);