QLineEdit QSpinBox QDoubleSpinBox can not change background color 不能设置背景色彩

code :

QLineEdit *nameEdit = new QLineEdit(this);

nameEdit->setGeometry(30,50,350,50);

nameEdit->setText("QLineEdit can not change background color");

nameEdit->setStyleSheet(// "QLineEdit { background-color: rgb(255, 0, 0) }" "color: blue;" "background-color: yellow;" "alternate-background-color: blue;" "selection-color: yellow;" "selection-background-color: blue;" );