QPalette pal = QWidget::palette(); pal.setColor(QPalette::Background, Qt::red); QWidget::setPalette(pal);
QSpinBox* spinBox = new QSpinBox(); QPalette pal = spinBox->palette(); pal.setColor(QPalette::Text, Qt::blue); spinBox->setPalette(pal);
QGroupBox* groupBox = new QGroupBox(); QPalette pal = groupBox->palette(); pal.setColor(QPalette::Background, Qt::yellow); groupBox->setPalette(pal); QLabel* label = new QLabel("Example label", groupBox); QPalette labelPal = label->palette(); labelPal.setColor(QPalette::Background, Qt::green); label->setPalette(labelPal);This code creates a new QGroupBox object and sets its background color to yellow. It then creates a new QLabel object and adds it as a child of the group box. Finally, it sets the background color of the label to green. The package library for the QWidget palette is the Qt library, which is a widely-used C++ toolkit for building graphical user interfaces.