In the context of the Qt framework, QSS stands for Qt Style Sheets, which is a feature that allows users to apply custom styles to the user interface of a Qt application. Qt Style Sheets are written in a special syntax that is based on CSS (Cascading Style Sheets), and they can be used to change the appearance of widgets, layouts, and other elements of a user interface.
Qt Style Sheets provide a convenient and powerful way for users to customize the look and feel of their Qt applications, without having to write complex code. For example, a QSS file could be used to change the default font and colors used in a Qt application, or to modify the layout and spacing of widgets in a user interface.
Overall, the main function of QSS in Qt is to allow users to easily customize the appearance of their applications, using a simple and intuitive styling language.
To apply this QSS to a widget, you would first create a QString variable containing the QSS code, and then pass that string to the QWidget's setStyleSheet() method.
For example :
QString qss = "QTabWidget { background-color: white; } ..."; // QSS code as shown above
QTabWidget* tabWidget = new QTabWidget;
tabWidget->setStyleSheet(qss);
This would apply the custom styles to the QTabWidget, resulting in a user interface with the appearance specified by the QSS code. Note that you can use the QSS style property to apply these styles to specific instances of QTabWidget, rather than applying them globally to all instances of the widget.