How could Qt apply style from an external Qt Stylesheet file?

Question

I would like the users to be able to customize the default look of our applications by simply loading their OWN Qt Style-sheet files. How do we accomplish that? Can anybody give me a head start?

Answer 1

Say the user have its stylesheet named stylesheet.qss and is located in the application folder.

You could load the style sheet when starting the application, using the -stylesheet argument :

myapp->stylesheet = stylesheet.qss; 

But this require your user to know how to start an application with arguments.

What you could also do is to add a settings dialog in your app, where the user can choose a stylesheet path.

You can then open this file, load the content, and set it to your application with QApplication::setStyleSheet() :

 QFile file("stylesheet.qss");  file.open(QFile::ReadOnly);  QString styleSheet = QLatin1String(file.readAll());   qApp->setStyleSheet(styleSheet); 

Qt is providing an example online which might be helpful.

Answer 2

You just set the style sheet for the entire application based on configuration provided by the customer.

http://doc.qt.io/qt-5/qapplication.html#styleSheet-prop

You could set/get this configuration from any number of places, a properties dialog in the application is probably the most natural approach.