C++ is one of the main langauges that can be used to write a Cascades app (QML being the other).  It can be the only language used in your application, meaning you can define all of your user interface (UI) and logic (using signal/slots). However this site doesn't focus on using C++ for the UI, rather that will be handled with QML.  How this site does use C++ is to handle logic that cannot be handled using JavaScript.  In the cases where QML is used to initiate the C++ function, you need to set up a "context property" in your .cpp file to expose the C++ to the QML (see "Running C++ Function from QML" example for a more complete overview).

Examples/Tutorials Using This Feature:

Running C++ Function from QML (Trivial Example)

Persistence of Cascades Memory

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