The QtDeclarative module provides a set of APIs for extending QML through C++ extensions. You can write extensions to add your own QML types, extend existing Qt types, or call C/C++ functions that are not accessible from ordinary QML code.
This tutorial shows how to write a QML extension using C++ that includes core QML features, including properties, signals and bindings. It also shows how extensions can be deployed through plugins.
You can find the source code for this tutorial in Qt's examples/declarative/tutorials/extending directory.
Tutorial chapters: