Behaviour of a c++ model update from a different thread from which the QML QtQuick2 engine is running

[A Former User]

The scenario has following components:

• C++ QAbstractItemModel derived model class created in main thread
• QML QtQuick2 Engine instantiated in main thread
• Worker boost::thread spawned from main thread upon user interaction

The relations between these components:

• The C++ model is exposed through a Q_PROPERTY of a type registered with qmlRegisterSingletonType<>() to the QML Engine.
• The worker thread updates the model through a method that invokes "emit data_changed(...)"

The question: in which thread does the callback of the "emit data_changed(...)" happen?

Note

A key element in this question is that the started thread is not qt aware.

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