@sierdzio as knowledgeable users, I believe we shouldn't foster beginners' bad practices but bring them back in the right track.

How should I know if it is a beginner? I've seen something like this used to do real magic in a project, and my tough experts.

In general, yes you're right, it is not "the way" to do things in QML projects. But it's not forbidden, and maybe could be useful in some certain edge cases.

Also you should not modify your QML object from c++.

https://doc.qt.io/qt-5/qtquick-bestpractices.html#interacting-with-qml-from-c
http://doc.qt.io/qt-5/qtqml-cppintegration-overview.html#interacting-with-qml-objects-from-c
https://youtu.be/vzs5VPTf4QQ?t=23m20s

@sierdzio as knowledgeable users, I believe we shouldn't foster beginners' bad practices but bring them back in the right track.

@LISP expose a QObject subclass with a QString Q_PROPERTY and bind to that in your objectText object from QML.
When you want to change the text, change the property and emit its notify signal and the QML side will get automatically updated.

Thank you sir!
text.setProperty("text", "Change");
This is the first method I've used, but still no response.
Will others be updated right away?

QQmlProperty::write(text, "text", QVariant("Change"));

Use QObject instead:

text.setProperty("text", "Change");