Why does changing a QML property from C++ fail?

QM • Qt Forum member • September 11, 2026 • 1 answers

A Qt Forum user attempted to find a QML object from C++ and change its color property, but the change did not occur.

cpp

obj->setProperty("color", "blue");

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1 Answer

Dheerendra V Purohit

September 11, 2026 • Independent answer

✓ Accepted

Dheerendra advised checking both the object being found and the return value of setProperty(). The loaded object must actually expose the requested property, and the located object must not be null.

cpp

if (!obj || !obj->setProperty("color", "blue")) {    qWarning() << "Failed to set the color property";}

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