Readonly Property
Cannot Assign To Read-Only Property
What happened?
A read-only property was written.
Why is this bad?
The QML engine will throw a Type Error when it sees the write to a read-only property.
Example
import QtQuick Item { id: root readonly property int someNumber: 10 Component.onCompleted: { someNumber = 20 // not ok: TypeError: Cannot assign to read-only property } }
You can fix this warning by removing the write to the read-only property, by writing to another non-read-only property, or by removing the readonly modifier if the property should no longer be considered constant.
See also Read-Only Properties.