For a NOTIFY signal on a property, what's the difference if I give it a parameter?

Question

Suppose I have a class that looks like this:

class Something : QObject {
  Q_PROPERTY(int something READ getSomething NOTIFY somethingChanged)

  // ...

  signals:
    void somethingChanged();
}

According to the documentation, announcements somethingChangedlike void somethingChanged(), and void somethingChanged(int)(pay attention to the option) are valid. Why do I want to do this one by one?

Answer 1

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