how to declare global (static?) function inside class?

[mzimmers]

Hi all -

I have a class with a member function that I'd like to use without having to instantiate an object of the class. I've never done this before, but this is what I tried:

#pragma once

#include <QObject>
#include <QQmlEngine>

class Clock : public QObject
{
    Q_OBJECT
    QML_ELEMENT
public:
    explicit Clock(QObject *parent = nullptr);

    static bool m_use24hourTime;
    static QString getTimeString(QTime time);
}
};

I get a link error:

undefined reference to `Clock::m_use24hourTime'

so I'm obviously doing something wrong. I do use that variable in other routines in the class.

Can someone tell me what I'm doing wrong here?

Thanks...

[Christian Ehrlicher]

@mzimmers said in how to declare global (static?) function inside class?:

so I'm obviously doing something wrong

You just declare the variable but don't define them anywhere.

[mzimmers]

Aargh...forgot all about that. Thanks!

[JoeCFD]

@mzimmers inline might be more convenient. No need to define it in cpp file.

inline static bool m_use24hourTime{ false };