dsingleton.h

// SPDX-FileCopyrightText: 2016 - 2022 UnionTech Software Technology Co., Ltd.
//
// SPDX-License-Identifier: LGPL-3.0-or-later
 
#ifndef DSINGLETON_H
#define DSINGLETON_H
 
#include "dtkcore_global.h"
 
DCORE_BEGIN_NAMESPACE
 
template <class T>
class LIBDTKCORESHARED_EXPORT DSingleton
{
public:
#if DTK_VERSION < DTK_VERSION_CHECK(6, 0, 0, 0)
    QT_DEPRECATED_X("Use ref")
    static inline T *instance()
    {
        static T  *_instance = new T;
        return _instance;
    }
#endif
    static T& ref()
    {
        static T instance;
        return instance;
    }
 
    DSingleton(T&&) = delete;
    DSingleton(const T&) = delete;
    void operator= (const T&) = delete;
 
protected:
    DSingleton() = default;
    virtual ~DSingleton() = default;
};
 
DCORE_END_NAMESPACE
 
#endif // DSINGLETON_H