一、Q_DECLARE_PRIVATE(Class)

#define Q_DECLARE_PRIVATE(Class) inline Class##Private* d_func() { # 此处的 d_ptr 是属于QObject类中的私有成员变量Q_CAST_IGNORE_ALIGN(return reinterpret_cast<Class##Private *>(qGetPtrHelper(d_ptr));)           } inline const Class##Private* d_func() const { Q_CAST_IGNORE_ALIGN(return reinterpret_cast<const Class##Private *>(qGetPtrHelper(d_ptr));) } friend class Class##Private;

二、Q_DECLARE_PRIVATE_D(Dptr, Class)

#define Q_DECLARE_PRIVATE_D(Dptr, Class) inline Class##Private* d_func() {Q_CAST_IGNORE_ALIGN(return reinterpret_cast<Class##Private *>(qGetPtrHelper(Dptr));) } inline const Class##Private* d_func() const {Q_CAST_IGNORE_ALIGN(return reinterpret_cast<const Class##Private *>(qGetPtrHelper(Dptr));) } friend class Class##Private;

三、Q_DECLARE_PUBLIC(Class)

#define Q_DECLARE_PUBLIC(Class)                                    inline Class* q_func() {return static_cast<Class *>(q_ptr); } inline const Class* q_func() const{ return static_cast<const Class *>(q_ptr); } friend class Class;

四、Q_D(Class) 和 Q_Q(Class)

#define Q_D(Class) Class##Private * const d = d_func()
#define Q_Q(Class) Class * const q = q_func()