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29 ** GNU General Public License Usage
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49 // This file is not part of the Qt API. It exists for the convenience
50 // of qapplication_*.cpp, qwidget*.cpp and qfiledialog.cpp. This header
51 // file may change from version to version without notice, or even be removed.
56 #include <QtCore/qglobal.h>
57 #include <QtCore/qvariant.h>
58 #include <private/qqmldata_p.h>
65 inline QQmlGuardImpl();
66 inline QQmlGuardImpl(QObject *);
67 inline QQmlGuardImpl(const QQmlGuardImpl &);
68 inline ~QQmlGuardImpl();
74 inline void addGuard();
75 inline void remGuard();
80 class QQmlGuard : private QQmlGuardImpl
82 friend class QQmlData;
85 inline QQmlGuard(T *);
86 inline QQmlGuard(const QQmlGuard<T> &);
87 inline virtual ~QQmlGuard();
89 inline QQmlGuard<T> &operator=(const QQmlGuard<T> &o);
90 inline QQmlGuard<T> &operator=(T *);
92 inline T *object() const;
93 inline void setObject(T *g);
95 inline bool isNull() const
98 inline T* operator->() const
99 { return static_cast<T*>(const_cast<QObject*>(o)); }
100 inline T& operator*() const
101 { return *static_cast<T*>(const_cast<QObject*>(o)); }
102 inline operator T*() const
103 { return static_cast<T*>(const_cast<QObject*>(o)); }
104 inline T* data() const
105 { return static_cast<T*>(const_cast<QObject*>(o)); }
108 virtual void objectDestroyed(T *) {}
113 Q_DECLARE_METATYPE(QQmlGuard<QObject>)
117 QQmlGuardImpl::QQmlGuardImpl()
118 : o(0), next(0), prev(0)
122 QQmlGuardImpl::QQmlGuardImpl(QObject *g)
123 : o(g), next(0), prev(0)
128 QQmlGuardImpl::QQmlGuardImpl(const QQmlGuardImpl &g)
129 : o(g.o), next(0), prev(0)
134 QQmlGuardImpl::~QQmlGuardImpl()
136 if (prev) remGuard();
140 void QQmlGuardImpl::addGuard()
144 if (QObjectPrivate::get(o)->wasDeleted)
147 QQmlData *data = QQmlData::get(o, true);
149 if (next) next->prev = &next;
151 prev = &data->guards;
154 void QQmlGuardImpl::remGuard()
158 if (next) next->prev = prev;
165 QQmlGuard<T>::QQmlGuard()
170 QQmlGuard<T>::QQmlGuard(T *g)
176 QQmlGuard<T>::QQmlGuard(const QQmlGuard<T> &g)
182 QQmlGuard<T>::~QQmlGuard()
187 QQmlGuard<T> &QQmlGuard<T>::operator=(const QQmlGuard<T> &g)
189 setObject(g.object());
194 QQmlGuard<T> &QQmlGuard<T>::operator=(T *g)
201 T *QQmlGuard<T>::object() const
203 return static_cast<T *>(o);
207 void QQmlGuard<T>::setObject(T *g)
210 if (prev) remGuard();
218 #endif // QQMLGUARD_P_H