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39
40#ifndef QPOINTER_H
41#define QPOINTER_H
42
43#include <QtCore/qsharedpointer.h>
44#include <QtCore/qtypeinfo.h>
45
46#ifndef QT_NO_QOBJECT
47
48QT_BEGIN_NAMESPACE
49
50class QVariant;
51
52template <class T>
53class QPointer
54{
55 Q_STATIC_ASSERT_X(!std::is_pointer<T>::value, "QPointer's template type must not be a pointer type");
56
57 using QObjectType =
58 typename std::conditional<std::is_const<T>::value, const QObject, QObject>::type;
59 QWeakPointer<QObjectType> wp;
60public:
61 QPointer() = default;
62 inline QPointer(T *p) : wp(p, true) { }
63 // compiler-generated copy/move ctor/assignment operators are fine!
64 // compiler-generated dtor is fine!
65
66#ifdef Q_QDOC
67 // Stop qdoc from complaining about missing function
68 ~QPointer();
69#endif
70
71 inline void swap(QPointer &other) noexcept { wp.swap(other.wp); }
72
73 inline QPointer<T> &operator=(T* p)
74 { wp.assign(static_cast<QObjectType*>(p)); return *this; }
75
76 inline T* data() const
77 { return static_cast<T*>(wp.internalData()); }
78 inline T* operator->() const
79 { return data(); }
80 inline T& operator*() const
81 { return *data(); }
82 inline operator T*() const
83 { return data(); }
84
85 inline bool isNull() const
86 { return wp.isNull(); }
87
88 inline void clear()
89 { wp.clear(); }
90};
91template <class T> Q_DECLARE_TYPEINFO_BODY(QPointer<T>, Q_MOVABLE_TYPE);
92
93template <class T>
94inline bool operator==(const T *o, const QPointer<T> &p)
95{ return o == p.operator->(); }
96
97template<class T>
98inline bool operator==(const QPointer<T> &p, const T *o)
99{ return p.operator->() == o; }
100
101template <class T>
102inline bool operator==(T *o, const QPointer<T> &p)
103{ return o == p.operator->(); }
104
105template<class T>
106inline bool operator==(const QPointer<T> &p, T *o)
107{ return p.operator->() == o; }
108
109template<class T>
110inline bool operator==(const QPointer<T> &p1, const QPointer<T> &p2)
111{ return p1.operator->() == p2.operator->(); }
112
113template <class T>
114inline bool operator!=(const T *o, const QPointer<T> &p)
115{ return o != p.operator->(); }
116
117template<class T>
118inline bool operator!= (const QPointer<T> &p, const T *o)
119{ return p.operator->() != o; }
120
121template <class T>
122inline bool operator!=(T *o, const QPointer<T> &p)
123{ return o != p.operator->(); }
124
125template<class T>
126inline bool operator!= (const QPointer<T> &p, T *o)
127{ return p.operator->() != o; }
128
129template<class T>
130inline bool operator!= (const QPointer<T> &p1, const QPointer<T> &p2)
131{ return p1.operator->() != p2.operator->() ; }
132
133template<typename T>
134QPointer<T>
135qPointerFromVariant(const QVariant &variant)
136{
137 const auto wp = QtSharedPointer::weakPointerFromVariant_internal(variant);
138 return QPointer<T>{qobject_cast<T*>(QtPrivate::EnableInternalData::internalData(p: wp))};
139}
140
141template <class T>
142inline void swap(QPointer<T> &p1, QPointer<T> &p2) noexcept
143{ p1.swap(p2); }
144
145QT_END_NAMESPACE
146
147#endif // QT_NO_QOBJECT
148
149#endif // QPOINTER_H
150

source code of qtbase/src/corelib/kernel/qpointer.h