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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
48 QT_BEGIN_NAMESPACE
49
50 class QVariant;
51
52 template <class T>
53 class 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;
60 public:
61 QPointer() = default;
QPointer(T * p)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
swap(QPointer & other)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
data()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
isNull()85 inline bool isNull() const
86 { return wp.isNull(); }
87
clear()88 inline void clear()
89 { wp.clear(); }
90 };
91 template <class T> Q_DECLARE_TYPEINFO_BODY(QPointer<T>, Q_MOVABLE_TYPE);
92
93 template <class T>
94 inline bool operator==(const T *o, const QPointer<T> &p)
95 { return o == p.operator->(); }
96
97 template<class T>
98 inline bool operator==(const QPointer<T> &p, const T *o)
99 { return p.operator->() == o; }
100
101 template <class T>
102 inline bool operator==(T *o, const QPointer<T> &p)
103 { return o == p.operator->(); }
104
105 template<class T>
106 inline bool operator==(const QPointer<T> &p, T *o)
107 { return p.operator->() == o; }
108
109 template<class T>
110 inline bool operator==(const QPointer<T> &p1, const QPointer<T> &p2)
111 { return p1.operator->() == p2.operator->(); }
112
113 template <class T>
114 inline bool operator!=(const T *o, const QPointer<T> &p)
115 { return o != p.operator->(); }
116
117 template<class T>
118 inline bool operator!= (const QPointer<T> &p, const T *o)
119 { return p.operator->() != o; }
120
121 template <class T>
122 inline bool operator!=(T *o, const QPointer<T> &p)
123 { return o != p.operator->(); }
124
125 template<class T>
126 inline bool operator!= (const QPointer<T> &p, T *o)
127 { return p.operator->() != o; }
128
129 template<class T>
130 inline bool operator!= (const QPointer<T> &p1, const QPointer<T> &p2)
131 { return p1.operator->() != p2.operator->() ; }
132
133 template<typename T>
134 QPointer<T>
qPointerFromVariant(const QVariant & variant)135 qPointerFromVariant(const QVariant &variant)
136 {
137 const auto wp = QtSharedPointer::weakPointerFromVariant_internal(variant);
138 return QPointer<T>{qobject_cast<T*>(QtPrivate::EnableInternalData::internalData(wp))};
139 }
140
141 template <class T>
swap(QPointer<T> & p1,QPointer<T> & p2)142 inline void swap(QPointer<T> &p1, QPointer<T> &p2) noexcept
143 { p1.swap(p2); }
144
145 QT_END_NAMESPACE
146
147 #endif // QT_NO_QOBJECT
148
149 #endif // QPOINTER_H
150