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50
51 //! [0]
myFunction(bool useSubClass)52 void myFunction(bool useSubClass)
53 {
54 MyClass *p = useSubClass ? new MyClass() : new MySubClass;
55 QIODevice *device = handsOverOwnership();
56
57 if (m_value > 3) {
58 delete p;
59 delete device;
60 return;
61 }
62
63 try {
64 process(device);
65 }
66 catch (...) {
67 delete p;
68 delete device;
69 throw;
70 }
71
72 delete p;
73 delete device;
74 }
75 //! [0]
76
77 //! [1]
myFunction(bool useSubClass)78 void myFunction(bool useSubClass)
79 {
80 // assuming that MyClass has a virtual destructor
81 QScopedPointer<MyClass> p(useSubClass ? new MyClass() : new MySubClass);
82 QScopedPointer<QIODevice> device(handsOverOwnership());
83
84 if (m_value > 3)
85 return;
86
87 process(device);
88 }
89 //! [1]
90
91 //! [2]
92 const QWidget *const p = new QWidget();
93 // is equivalent to:
94 const QScopedPointer<const QWidget> p(new QWidget());
95
96 QWidget *const p = new QWidget();
97 // is equivalent to:
98 const QScopedPointer<QWidget> p(new QWidget());
99
100 const QWidget *p = new QWidget();
101 // is equivalent to:
102 QScopedPointer<const QWidget> p(new QWidget());
103 //! [2]
104
105 //! [3]
106 if (scopedPointer) {
107 ...
108 }
109 //! [3]
110
111 //! [4]
112 class MyPrivateClass; // forward declare MyPrivateClass
113
114 class MyClass
115 {
116 private:
117 QScopedPointer<MyPrivateClass> privatePtr; // QScopedPointer to forward declared class
118
119 public:
120 MyClass(); // OK
~MyClass()121 inline ~MyClass() {} // VIOLATION - Destructor must not be inline
122
123 private:
124 Q_DISABLE_COPY(MyClass) // OK - copy constructor and assignment operators
125 // are now disabled, so the compiler won't implicitely
126 // generate them.
127 };
128 //! [4]
129
130 //! [5]
131 // this QScopedPointer deletes its data using the delete[] operator:
132 QScopedPointer<int, QScopedPointerArrayDeleter<int> > arrayPointer(new int[42]);
133
134 // this QScopedPointer frees its data using free():
135 QScopedPointer<int, QScopedPointerPodDeleter> podPointer(reinterpret_cast<int *>(malloc(42)));
136
137 // this struct calls "myCustomDeallocator" to delete the pointer
138 struct ScopedPointerCustomDeleter
139 {
cleanupScopedPointerCustomDeleter140 static inline void cleanup(MyCustomClass *pointer)
141 {
142 myCustomDeallocator(pointer);
143 }
144 };
145
146 // QScopedPointer using a custom deleter:
147 QScopedPointer<MyCustomClass, ScopedPointerCustomDeleter> customPointer(new MyCustomClass);
148 //! [5]
149