1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
|
//
// Observer.h
//
// Library: Foundation
// Package: Notifications
// Module: NotificationCenter
//
// Definition of the Observer class template.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_Observer_INCLUDED
#define Foundation_Observer_INCLUDED
#include "Poco/Foundation.h"
#include "Poco/AbstractObserver.h"
#include "Poco/Mutex.h"
namespace Poco {
template <class C, class N>
class Observer: public AbstractObserver
/// This template class implements an adapter that sits between
/// a NotificationCenter and an object receiving notifications
/// from it. It is quite similar in concept to the
/// RunnableAdapter, but provides some NotificationCenter
/// specific additional methods.
/// See the NotificationCenter class for information on how
/// to use this template class.
///
/// Instead of the Observer class template, you might want to
/// use the NObserver class template, which uses an AutoPtr to
/// pass the Notification to the callback function, thus freeing
/// you from memory management issues.
{
public:
typedef void (C::*Callback)(N*);
Observer(C& object, Callback method):
_pObject(&object),
_method(method)
{
}
Observer(const Observer& observer):
AbstractObserver(observer),
_pObject(observer._pObject),
_method(observer._method)
{
}
~Observer()
{
}
Observer& operator = (const Observer& observer)
{
if (&observer != this)
{
_pObject = observer._pObject;
_method = observer._method;
}
return *this;
}
void notify(Notification* pNf) const
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_pObject)
{
pNf->duplicate();
(_pObject->*_method)(static_cast<N*>(pNf));
}
}
bool equals(const AbstractObserver& abstractObserver) const
{
const Observer* pObs = dynamic_cast<const Observer*>(&abstractObserver);
return pObs && pObs->_pObject == _pObject && pObs->_method == _method;
}
POCO_DEPRECATED("use `bool accepts(const Notification::Ptr&)` instead")
bool accepts(Notification* pNf, const char* pName) const
{
return (!pName || pNf->name() == pName) && (dynamic_cast<N*>(pNf) != nullptr);
}
bool accepts(const Notification::Ptr& pNf) const
{
return (pNf.cast<N>() != nullptr);
}
AbstractObserver* clone() const
{
return new Observer(*this);
}
void disable()
{
Poco::Mutex::ScopedLock lock(_mutex);
_pObject = 0;
}
private:
Observer();
C* _pObject;
Callback _method;
mutable Poco::Mutex _mutex;
};
} // namespace Poco
#endif // Foundation_Observer_INCLUDED
|
