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27 #ifndef LifecycleObserver_h
28 #define LifecycleObserver_h
30 #include "wtf/Assertions.h"
35 class LifecycleObserver {
41 DocumentLifecycleObserverType,
43 PageLifecycleObserverType,
44 DOMWindowLifecycleObserverType
47 explicit LifecycleObserver(Context* context, Type type = GenericType)
48 : m_lifecycleContext(context)
49 , m_observerType(type)
51 observeContext(context);
54 virtual ~LifecycleObserver()
59 virtual void contextDestroyed() { m_lifecycleContext = 0; }
62 Context* lifecycleContext() const { return m_lifecycleContext; }
63 Type observerType() const { return m_observerType; }
66 void observeContext(Context*);
68 Context* m_lifecycleContext;
73 // These functions should be specialized for each LifecycleObserver instances.
75 template<typename T> void observerContext(T*, LifecycleObserver<T>*) { ASSERT_NOT_REACHED(); }
76 template<typename T> void unobserverContext(T*, LifecycleObserver<T>*) { ASSERT_NOT_REACHED(); }
80 inline void LifecycleObserver<T>::observeContext(typename LifecycleObserver<T>::Context* context)
82 if (m_lifecycleContext)
83 unobserverContext(m_lifecycleContext, this);
85 m_lifecycleContext = context;
87 if (m_lifecycleContext)
88 observerContext(m_lifecycleContext, this);
91 } // namespace WebCore
93 #endif // LifecycleObserver_h