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39
40#include "qqmlcleanup_p.h"
41
42#include "qqmlengine_p.h"
43
44QT_BEGIN_NAMESPACE
45
46/*!
47\internal
48\class QQmlCleanup
49\brief The QQmlCleanup provides a callback when a QQmlEngine is deleted.
50
51Any object that needs cleanup to occur before the QQmlEngine's V8 engine is
52destroyed should inherit from QQmlCleanup. The clear() virtual method will be
53called by QQmlEngine just before it destroys the context.
54*/
55
56
57/*
58Create a QQmlCleanup that is not associated with any engine.
59*/
60QQmlCleanup::QQmlCleanup()
61: prev(nullptr), next(nullptr), engine(nullptr)
62{
63}
64
65/*!
66Create a QQmlCleanup for \a engine
67*/
68QQmlCleanup::QQmlCleanup(QQmlEngine *engine)
69: prev(nullptr), next(nullptr), engine(nullptr)
70{
71 if (!engine)
72 return;
73
74 addToEngine(engine);
75}
76
77/*!
78Adds this object to \a engine's cleanup list. hasEngine() must be false
79before calling this method.
80*/
81void QQmlCleanup::addToEngine(QQmlEngine *engine)
82{
83 Q_ASSERT(engine);
84 Q_ASSERT(QQmlEnginePrivate::isEngineThread(engine));
85
86 this->engine = engine;
87
88 QQmlEnginePrivate *p = QQmlEnginePrivate::get(engine);
89
90 if (p->cleanup) next = p->cleanup;
91 p->cleanup = this;
92 prev = &p->cleanup;
93 if (next) next->prev = &next;
94}
95
96/*!
97\fn bool QQmlCleanup::hasEngine() const
98
99Returns true if this QQmlCleanup is associated with an engine, otherwise false.
100*/
101
102/*!
103\internal
104*/
105QQmlCleanup::~QQmlCleanup()
106{
107 Q_ASSERT(!prev || engine);
108 Q_ASSERT(!prev || QQmlEnginePrivate::isEngineThread(engine));
109
110 if (prev) *prev = next;
111 if (next) next->prev = prev;
112 prev = nullptr;
113 next = nullptr;
114}
115
116QT_END_NAMESPACE
117