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39
40 #include <QtGui/qtguiglobal.h>
41 #if QT_CONFIG(accessibility)
42
43 #include "qwindowsuiaprovidercache.h"
44 #include "qwindowsuiautils.h"
45 #include "qwindowscontext.h"
46
47 QT_BEGIN_NAMESPACE
48
49 using namespace QWindowsUiAutomation;
50
51
52 // Private constructor
QWindowsUiaProviderCache()53 QWindowsUiaProviderCache::QWindowsUiaProviderCache()
54 {
55 }
56
57 // shared instance
instance()58 QWindowsUiaProviderCache *QWindowsUiaProviderCache::instance()
59 {
60 static QWindowsUiaProviderCache providerCache;
61 return &providerCache;
62 }
63
64 // Returns the provider instance associated with the ID, or nullptr.
providerForId(QAccessible::Id id) const65 QWindowsUiaBaseProvider *QWindowsUiaProviderCache::providerForId(QAccessible::Id id) const
66 {
67 return m_providerTable.value(id);
68 }
69
70 // Inserts a provider in the cache and associates it with an accessibility ID.
insert(QAccessible::Id id,QWindowsUiaBaseProvider * provider)71 void QWindowsUiaProviderCache::insert(QAccessible::Id id, QWindowsUiaBaseProvider *provider)
72 {
73 remove(id);
74 if (provider) {
75 m_providerTable[id] = provider;
76 m_inverseTable[provider] = id;
77 // Connects the destroyed signal to our slot, to remove deleted objects from the cache.
78 QObject::connect(provider, &QObject::destroyed, this, &QWindowsUiaProviderCache::objectDestroyed);
79 }
80 }
81
82 // Removes deleted provider objects from the cache.
objectDestroyed(QObject * obj)83 void QWindowsUiaProviderCache::objectDestroyed(QObject *obj)
84 {
85 // We have to use the inverse table to map the object address back to its ID,
86 // since at this point (called from QObject destructor), it has already been
87 // partially destroyed and we cannot treat it as a provider.
88 auto it = m_inverseTable.find(obj);
89 if (it != m_inverseTable.end()) {
90 m_providerTable.remove(*it);
91 m_inverseTable.remove(obj);
92 }
93 }
94
95 // Removes a provider with a given id from the cache.
remove(QAccessible::Id id)96 void QWindowsUiaProviderCache::remove(QAccessible::Id id)
97 {
98 m_inverseTable.remove(m_providerTable.value(id));
99 m_providerTable.remove(id);
100 }
101
102 QT_END_NAMESPACE
103
104 #endif // QT_CONFIG(accessibility)
105