Add some internal API for extracting a QSharedPointer<T> from QVariant.

The T must be derived from QObject, or it will fail to compile.

This will allow scripting or other 'wrapping' and runtime environments like
QtDeclarative to handle QSharedPointers to types derived from QObject
properly. A QSharedPointer<T> can be inserted into a QVariant, and
where T derives from QObject, a QSharedPointer<QObject> can be
extracted from the QVariant, and its properties are then accessible.

Change-Id: I68d6d89aceceb019267bd7301baa2047f9c09b90
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 19 insertions, 1 deletions

diff --git a/src/corelib/tools/qsharedpointer_impl.h b/src/corelib/tools/qsharedpointer_impl.h
index 46cd1cc0a7..9d9698b8ca 100644
--- a/src/corelib/tools/qsharedpointer_impl.h
+++ b/src/corelib/tools/qsharedpointer_impl.h
@@ -87,6 +87,8 @@ template<typename T> inline void qt_sharedpointer_cast_check(T *) { }
 template <class T> class QWeakPointer;
 template <class T> class QSharedPointer;
 
+class QVariant;
+
 template <class X, class T>
 QSharedPointer<X> qSharedPointerCast(const QSharedPointer<T> &ptr);
 template <class X, class T>
@@ -258,6 +260,9 @@ namespace QtSharedPointer {
         ~ExternalRefCountWithContiguousData() Q_DECL_EQ_DELETE;
         Q_DISABLE_COPY(ExternalRefCountWithContiguousData)
     };
+
+    Q_CORE_EXPORT QWeakPointer<QObject> weakPointerFromVariant_internal(const QVariant &variant);
+    Q_CORE_EXPORT QSharedPointer<QObject> sharedPointerFromVariant_internal(const QVariant &variant);
 } // namespace QtSharedPointer
 
 template <class T> class QSharedPointer
@@ -816,8 +821,21 @@ qobject_cast(const QWeakPointer<T> &src)
 {
     return qSharedPointerObjectCast<typename QtSharedPointer::RemovePointer<X>::Type, T>(src);
 }
-#endif
 
+template<typename T>
+QWeakPointer<typename QtPrivate::QEnableIf<QtPrivate::IsPointerToTypeDerivedFromQObject<T*>::Value, T>::Type>
+qWeakPointerFromVariant(const QVariant &variant)
+{
+    return QWeakPointer<T>(qobject_cast<T*>(QtSharedPointer::weakPointerFromVariant_internal(variant).data()));
+}
+template<typename T>
+QSharedPointer<typename QtPrivate::QEnableIf<QtPrivate::IsPointerToTypeDerivedFromQObject<T*>::Value, T>::Type>
+qSharedPointerFromVariant(const QVariant &variant)
+{
+    return qSharedPointerObjectCast<T>(QtSharedPointer::sharedPointerFromVariant_internal(variant));
+}
+
+#endif
 
 template<typename T> Q_DECLARE_TYPEINFO_BODY(QWeakPointer<T>, Q_MOVABLE_TYPE);
 template<typename T> Q_DECLARE_TYPEINFO_BODY(QSharedPointer<T>, Q_MOVABLE_TYPE);