Remove QPropertyMemberChangeHandler again

Adding support for a static notifier within QProperty itself - through a
QProperty "sister" class - is more efficient in terms of memory
consumption and run-time performance.

The MemberChangeHandler permanently takes up at least three pointers,
while the notified properties only cost one pointer in the binding.

Change-Id: Ia1a8c2b66f1f3c2fe13ae0ad9f12cdb6bdcc35ef
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 0 insertions, 23 deletions

diff --git a/src/corelib/kernel/qproperty.h b/src/corelib/kernel/qproperty.h
index 5ba4d2eda7..de08a71349 100644
--- a/src/corelib/kernel/qproperty.h
+++ b/src/corelib/kernel/qproperty.h
@@ -731,28 +731,6 @@ QPropertyChangeHandler<Functor> QNotifiedProperty<T, Callback, ValueGuard>::subs
     return onValueChanged(f);
 }
 
-template <auto propertyMember, auto callbackMember>
-struct QPropertyMemberChangeHandler;
-
-template<typename Class, typename PropertyType, PropertyType Class::* PropertyMember, void(Class::*Callback)()>
-struct QPropertyMemberChangeHandler<PropertyMember, Callback> : public QPropertyObserver
-{
-    QPropertyMemberChangeHandler(Class *obj)
-        : QPropertyObserver(notify)
-    {
-        setSource(obj->*PropertyMember);
-    }
-
-    static void notify(QPropertyObserver *, void *propertyDataPtr)
-    {
-        // memberOffset is the offset of the QProperty<> member within the class. We get the absolute address
-        // of that member and subtracting the relative offset gives us the address of the class instance.
-        const size_t memberOffset = reinterpret_cast<size_t>(&(static_cast<Class *>(nullptr)->*PropertyMember));
-        Class *obj = reinterpret_cast<Class *>(reinterpret_cast<char *>(propertyDataPtr) - memberOffset);
-        (obj->*Callback)();
-    }
-};
-
 template<typename T>
 class QPropertyAlias : public QPropertyObserver
 {
@@ -892,7 +870,6 @@ public:
         return aliasedProperty<T>() != nullptr;
     }
 };
-
 QT_END_NAMESPACE
 
 #endif // QPROPERTY_H