apply initializer after object creation in SelectionProperty

GUI/Model/Descriptor/SelectionProperty.h

@@ -162,6 +162,8 @@ public:
         const uint typeIndex = XML::readUIntAttribute(r, XML::Attrib::type);
         const auto type = static_cast<typename Catalog::Type>(typeIndex);
         auto* p = Catalog::create(type, argsForCreation...);
+        if (m_initializer)
+            m_initializer(p, m_p.get());
         if (p)
             p->readFrom(r);
         m_p.reset(p);