Core: Support for converting user defined QVariant types.

This patchs allows the user to convert defined QMetaType types like
MyType to be converted by using e.g. QVariant::toString(), mapping to
MyType::toString(). Also all the other QVariant::toXYZ() methods are
supported so far.

The patch adds static methods QMetaType::registerConverter supporting:
- implicit convertion
- conversion using member method of source type
- conversion using unary functor

Change-Id: I4f1db83d9c78bcc9df5c42f82f95cce0480cdcc3
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>
Reviewed-by: Christoph Schleifenbaum <christoph.schleifenbaum@kdab.com>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>

1 files changed, 3 insertions, 5 deletions

diff --git a/src/corelib/kernel/qvariant.h b/src/corelib/kernel/qvariant.h
index 6f212f5000..0f4102b70a 100644
--- a/src/corelib/kernel/qvariant.h
+++ b/src/corelib/kernel/qvariant.h
@@ -571,11 +571,9 @@ namespace QtPrivate {
             const int vid = qMetaTypeId<T>();
             if (vid == v.userType())
                 return *reinterpret_cast<const T *>(v.constData());
-            if (vid < int(QMetaType::User)) {
-                T t;
-                if (v.convert(vid, &t))
-                    return t;
-            }
+            T t;
+            if (v.convert(vid, &t))
+                return t;
             return T();
         }
 #ifndef QT_NO_QOBJECT