diff --git a/playground/invoker/Invoker.cpp b/playground/invoker/Invoker.cpp
index 59817df3..042c7c0b 100644
--- a/playground/invoker/Invoker.cpp
+++ b/playground/invoker/Invoker.cpp
@@ -13,12 +13,13 @@ Invoker::Invoker( QObject* parent ):
 void Invoker::addCallback( const QObject* object,
     const QskMetaFunction& function )
 {
-    m_callbacks += QskMetaCallback( object, function, Qt::DirectConnection );
+    m_callbacks += QskMetaCallback( object, function );
 }
 
-void Invoker::invoke( qreal realValue, int intValue )
+void Invoker::invoke( qreal realValue, int intValue,
+    Qt::ConnectionType connectionType )
 {
-    for ( auto callback : qskAsConst( m_callbacks ) )
+    for ( auto& callback : m_callbacks )
     {
         void* args[3] = { nullptr };
 
@@ -44,6 +45,11 @@ void Invoker::invoke( qreal realValue, int intValue )
             }
         }
 
-        callback.invoke( args );
+        callback.setConnectionType( connectionType );
+
+        if ( connectionType == Qt::DirectConnection )
+            callback.invoke( args );
+        else if ( callback.object() )
+            callback.invoke( args );
     }
 }
diff --git a/playground/invoker/Invoker.h b/playground/invoker/Invoker.h
index aaf6798e..5b2a4a23 100644
--- a/playground/invoker/Invoker.h
+++ b/playground/invoker/Invoker.h
@@ -20,7 +20,7 @@ public:
     void addCallback( const QskMetaFunction& );
     void addCallback( const QObject*, const QskMetaFunction& );
 
-    void invoke( qreal d, int i );
+    void invoke( qreal d, int i, Qt::ConnectionType );
 
 private:
     QVector< QskMetaCallback > m_callbacks;
diff --git a/playground/invoker/main.cpp b/playground/invoker/main.cpp
index d5858c56..8377cc2a 100644
--- a/playground/invoker/main.cpp
+++ b/playground/invoker/main.cpp
@@ -4,7 +4,9 @@
  *****************************************************************************/
 
 #include "Invoker.h"
+#include <QCoreApplication>
 #include <QDebug>
+#include <QTimer>
 
 static void debugValueI( int i )
 {
@@ -47,8 +49,7 @@ public:
 
 int main( int argc, char* argv[] )
 {
-    Q_UNUSED( argc )
-    Q_UNUSED( argv )
+    QCoreApplication app( argc, argv );
 
     MyObject object;
 
@@ -69,5 +70,14 @@ int main( int argc, char* argv[] )
     invoker.addCallback( []( int i ) { qDebug() << i; } );
     invoker.addCallback( []( double d ) { qDebug() << d; } );
 
-    invoker.invoke( 3.14, 35 );
+    qDebug() << "== Direct Connections";
+    invoker.invoke( 3.14, 35, Qt::DirectConnection );
+
+    qDebug() << "== Queued Connections";
+
+    QTimer::singleShot( 0,
+        [&invoker] { invoker.invoke( 0.07, 42, Qt::QueuedConnection ); } );
+
+    QTimer::singleShot( 100, &app, QCoreApplication::quit );
+    return app.exec();
 }
diff --git a/src/common/QskMetaCall.cpp b/src/common/QskMetaCall.cpp
index fd83aa20..a6b33121 100644
--- a/src/common/QskMetaCall.cpp
+++ b/src/common/QskMetaCall.cpp
@@ -33,6 +33,46 @@ namespace QskMetaCall
     }
 }
 
+namespace
+{
+    using namespace QskMetaCall;
+
+    class FunctionCallEvent : public QMetaCallEvent
+    {
+    public:
+        FunctionCallEvent( Invokable* invokable,
+                int nargs, int* types, void* args[], QSemaphore* semaphore = nullptr ):
+            QMetaCallEvent( invokable, nullptr, 0, nargs, types, args, semaphore ),
+            m_invokable ( invokable )
+        {
+            invokable->ref();
+        }
+
+        virtual ~FunctionCallEvent()
+        {
+        }
+
+    private:
+        Invokable* m_invokable;
+    };
+
+    class MethodCallEvent : public QMetaCallEvent
+    {
+    public:
+        MethodCallEvent( const QMetaObject* mo, ushort methodIndex,
+                int nargs, int* types, void* args[], QSemaphore* semaphore = nullptr ):
+            QMetaCallEvent(
+                mo->methodOffset(), methodIndex, mo->d.static_metacall,
+                nullptr, -1, nargs, types, args, semaphore )
+        {
+        }
+
+        virtual ~MethodCallEvent()
+        {
+        }
+    };
+}
+
 void QskMetaCall::invoke( QObject* object,
     const QMetaMethod& method, void* args[],
     Qt::ConnectionType connectionType )
@@ -66,22 +106,33 @@ void QskMetaCall::invoke( QObject* object,
         const int paramCount = method.parameterCount();
 
         auto types = static_cast< int* >( malloc( paramCount * sizeof( int ) ) );
+        auto arguments = static_cast< void** >( malloc( paramCount * sizeof( void* ) ) );
 
-        types[0] = QMetaType::UnknownType; // return type
+        types[0] = QMetaType::UnknownType; // a return type is not possible
+        arguments[0] = nullptr;
 
         for ( int i = 1; i < paramCount; i++ )
         {
+            if ( arguments[i] == nullptr )
+            {
+                Q_ASSERT( arguments[i] != nullptr );
+
+                free( types );
+                free( arguments );
+
+                return;
+            }
+
             types[i] = method.parameterType( i );
-            Q_ASSERT( args[i] != nullptr );
+            arguments[i] = args[i - 1];
         }
 
         Q_ASSERT( args[paramCount] == nullptr );
 
         if ( connectionType == Qt::QueuedConnection )
         {
-            QMetaCallEvent* event = new QMetaCallEvent(
-                    methodOffset, methodIndex, metaObject->d.static_metacall,
-                    nullptr, -1, paramCount + 1, types, args );
+            auto event = new MethodCallEvent(
+                metaObject, methodIndex, paramCount + 1, types, args );
 
             QCoreApplication::postEvent(object, event );
         }
@@ -89,10 +140,8 @@ void QskMetaCall::invoke( QObject* object,
         {
             QSemaphore semaphore;
 
-            // what about argc + types ???
-            auto event = new QMetaCallEvent(
-                    methodOffset, methodIndex, metaObject->d.static_metacall,
-                    nullptr, -1, 0, 0, args, &semaphore );
+            auto event = new MethodCallEvent(
+                metaObject, methodIndex, paramCount + 1, types, args, &semaphore );
 
             QCoreApplication::postEvent( object, event );
 
@@ -102,7 +151,7 @@ void QskMetaCall::invoke( QObject* object,
 }
 
 void QskMetaCall::invoke( QObject* object,
-    const Invokable& invokable, void* args[],
+    const Invokable& invokable, int argc, const int argTypes[], void* argv[],
     Qt::ConnectionType connectionType )
 {
     //connectionType &= ~Qt::UniqueConnection;
@@ -117,14 +166,36 @@ void QskMetaCall::invoke( QObject* object,
 
     if ( connectionType == Qt::DirectConnection )
     {
-        invokablePtr->call( object, args );
+        invokablePtr->call( object, argv );
     }
     else
     {
+        auto types = static_cast< int* >( malloc( argc * sizeof( int ) ) );
+        auto arguments = static_cast< void** >( malloc( argc * sizeof( void* ) ) );
+
+        types[0] = QMetaType::UnknownType; // a return type is not possible
+        arguments[0] = nullptr;
+
+        for ( int i = 1; i < argc; i++ )
+        {
+            if ( argv[i] == nullptr )
+            {
+                Q_ASSERT( arguments[i] != nullptr );
+
+                free( types );
+                free( arguments );
+
+                return;
+            }
+
+            types[i] = argTypes[i - 1];
+            arguments[i] = QMetaType::create( argTypes[i - 1], argv[i] );
+        }
+
         if ( connectionType == Qt::QueuedConnection )
         {
-            auto event = new QMetaCallEvent(
-                invokablePtr, nullptr, 0, 0, nullptr, args, nullptr );
+            auto event = new FunctionCallEvent(
+                invokablePtr, argc, types, arguments, nullptr );
 
             QCoreApplication::postEvent( object, event );
         }
diff --git a/src/common/QskMetaCall.h b/src/common/QskMetaCall.h
index a3a93bd6..cda99b7f 100644
--- a/src/common/QskMetaCall.h
+++ b/src/common/QskMetaCall.h
@@ -18,7 +18,7 @@ namespace QskMetaCall
         Qt::ConnectionType = Qt::AutoConnection );
 
     QSK_EXPORT void invoke( QObject*,
-        const Invokable&, void* args[],
+        const Invokable&, int argc, const int argTypes[], void* args[],
         Qt::ConnectionType = Qt::AutoConnection );
 }
 
diff --git a/src/common/QskMetaCallback.cpp b/src/common/QskMetaCallback.cpp
index 016f00fd..14a77a91 100644
--- a/src/common/QskMetaCallback.cpp
+++ b/src/common/QskMetaCallback.cpp
@@ -4,82 +4,11 @@
  *****************************************************************************/
 
 #include "QskMetaCallback.h"
-#include <QCoreApplication>
-#include <QThread>
 #include <QObject>
-#include <QSemaphore>
-
-#include <private/qobject_p.h>
-
-static void qskInvoke( QObject* object,
-    const QMetaMethod& method, void* args[], Qt::ConnectionType connectionType )
-{
-    auto metaObject = method.enclosingMetaObject();
-
-    const int methodOffset = metaObject->methodOffset();
-    const int methodIndex  = method.methodIndex() - methodOffset;
-
-    if ( connectionType == Qt::AutoConnection )
-    {
-        connectionType = ( object->thread() == QThread::currentThread() )
-            ? Qt::DirectConnection : Qt::QueuedConnection;
-    }
-
-    if ( connectionType == Qt::DirectConnection )
-    {
-        if ( metaObject->d.static_metacall )
-        {
-            metaObject->d.static_metacall(object,
-                QMetaObject::InvokeMetaMethod, methodIndex, args );
-        }
-        else
-        {
-            QMetaObject::metacall( object,
-                QMetaObject::InvokeMetaMethod, methodIndex, args );
-        }
-    }
-    else
-    {
-        const int paramCount = method.parameterCount();
-
-        auto types = static_cast< int* >( malloc( paramCount * sizeof( int ) ) );
-
-        types[0] = QMetaType::UnknownType; // return type
-
-        for ( int i = 1; i < paramCount; i++ )
-        {
-            types[i] = method.parameterType( i );
-            Q_ASSERT( args[i] != nullptr );
-        }
-
-        Q_ASSERT( args[paramCount] == nullptr );
-
-        if ( connectionType == Qt::QueuedConnection )
-        {
-            QMetaCallEvent* event = new QMetaCallEvent(
-                    methodOffset, methodIndex, metaObject->d.static_metacall,
-                    nullptr, -1, paramCount + 1, types, args );
-
-            QCoreApplication::postEvent(object, event );
-        }
-        else
-        {
-            QSemaphore semaphore;
-
-            // what about argc + types ???
-            auto event = new QMetaCallEvent(
-                methodOffset, methodIndex, metaObject->d.static_metacall,
-                nullptr, -1, 0, 0, args, &semaphore );
-
-            QCoreApplication::postEvent( object, event );
-
-            semaphore.acquire();
-        }
-    }
-}
+#include <QVector>
 
 QskMetaCallback::QskMetaCallback( const QObject* object,
-    const QMetaMethod& method, Qt::ConnectionType connectionType ):
+        const QMetaMethod& method, Qt::ConnectionType connectionType ):
     m_object( const_cast< QObject* >( object ) ),
     m_method( method ),
     m_type( MetaMethod ),
@@ -156,6 +85,11 @@ QskMetaCallback& QskMetaCallback::operator=( const QskMetaCallback& other )
     return *this;
 }
 
+void QskMetaCallback::setConnectionType( Qt::ConnectionType connectionType )
+{
+    m_connectionType = connectionType;
+}
+
 void QskMetaCallback::reset()
 {
     switch( m_type )
@@ -218,7 +152,7 @@ void QskMetaCallback::invoke( void* args[] )
         case MetaMethod:
         {
             if ( object )
-                qskInvoke( object, m_method, args, connectionType() );
+                QskMetaCall::invoke( object, m_method, args, connectionType() );
             break;
         }
         case MetaFunction:
diff --git a/src/common/QskMetaCallback.h b/src/common/QskMetaCallback.h
index 97be0806..09097434 100644
--- a/src/common/QskMetaCallback.h
+++ b/src/common/QskMetaCallback.h
@@ -12,6 +12,7 @@
 #include <QObject>
 #include <QPointer>
 #include <QMetaMethod>
+#include <QVector>
 
 class QskMetaCallback
 {
@@ -28,8 +29,13 @@ public:
     };
 
     QskMetaCallback();
-    QskMetaCallback( const QObject*, const QskMetaFunction&, Qt::ConnectionType );
-    QskMetaCallback( const QObject*, const QMetaMethod&, Qt::ConnectionType );
+
+    QskMetaCallback( const QObject*, const QskMetaFunction&,
+        Qt::ConnectionType = Qt::AutoConnection );
+
+    QskMetaCallback( const QObject*, const QMetaMethod&,
+        Qt::ConnectionType = Qt::AutoConnection );
+
     QskMetaCallback( const QskMetaCallback& );
 
     ~QskMetaCallback();
@@ -40,6 +46,8 @@ public:
     bool isValid() const;
 
     const QObject* object() const { return m_object; }
+
+    void setConnectionType( Qt::ConnectionType );
     Qt::ConnectionType connectionType() const;
 
     QVector< int > parameterTypes() const;
@@ -51,11 +59,17 @@ private:
 
     QPointer< const QObject > m_object;
 
+#if 1
+    /*
+        This union does not work - call of constructors
+        are missing
+     */
     union
     {
         QskMetaFunction m_function;
         QMetaMethod m_method;
     };
+#endif
 
     int m_type : 3;
     ushort m_connectionType : 3;
diff --git a/src/common/QskMetaFunction.cpp b/src/common/QskMetaFunction.cpp
index ebd0299c..7cbde28c 100644
--- a/src/common/QskMetaFunction.cpp
+++ b/src/common/QskMetaFunction.cpp
@@ -68,11 +68,38 @@ QskMetaFunction& QskMetaFunction::operator=( const QskMetaFunction& other )
     return *this;
 }
 
+void QskMetaFunction::init( QskMetaCall::Invokable* invokable,
+    const int* parameterTypes )
+{
+    m_invokable = invokable;
+#if 0
+    if ( m_invokable )
+        m_invokable->ref();
+#endif
+
+    m_parameterTypes = parameterTypes;
+}
+
 const int* QskMetaFunction::parameterTypes() const
 {
     return m_parameterTypes;
 }
 
+size_t QskMetaFunction::parameterCount() const
+{
+    if ( m_parameterTypes )
+    {
+        for ( int i = 1; ; i++ )
+        {
+            if ( m_parameterTypes[ i ] == QMetaType::UnknownType )
+                return i + 1; // including the return type
+        }
+    }
+
+    return 1; // we always have a return type
+}
+
+
 QskMetaFunction::Type QskMetaFunction::functionType() const
 {
     if ( m_invokable == nullptr )
@@ -82,8 +109,11 @@ QskMetaFunction::Type QskMetaFunction::functionType() const
 }
 
 void QskMetaFunction::invoke(
-    QObject* object, void* args[], Qt::ConnectionType connectionType )
+    QObject* object, void* argv[], Qt::ConnectionType connectionType )
 {
     if ( m_invokable )
-        QskMetaCall::invoke( object, *m_invokable, args, connectionType );
+    {
+        QskMetaCall::invoke( object, *m_invokable,
+            parameterCount(), parameterTypes(), argv, connectionType );
+    }
 }
diff --git a/src/common/QskMetaFunction.h b/src/common/QskMetaFunction.h
index bad1a2ce..13a7369b 100644
--- a/src/common/QskMetaFunction.h
+++ b/src/common/QskMetaFunction.h
@@ -53,12 +53,17 @@ public:
 
     const int* parameterTypes() const;
 
+    // including the return type !
+    size_t parameterCount() const;
+
     void invoke( QObject*, void* args[],
         Qt::ConnectionType = Qt::AutoConnection );
 
     Type functionType() const;
 
 private:
+    void init( QskMetaCall::Invokable*, const int* );
+
     QskMetaCall::Invokable* m_invokable;
     const int* m_parameterTypes;
 };
@@ -75,8 +80,8 @@ inline QskMetaFunction::QskMetaFunction( T function )
     const int Argc = Traits::ArgumentCount;
     using Args = typename List_Left< typename Traits::Arguments, Argc >::Value;
 
-    m_invokable = new MemberFunctionInvokable< T, Args, void >( function );
-    m_parameterTypes = ConnectionTypes< typename Traits::Arguments >::types();
+    init( new MemberFunctionInvokable< T, Args, void >( function ),
+        ConnectionTypes< typename Traits::Arguments >::types() );
 }
 
 template< typename T, QskMetaCall::IsFunction< T >* >
@@ -90,8 +95,8 @@ inline QskMetaFunction::QskMetaFunction( T function )
     const int Argc = Traits::ArgumentCount;
     using Args = typename List_Left< typename Traits::Arguments, Argc >::Value;
 
-    m_invokable = new FunctionInvokable< T, Args, void >( function );
-    m_parameterTypes = ConnectionTypes< typename Traits::Arguments >::types();
+    init( new FunctionInvokable< T, Args, void >( function ),
+        ConnectionTypes< typename Traits::Arguments >::types() );
 }
 
 template< typename T, QskMetaCall::IsFunctor< T >* >
@@ -104,8 +109,8 @@ inline QskMetaFunction::QskMetaFunction( T functor )
     const int Argc = Traits::ArgumentCount;
     using Args = typename List_Left< typename Traits::Arguments, Argc >::Value;
 
-    m_invokable = new QskMetaCall::FunctorInvokable< T, Argc, Args, void > ( functor );
-    m_parameterTypes = ConnectionTypes< typename Traits::Arguments >::types();
+    init( new QskMetaCall::FunctorInvokable< T, Argc, Args, void > ( functor ),
+        ConnectionTypes< typename Traits::Arguments >::types() );
 }
 
 Q_DECLARE_METATYPE( QskMetaFunction )