Register QTreeView To Qml using QGraphicsProxyWidget (QtQuick 2.0)

I am trying to embed QTreeView into QML using QGraphicsProxyWidget. When I run my programme, there is a error hint that tells me my registered item is a QtQuick 1.0 item and it cannot be used in QtQuick 2.0。Does it mean the subclass of QGraphicsProxyWidget can only be registered to a QtQuick 1.0 component? Or is there any misusing in my programme? Thank you for your help!