.. _Add Virtual Qualifier to Interface Type:

Add Virtual Qualifier to Interface Type
=======================================

When declaring a method argument of **interface** type without using the **virtual** qualifier, DVT raises an error.

.. figure:: ../../images/common/sv_quick_fix_add_virtual_qualifier_list.png

Place the editor cursor on the error's line and press :kbd:`Ctrl+1`, select **Add 'virtual' qualifier** from the list of quick fix proposals and press  :kbd:`Enter`.

The 'virtual' qualifier is automatically added to the argument declaration.

.. figure:: ../../images/common/sv_quick_fix_add_virtual_qualifier_after.png

