The interface text box displays the name of the current interface; the interface that you are currently working on. Note that there may be several other interfaces loaded into the Interface Builder, but only one can be current.
To switch to another loaded interface, or to create a new interface, type the name of the interface into this area and press
. You might find it useful to type just a few characters and then press
to invoke in-place completion. The interface you specify appears and its layouts are shown in the Interface Builder.
LispWorks IDE User Guide (Windows version) - 25 Nov 2011