ChordNames on Staff

[Robert Hennig]

Dear lilypond community,

I would like to print the ChordNames casually directly on the staff, Not
above the staff. Using extra-offset works if there are no other objects
which adjusts the spacing. What is the proper way to get the ChordNames
fixed to the staff?
I would like to create lead sheets which contain lots of remarks, only
sometimes there are notes in the staff.
Uncomment the Annotation to see what I mean.
Regards Robert

\version "2.19.82"
<<
  \new ChordNames \chordmode {
    \override ChordNames.ChordName #'extra-offset = #'(0 . -3.5)
    c1
  }
  s1%^"Text"
>>