after-new-child

This method is called after a new containee area is created with this area as its container. The new child is provided as an argument to the method.

• (send a-panel:single-mixin after-new-child child) -> void
      child : subarea<%>

  Does nothing.

  Hides this child by calling

    (send child show #f) 
  

  , unless this is the first child in which case it does nothing.