API CollapseTrainerSkillLine

Collapses a header in the trainer window, hiding all spells below it.
 CollapseTrainerSkillLine(index)
==Arguments==
:;index: - The index of a line in the trainer window (if the supplied index is not a header, an error is produced).
::Index 0 ("All") will collapse all headers.
::Note that indices are affected by the trainer filter, see () and ()
==Example==
Collapses all trainer headers. This can also be done by using index 0 instead.
 for i = 1, GetNumTrainerServices() do
 	local category = select(3, GetTrainerServiceInfo(i))
 	if category == "header" then
 		CollapseTrainerSkillLine(i)
 	end
 end
==Patch changes==
==See also==
* ()