How to change Title font size in Listview

Modifying listview example:

using the statement: " ren_attr(:song, :size=18)"
changes the text font size of :song column,
but does not change the textfont size of the column title.

What is the example statement to change the title text size
of column :song?

Thanks, John

In the listview example there’s a method that set the alignment of the

def center__toggled(*argv)
val = @builder[“center”].active? ? 0.5 : 0
col_alignment(:artist => val)

This is setting a property in the Gtk::TreeViewColumn object. I don’t
see a way to get access to the text inside the title except that there
is a widget property:

Perhaps you can get that widget, check its type and set the text size???