GtkLabel::set_pattern
void set_pattern([string
pattern = NULL
]);
set_pattern() is the method
for underlining text in GtkLabel. It needs
to be defined as a pattern, e.g. if your text consists of
A B C, then "_ _"
will underline A and C but
not B, as that is where the space falls. Each
underscore or space in the pattern maps directly to the character
position in the label text.
$label->set_pattern("_ _");
Call this method with no parameters to erase existing underlines.