[ Version ( since = "1.20" ) ]
public void init (AttrClass klass)
Initializes this's klass to klass, it's start_index to
pango_attr_index_from_text_beginning and end_index to pango_attr_index_to_text_end such that
the attribute applies to the entire text by default.
| this |
a `PangoAttribute` |
| klass |
a `PangoAttrClass` |