The 28-year-old, who joined the Cherries from hometown side Swansea City, has put pen-to-paper on a two-year deal with the Latics.
The popular welshman departs Vitality Stadium after five years at the club, in which the midfielder helped the club earn promotion all the way from League One to the Premier League.
He made 101 appearances for the club after joining from Swansea City in August 2011.
