Feeds
Barton was spotted kissing the rocker at a memorial gig for Brandon Schantz at LA's The Roxy Theatre, say US reports. The actress also ate lunch with Locke earlier in the day.
A source said: "Mischa was singing along and dancing as Rooney were playing. Literally as soon as they had finished she dashed over to the stage and gave him a big kiss on the lips.
"She was holding him around the waist and looked really happy."
The band formed in 1999 and have released four albums together.
Barton's former boyfriends include Whitestarr frontman Cisco Adler and American socialite Brandon Davies.
