SAN DIEGO — Warner Bros. unveiled sizzling footage on Saturday from upcoming movies like “Ready Player One,” “Justice League” and “Blade Runner 2049” at Comic-Con International here. The studio also confirmed that its superhero lineup in the decade ahead will include “Wonder Woman 2,” “Bat Girl” and “Green Lantern Corps.”

But it was a rare announcement of something not happening that sent the fan convention spinning: Ben Affleck, looking a little grumpy, denied a report that his days as Batman are numbered.

“I’m Batman,” he said, as 6,500 people inside Hall H at the San Diego Convention Center roared their approval. Mr. Affleck said that he had spoken to several senior Warner Bros. executives, including the studio’s chairman, Kevin Tsujihara. “‘We want you to be the Batman,’ they told me, and I believe them,” Mr. Affleck said. “I’m so thrilled to do it.”

An article in The Hollywood Reporter on Friday said that Mr. Affleck’s future was in doubt — the equivalent of a sonic boom in the superhero movie world. Citing an anonymous source, the article said that Warner Bros. was “working on plans to usher out” an aging Mr. Affleck.