"The blood that flows through America that is from gun violence is mostly African-American, and yet you young black folk sit here mute and ya'll don't say nothing about it," Foxx said.
"I said you've got me for life, man," Foxx said of his support for Martin's parents, Sabrina Fulton and
Tracy Martin. "Don't think that Hollywood isn't thinking about you. Everyone that I talk to wants to be here or is tweeting right now or Instagramming or myfacing or whatever they call it. You young people know what it is. Whatever it is, but they are doing that."
Foxx promoted the event via his Twitter page, telling followers that commemorating Martin was "not about race, not about color, but about PEACE for our children!"
Neighborhood watchman George Zimmerman was acquitted last year in the shooting death of 17-year-old Martin, which launched a nationwide discussion about Florida's so-called "Stand Your Ground" laws.
Zimmerman recently said he would take on anyone in a fight, but his boxing match with rapper DMX was canceled on Sunday.
"We choose not to expand any energy on that situation," Martin's father, Tracy, said of the bout on Saturday. "If you consider yourself a celebrity after you killed a child, something's wrong with you. I have a problem with that."