It's also worth knowing that black people don't simply "protest" violence in their communities, they often approach the very people doing the violence. Here's the trailer for The Interrupters, a film that captures black and brown people in Chicago, doing precisely the sort of work which people like Juan Williams should be applauding.
There's some talk that the problem is the media, in that they don't focus on stories like those brought forth in The Interrupters. I'm all for more media attention on the efforts like those in The Interrupters. But your ignorance is not the media's fault. If you make an affirmative claim--that no one protests violence in inner cities--without doing a rudimentary google search, the problem is your laziness, not the media's coverage.
The Interrupters is on PBS's Frontline, streaming. Right now. Watch the film. If you do not know it's because you don't want to.