Who in the novel To Kill A Mockingbird has more direct and indirect characterization that shows that they're a brave person?Which character is the...

Atticus is a fine example of courage, as pointed out by my colleague's great answer.  His is a moral courage and conviction which we all admire.  I'd like to make a case for someone she alluded to, Mrs. Dubose, as being another excellent example of courage in this novel. Hers is an inner strength, one which Atticus also finds commendable. 

Indirectly, we see Mrs. Henry Lafayette DuBose as a strong woman, armed and ready to defend herself.  Her tongue is sharp and she is unafraid to speak her mind--even if she is belittling and prejudiced as she does so.

Later, when Jem and Scout are at her bedside, the picture is not pretty and she looks anything but courageous.  Strings of saliva and drool are off-putting, to say the least; and she regularly drifts in and out of alertness as they read to her.  These are indicators, we later find out, of a woman who is suffering the pangs and punishments of withdrawal from a potent drug.  She doesn't scream or shout or cry; she simply concentrates and overcomes.

Direct characterization of her courage comes from Atticus, as mentioned, when he uses her as an example to Jem and Scout.  He informs them of her morphine addiction and her bravery in overcoming her dependence. Only when we hear this do the items mentioned above look like courage, both to the reader and to the kids.

Mrs. DuBose could easily have lived the rest of her life dependent on the drug and content to see the world through a morphine haze.  Instead, she exhibits a personal courage which even Atticus finds astounding.