Throughout the narrative of To Kill a Mockingbird, Atticus Finch demonstrates self-control, or the ability to control one's desires or emotions in difficult situations. Here are some other situations that are not mentioned in the previous post:

• Unlike many a parent who would be angry with a teacher who has insulted the parent by saying that he "does not know how to teach" and should, therefore, not engage in reading activities with his child, Atticus calmly tells the infuriated Scout that sometimes a person must try to see things as the other party does by "climb[ing] his skin and walk[ing] around in it" (Chapter 3). Also, if Scout will agree, they will "compromise" by not saying anything to Miss Caroline, but continue together to have their evening reading sessions.
• In the very stressful situation of the approach of the mad dog (Chapter 10) named Tim Johnson, Atticus demonstrates self-control as he calmly finds and kills the dog with the rifle Sheriff Tate tossed to him.
• Certainly, in the courtroom with both the hostile Bob Ewell and Mayella Ewell, Atticus maintains control of himself as he interrogates Mr. Ewell when asking about his being left-handed (Chapter 17). Also, during his examination of Mayella Ewell,  Mayella appeals even to the judge that Atticus not be allowed to question her:

"Long's he keeps on callin' me ma'am an sayin' Miss Mayella, I don't hafta take his sass, I ain't called upon to take it" (Chapter 18).

Atticus remains calm and polite to Miss Mayella, and his questions are allowed (Chapter 18).

Yes. Atticus is the novel's morally upright character, and there are numerous scenes that depict Atticus displaying self-control. In Chapter 11, Scout recounts how her father reacts to Mrs. Henry Lafayette Dubose's ignorant comments. Scout mentions that every time Atticus would pass her house he would politely say, "Good evening, Mrs. Dubose! You look like a picture this evening," and would wish her a happy day. (Lee 134) Atticus is aware that she makes derogatory comments directed towards him and the children. He tells Jem that it's his job to not let her make him mad. Atticus displays tolerance and self-control by not reacting aggressively or taking offense to her comments. Instead, Atticus keeps a "level head" and treats her with respect and kindness.

Later on in the novel, Bob Ewell runs into Atticus at the post office following the trial. Bob Ewell is bitter and begins to curse and insult Atticus in public. When Bob Ewell spits in Atticus' face, Atticus calmly takes out his handkerchief and wipes it off. Bob even challenges him by saying, "Too proud to fight, you nigger-lovin' bastard?" and Atticus simply says, "No, too old" and walks away. (Lee 290) This is the clearest example of Atticus displaying self-control in the novel. He understands Bob's difficult position and lets him vent his anger. Instead of reacting with anger, Atticus endures Bob's insults and calmly walks away.