I remember hearing somewhere that Companions could approve / disapprove even if they heard about something "second hand", meaning they are not actually physically with your Inquisitor when you make a decision. If this is true, I don't like it. In DAO and DA2, I preferred to keep certain Companions out of the active party if I knew (before-hand) that they would object to a decision I was about to make. As an example, I made sure a certain character was not in my party before doing one of the quests in DAO...
I wonder to what extent this would go. In Awakenings, for example, if you took the sidequest aiding the Templars to find apostates in the City of Amaranthine, you will immediately get disapproval from Anders even if you left him at the Keep. Of course, Awakening is bugged all to hell so that might be the reason why too but I can never tell.
Anyway, I'd like to think that approval or disapproval based on secondhand knowledge would only really extend to the bigger decisions. Like, if I did something kinda mean to some random merchant in Craptown, Thedas, it'd be kind of weird for word of that to really spread back to the home base.