A. It shall be unlawful for any person to point, hold or brandish any firearm or any air or gas operated weapon or any object similar in appearance, whether capable of being fired or not, in such manner as to reasonably induce fear in the mind of another or hold a firearm or any air or gas operated weapon in a public place in such a manner as to reasonably induce fear in the mind of another of being shot or injured.
Since open carry is lawful in Virginia merely exposing a concealed weapon accidentally is surely not brandishing within the meaning of the law. IMO to brandish must be an intentional act to threaten or intimidate another.
We have several technical problems: Brandishing is not defined by Code of Virginia therefore we must refer to dictionary definition. “Brandish” means “to exhibit or expose in an ostentatious, shameless, or aggressive manner.” Webster's Third New International Dictionary, 268 (1993).
So from that we can conclude that yes, under the right circumstances, merely touching your gun could be considered brandishing. Much depends on intent - often that is like mind reading - not sufficient to warrant a conviction.