So i was wondering if any one knows how do power button works with multi select, since my goal is to make similar button but i kinda stuck on that multi select part :P
I think this is key method for your problem.
In Class Command:
public override bool GroupsWith(Gizmo other)
{
Command command = other as Command;
return command != null && (this.hotKey == command.hotKey && this.defaultLabel == command.defaultLabel && (Object) this.icon == (Object) command.icon || this.groupKey != 0 && command.groupKey != 0 && this.groupKey == command.groupKey);
}
The EdB Interface may be a good place to look. Doesn't it allow that for hunting and hauling?