navidemo 正常入栈顺序 A -> RN01 -> RN02 -> B -> RN01 理论出栈顺序 A -> RN01 -> RN02 -> B A -> RN01 -> RN02 A -> RN01 A -> gif 显示的后退顺序 A -> RN01 -> RN02 -> B -> A -> RN01 -> B A -> RN01 A ->