flutter column里面的item写法

Column(
                                  children: onLineContributeShowList.isEmpty
                                      ? [Container()]
                                      : onLineContributeShowList
                                          .map((e) => contributeListItem(
                                                userInfoList: e,
                                                roomId: widget.roomId,
                                                anchorInfo: widget.anchorInfo,
                                                userRole: widget.userRole,
                                                source: 1,
                                              ))
                                          .toList(),
                                )