I am new to flutter, and I'm facing some layout errors that I cannot understand. Does someone knows why this error occurs? I know that ***Column widget*** cannot contain the ***Listview*** widget so I tried to wrap ***Listview*** widget with the ***Expanded***, I cannot understand why the ***Expanded*** widget doens't work.

Here is my code. \_buildBody function is not the part that error occurs so I will not write it.

```
Widget build(BuildContext context) {
return Column(
  mainAxisAlignment: MainAxisAlignment.start,
  crossAxisAlignment: CrossAxisAlignment.start,
  children: [
    Padding(
      padding: const EdgeInsets.fromLTRB(20, 0, 0, 0),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            mainAxisAlignment: MainAxisAlignment.start,
            children: [
              Text(
                "공지",
                style: TextStyle(
                    color: Colors.black,
                    fontWeight: FontWeight.w700,
                    fontFamily: "AppleSDGothicNeo",
                    fontStyle: FontStyle.normal,
                    fontSize: 16.0),
              ),
              SizedBox(width: 5),
              StreamBuilder<QuerySnapshot>(
                stream: FirebaseFirestore.instance
                    .collection('Announcement')
                    .where('concertname', isEqualTo: widget.replay.title)
                    .snapshots(),
                builder: (context, snapshot) {
                  if (!snapshot.hasData) return CircularProgressIndicator();
                  return Text(
                    snapshot.data.docs.length.toString(),
                    style: TextStyle(
                        color: Colors.black26,
                        fontWeight: FontWeight.w500,
                        fontFamily: "AppleSDGothicNeo",
                        fontStyle: FontStyle.normal,
                        fontSize: 14.0),
                  );
                },
              ),
            ],
          ),
          SizedBox(
            height: 5,
          ),
          _buildBody(context),
        ],
      ),
    ),
    Divider(
      height: 30,
      thickness: 6,
      color: Color(0xffecedf4),
    ),
    Padding(
      padding: const EdgeInsets.only(left: 20, right: 20),
      child: Column(
        children: [
          Container(
            height: 50,
            child: Row(
              mainAxisAlignment: MainAxisAlignment.start,
              crossAxisAlignment: CrossAxisAlignment.center,
              children: [
                Text(
                  "팬 피드",
                  style: TextStyle(
                      color: Colors.black,
                      fontWeight: FontWeight.w700,
                      fontFamily: "AppleSDGothicNeo",
                      fontStyle: FontStyle.normal,
                      fontSize: 16.0),
                ),
                Spacer(),
                Text("최신순",
                    style: const TextStyle(
                        color: Colors.black26,
                        fontWeight: FontWeight.w300,
                        fontFamily: "AppleSDGothicNeo",
                        fontStyle: FontStyle.normal,
                        fontSize: 12.0),
                    textAlign: TextAlign.right),
                SizedBox(
                  child: Icon(
                    UniconIcon.iconchart,
                    color: Colors.black26,
                  ),
                ),
              ],
            ),
          ),
          Expanded(
              child: ListView(
            children: [
              CircleAvatar(
                backgroundImage: NetworkImage(
                    "https://lh3.googleusercontent.com/-5L9kDOItRJw/AAAAAAAAAAI/AAAAAAAAAAA/AMZuucmTNvDI3AljkDx1LMhuDaypX57yhA/s96-c/photo.jpg"),
              ),
              CircleAvatar(
                backgroundImage: NetworkImage(
                    "https://lh3.googleusercontent.com/-5L9kDOItRJw/AAAAAAAAAAI/AAAAAAAAAAA/AMZuucmTNvDI3AljkDx1LMhuDaypX57yhA/s96-c/photo.jpg"),
              ),
              CircleAvatar(
                backgroundImage: NetworkImage(
                    "https://lh3.googleusercontent.com/-5L9kDOItRJw/AAAAAAAAAAI/AAAAAAAAAAA/AMZuucmTNvDI3AljkDx1LMhuDaypX57yhA/s96-c/photo.jpg"),
              ),
            ],
          )),
        ],
      ),
    ),
  ],
);

```

}