expand image in circle avatar flutter code example

Example 1: circle avatar from image asset flutter

CircleAvatar(
    radius: 16.0,
    child: ClipRRect(
        child: Image.asset('profile-generic.png'),
        borderRadius: BorderRadius.circular(50.0),
    ),
),

Example 2: how to make an image contained in circle avatar in flutter

CircleAvatar(
                radius: 30.0,
                backgroundImage:
                    NetworkImage("${snapshot.data.hitsList[index].previewUrl}"),
                backgroundColor: Colors.transparent,
              )