Flutter ListTile 前导图片放置

我不确定如何将图像一直向左移动。我不想要那个领先的瓷砖空间。我可以用什么来实现这一点？

      ListTile(
          dense: true,
          onTap: () => Navigator.of(context).push(
            MaterialPageRoute(
              builder: (_) => UserAlert(
                uid: users[index]['uid'],
              ),
            ),
          ),
          tileColor: Colors.black,
          title: Text(
            users[index]['displayName'],
          ),
          leading: Positioned(
            child: Container(
              width: 50.0,
              height: 50.0,
              child: FadeInImage.assetNetwork(
                fit: BoxFit.cover,
                placeholder: 'assets/images/default-logo.png',
                image: users[index]['photoURL'],
              ),
            ),
          ),
        ),