小编Sal*_*ine的帖子

我正在尝试在 CircleAvatar 小部件的下拉列表中显示这些头像。但是，图像在 CircleAvatar 中不正确，如下图所示。我尝试裁剪它们并更改大小，但它仍然放大到图像中。任何帮助，将不胜感激。下面是我用来在下拉列表中显示的头像列表的代码。

   List<AvatarItem> avatars = <AvatarItem>[
    const AvatarItem(avatarString: 'female_avatar_1.png', avatar: Center(
      child: Padding(
        padding: const EdgeInsets.all(3.0),
        child: CircleAvatar(backgroundImage: AssetImage('assets/female_avatar_1.png'), backgroundColor: Colors.white, radius: 30.0,),
      ),
    )),
    const AvatarItem(avatarString: 'male_avatar_1.png', avatar: Center(
      child: Padding(
        padding: const EdgeInsets.all(3.0),
        child: CircleAvatar(backgroundImage: AssetImage('assets/male_avatar_1.png'), backgroundColor: Colors.white, radius: 30.0,),
      ),
    )),
    const AvatarItem(avatarString: 'female_avatar_2.png', avatar: Center(
      child: Padding(
        padding: const EdgeInsets.all(3.0),
        child: CircleAvatar(backgroundImage: AssetImage('assets/female_avatar_2.png'), backgroundColor: Colors.white, radius: 30.0,),
      ),
    )),
    const AvatarItem(avatarString: 'male_avatar_2.png', avatar: Center(
      child: Padding(
        padding: const EdgeInsets.all(3.0),
        child: CircleAvatar(backgroundImage: AssetImage('assets/male_avatar_2.png'), backgroundColor: …

当我添加 SingleChildScrollView 小部件时，整个容器就会上升，底部有一个白色背景框，如屏幕截图所示。我尝试删除包括底部在内的整个填充，但没有任何改变。我真的不知道该怎么做。任何帮助，将不胜感激。屏幕截图

Widget build(BuildContext context) {

final bottom = MediaQuery.of(context).viewInsets.bottom;
// If we're loading then return the loading screen, otherwise the
// scaffold with the register screen
return loading ? Loading() : Scaffold (
  resizeToAvoidBottomInset: false,
  resizeToAvoidBottomPadding: false,
  body: SingleChildScrollView(
    child: Container (
      padding: EdgeInsets.fromLTRB(60.0, 0, 60, bottom),
      decoration: BoxDecoration(
        image: DecorationImage(
          image: AssetImage('assets/register_background.png'),
          fit: BoxFit.fill,
        ),
      ),
      child: Form (
        key: _formKey,
        child: Column (
          mainAxisAlignment: MainAxisAlignment.start,
          children: <Widget>[
            SizedBox(height: MediaQuery.of(context).size.height * 0.04),
            Image.asset('assets/logo.png'),
            SizedBox(height: MediaQuery.of(context).size.height * …

class _SelectMedChallengeState extends State<SelectMedChallenge> {

List<String> categoryList;
@override
void initState() {
  super.initState();
  setState(() {
    categoryList = DatabaseService().getCategoryList();
  });
  print(categoryList);
}

createAlertDialog(BuildContext context){
return showDialog(context: context, builder: (context){
  return AlertDialog(
    content: Center (
      child: Column(
        mainAxisSize: MainAxisSize.min,
        children: <Widget>[
          Text(
            'CATEGORY',
            style: TextStyle(
              fontFamily: 'MuseoSans',
              fontSize: 24.0,
            ),
          ),
          SizedBox(height: 20.0,),
          ButtonTheme (
            minWidth: 288.0,
            height: 109.0,
            buttonColor: Color.fromARGB(255, 102, 199, 227),
            child: RaisedButton (
              shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(10.0),
                side: BorderSide(
                  color: Colors.transparent,
                ),
              ),
              child: Text(
                'BEGINNER',
                style: TextStyle(
                  color: …