如何为小部件 Flutter 添加垂直间距
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【中文标题】如何为小部件 Flutter 添加垂直间距【英文标题】：How to add vertical spacing to widgets Flutter 【发布时间】：2021-08-08 03:18:39 【问题描述】：我这里有一段代码，它构成了登录和注册屏幕的主体。一切都在我想要的位置，但我想把它们隔开一点。两个输入字段，标题、副标题、按钮和文本按钮在垂直方向上靠得太近。 我尝试使用 mainaxisalignment.spacebetween，但出现约束错误，之后屏幕上的所有内容都消失了，但背景除外。
注册和登录屏幕使用的正文：
Widget build(BuildContext context)
return Scaffold(
backgroundColor: Colors.transparent,
body: Container(
decoration: BoxDecoration(
gradient: LinearGradient(
begin: Alignment.topLeft,
end: Alignment.bottomLeft,
colors: [Color(0xFF1F1F1F), Color(0xFF1F1F1F)],
),
image: DecorationImage(
image: AssetImage("lib/assets/images/register.png"),
alignment: Alignment.topCenter,
),
),
child: Stack(
children: [
Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage('lib/assets/images/bottomleft.png'),
alignment: Alignment.bottomLeft,
),
),
),
Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage('lib/assets/images/toptop.png'),
alignment: Alignment.topRight,
),
),
),
Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage('lib/assets/images/topbig.png'),
alignment: Alignment.topCenter,
repeat: ImageRepeat.repeat),
),
),
Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage('lib/assets/images/top.png'),
alignment: Alignment.topCenter,
repeat: ImageRepeat.repeatX),
),
),
Padding(
padding:
const EdgeInsets.symmetric(horizontal: 25, vertical: 250),
child: ListView(
children: [
if (onBackPressed == null) verticalSpaceLarge,
if (onBackPressed != null) verticalSpaceRegular,
if (onBackPressed != null)
IconButton(
padding: EdgeInsets.zero,
onPressed: onBackPressed,
alignment: Alignment.centerLeft,
icon: Icon(
Icons.arrow_back_ios,
color: Colors.black,
),
),
Center(
child: Text(
title!,
style: TextStyle(
color: Colors.white,
fontSize: 30.0,
fontWeight: FontWeight.bold,
fontFamily: 'Montserrat',
),
),
),
Align(
alignment: Alignment.center,
child: SizedBox(
child: Center(
child: Text(
subtitle!,
style: ktsMediumGreyBodyText,
),
),
),
),
form!,
if (onForgotPassword != null)
Align(
alignment: Alignment.centerRight,
child: GestureDetector(
onTap: onForgotPassword,
child: Center(
child: Text(
'Forgot Password?',
style: ktsMediumGreyBodyText.copyWith(),
),
),
),
),
if (validationMessage != null)
Center(
child: Text(
validationMessage!,
style: TextStyle(
color: Colors.red, fontSize: kBodyTextSize),
),
),
if (validationMessage != null) verticalSpaceRegular,
GestureDetector(
onTap: onMainButtonTapped,
child: Container(
width: double.infinity,
height: 50,
alignment: Alignment.center,
decoration: BoxDecoration(
color: kcPrimaryColor,
borderRadius: BorderRadius.circular(8),
),
child: busy!
? CircularProgressIndicator(
valueColor: AlwaysStoppedAnimation(Colors.white),
)
: Text(
mainButtonTitle!,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 14),
),
),
),
if (onCreateAccountTapped != null)
GestureDetector(
onTap: onCreateAccountTapped,
child: Center(
child: Column(
children: [
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text(
"Don\'t have an account?",
style: TextStyle(color: Colors.white),
),
Text(
"SIGN UP",
style: TextStyle(color: kcPrimaryColor),
),
],
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text(
"OR SIGN IN WITH",
style: TextStyle(color: kcMediumGreyColor),
),
],
),
],
),
),
),
if (showTermsText!)
Center(
child: Text(
"By signing up you agree to our terms, conditions and privacy policy",
style: ktsMediumGreyBodyText,
textAlign: TextAlign.center,
),
),
],
),
),
],
),
),
);
登录屏幕：
Widget build(BuildContext context)
return ViewModelBuilder<LoginScreenModel>.reactive(
builder: (context, model, child) => Scaffold(
body: AuthenticationLayout(
busy: model.isBusy,
onCreateAccountTapped: () ,
//validationMessage: model.validationMessage,
title: 'SIGN IN',
subtitle: 'please fill the form below',
mainButtonTitle: 'SIGN IN',
form: Column(
children: [
TextField(
decoration: InputDecoration(
hintText: 'Username',
hintStyle: TextStyle(color: Colors.white),
prefixIcon: const Icon(
Icons.person,
color: Colors.white,
),
),
),
TextField(
decoration: InputDecoration(
hintText: 'Password',
hintStyle: TextStyle(color: Colors.white),
prefixIcon: const Icon(
Icons.lock,
color: Colors.white,
),
),
),
],
),
onForgotPassword: () ,
),
),
viewModelBuilder: () => LoginScreenModel(),
);
【问题讨论】：
【参考方案1】： Column(
children: <Widget>[
FirstWidget(),
SizedBox(height: 100),
SecondWidget(),
],
),
【讨论】：
【参考方案2】：您应该在两个小部件之间添加 SizedBox()，或为您的小部件设置填充，或者您也使用容器，如下所示：
使用 SizedBox()
Column(
children:[
Widget 1(),
SizedBox(height:10),
Widget 2(),
SizedBox(height:10),
Widget 3(),
],
),
使用 Padding()
Column(
children:[
Padding(
padding:EdgeInsets.all(8.0)
child: Widget 1(),
),
Padding(
padding:EdgeInsets.all(8.0)
child: Widget 2(),
),
Padding(
padding:EdgeInsets.all(8.0)
child: Widget 3(),
),
],
),
使用 Container()
Column(
children:[
Container(
padding:EdgeInsets.all(8.0)
child: Widget 1(),
),
Container(
padding:EdgeInsets.all(8.0)
child: Widget 2(),
),
Container(
padding:EdgeInsets.all(8.0)
child: Widget 3(),
),
],
),
您应该在您的选择上使用填充，例如：
EdgeInsets.all(8.0),
EdgeInsets.only(left:8.0,top:8.0,right:8.0,bottom:8.0),
EdgeInsets.symmetric(vertical: 8.0,horizontal:8.0),
【讨论】：
【参考方案3】：您可以在组件之间添加一些 SizedBox() 或设置边距。
【讨论】：
【参考方案4】：使用 SizedBox 小部件为小部件添加垂直间距。 例如
SizedBox(height: 16),
【讨论】：
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