您可以使用Padding来包装每个子部件，然后设置Padding的顶部或底部。

如果你不想写很多相同的数字，你可以这样写:

Column(
  children: [
    child1, 
    child2, 
    ..., 
    childN
  ].map((e) => Padding(padding: EdgeInsets.only(top: 10), child: e)).toList()
);

如果在列、行、listView等中有太多的子元素，并且必须在应用程序的许多地方执行相同的操作，那么添加多个大小的框将变得乏味。

你可以使用下面的utils来封装添加这些大小的盒子的逻辑:

List<Widget> addHorizontalSpaceBetweenElements(double space, List<Widget> widgets) {
  return _addSpaceBetweenElements(widgets, () => SizedBox(width: space));
}

List<Widget> addVerticalSpaceBetweenElements(double space, List<Widget> widgets) {
  return _addSpaceBetweenElements(widgets, () => SizedBox(height: space));
}

List<Widget> _addSpaceBetweenElements(List<Widget> widgets, ValueGetter<SizedBox> sizedBoxGetter) {
  if (widgets.isEmpty || widgets.length == 1) {
    return widgets;
  }
  List<Widget> spacedWidgets = [widgets.first];
  for (var i = 1; i < widgets.length - 1; i++) {
    spacedWidgets.add(sizedBoxGetter());
    spacedWidgets.add(widgets[i]);
  }
  spacedWidgets.add(sizedBoxGetter());
  spacedWidgets.add(widgets.last);
  return spacedWidgets;
}

你可以这样使用它们:

Column(
  children: addVerticalSpaceBetweenElements(5, [
    Text(),
    Text(),
  Row(children: addHorizontalSpaceBetweenElements(5, [
    Text(),
    Text(),
  ])),
  ]));

在这种情况下，大小框将不起作用，手机处于横向模式。

body: Column(
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: <Widget>[
        Expanded(
           child: Container(
            margin: EdgeInsets.all(15.0),
            decoration: BoxDecoration(
              color: Color(0xFF1D1E33),
              borderRadius: BorderRadius.circular(10.0),
            ),
          ),
        ),
        Expanded(
           child: Container(
            margin: EdgeInsets.all(15.0),
            decoration: BoxDecoration(
              color: Color(0xFF1D1E33),
              borderRadius: BorderRadius.circular(10.0),
            ),
          ),
        ),
        Expanded(
           child: Container(
            margin: EdgeInsets.all(15.0),
            decoration: BoxDecoration(
              color: Color(0xFF1D1E33),
              borderRadius: BorderRadius.circular(10.0),
            ),
          ),
        ),
      ],
     )

你可以试试这个:

import 'package:flutter/material.dart';

class CustomColumn extends Column {
  CustomColumn({
    Key? key,
    MainAxisAlignment mainAxisAlignment = MainAxisAlignment.start,
    MainAxisSize mainAxisSize = MainAxisSize.max,
    CrossAxisAlignment crossAxisAlignment = CrossAxisAlignment.center,
    TextDirection? textDirection,
    VerticalDirection verticalDirection = VerticalDirection.down,
    TextBaseline? textBaseline,
    List children = const [],
    EdgeInsetsGeometry? rowPadding,
  }) : super(
          children: children.map((e) => Padding(padding : rowPadding ?? EdgeInsets.only(bottom:12), child : e)).toList(),
          key: key,
          mainAxisAlignment: mainAxisAlignment,
          mainAxisSize: mainAxisSize,
          crossAxisAlignment: crossAxisAlignment,
          textDirection: textDirection,
          verticalDirection: verticalDirection,
          textBaseline: textBaseline,
        );
}

并调用

CustomColumn(children: [
                    item1,
                    item2,
                    item3,
                  ])

我也希望在Flutter中有一些内置的方法来做到这一点。就像一个参数，你可以传递给列或行。有时你不希望每个元素都有填充，但希望元素之间有空格。特别是如果你有两个以上的孩子，写这样的东西有点乏味

const double gap = 10;
return Column(
  children: [
    Text('Child 1'),
    SizedBox(height: gap),
    Text('Child 2'),
    SizedBox(height: gap),
    Text('Child 3'),
    SizedBox(height: gap),
    Text('Child 4'),
  ],
);

然而，我想出了一个快速(不完美)的解决方案:

在你的项目中添加这个(只有一次):

extension ListSpaceBetweenExtension on List<Widget> {
  List<Widget> withSpaceBetween({double? width, double? height}) => [
    for (int i = 0; i < this.length; i++)
      ...[
        if (i > 0)
          SizedBox(width: width, height: height),
        this[i],
      ],
  ];
}

从现在开始，只要你有行或列，你就可以写

Column(
  children: [
    Text('Child 1'),
    Text('Child 2'),
    Text('Child 3'),
    Text('Child 4'),
  ].withSpaceBetween(height: 10),
),

当使用Row时，你必须用width替换height。

只需要像这样用填充物把它包起来:

Column(
  children: <Widget>[
  Padding(
    padding: EdgeInsets.all(8.0),
    child: Text('Hello World!'),
  ),
  Padding(
    padding: EdgeInsets.all(8.0),
    child: Text('Hello World2!'),
  )
]);

你也可以使用Container(padding…)或SizeBox(height: x.x)。最后一种是最常见的，但这取决于你想如何管理小部件的空间，如果空间确实是小部件的一部分，我喜欢使用填充，例如列表使用sizebox。