FlutterReorderableListView中如何在ListTiles之間創建空間

我有一個看起來像這樣的ReorderableListView：

我希望它在他的 ListTile 之間有空間，就像下面的ListView.separated一樣：

問題是我不想使用ListView.separated因為你不能用它拖放 ListTiles。

感謝您的幫助。

uj5u.com熱心網友回復：

您可以只用底部的填充將您的 listTile 包裝為“分隔符”，這可能并不理想，因為填充將是小部件的一部分，在拖動時會可見。

import 'package:flutter/material.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  static const String _title = 'Flutter Code Sample';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: _title,
      home: Scaffold(
        appBar: AppBar(title: const Text(_title)),
        body: const MyStatefulWidget(),
      ),
    );
  }
}

class MyStatefulWidget extends StatefulWidget {
  const MyStatefulWidget({Key? key}) : super(key: key);

  @override
  State<MyStatefulWidget> createState() => _MyStatefulWidgetState();
}

class _MyStatefulWidgetState extends State<MyStatefulWidget> {
  final List<int> _items = List<int>.generate(50, (int index) => index);

  @override
  Widget build(BuildContext context) {
    final ColorScheme colorScheme = Theme.of(context).colorScheme;
    final Color oddItemColor = colorScheme.primary.withOpacity(0.05);
    final Color evenItemColor = colorScheme.primary.withOpacity(0.15);

    return ReorderableListView(
      padding: const EdgeInsets.symmetric(horizontal: 40),
      children: <Widget>[
        for (int index = 0; index < _items.length; index  )
          Padding(
              key: Key('$index'),
              padding: const EdgeInsets.only(bottom: 4),
              child: ListTile(
                tileColor: _items[index].isOdd ? oddItemColor : evenItemColor,
                title: Text('Item ${_items[index]}'),
              )),
      ],
      onReorder: (int oldIndex, int newIndex) {
        setState(() {
          if (oldIndex < newIndex) {
            newIndex -= 1;
          }
          final int item = _items.removeAt(oldIndex);
          _items.insert(newIndex, item);
        });
      },
    );
  }
}

使用 ReorderableListView 似乎無法將空間添加為不可重新排序的小部件，即使添加將 ListTiles 與 AbsorbPointer 交錯的虛擬專案仍然會使它們可重新排序。所以上面的方法至少是可行的

      children: <Widget>[
        for (int index = 0; index < _items.length; index  )
          if (index.isOdd)
            ListTile(
              key: Key('$index'),
              tileColor: _items[index].isOdd ? oddItemColor : evenItemColor,
              title: Text('Item ${_items[index]}'),
            )
          else if (index.isEven)
            AbsorbPointer(
              key: Key('$index'),
              child: SizedBox.square(
                key: Key('$index'),
                dimension: 40,
              ),
            ),
      ],

uj5u.com熱心網友回復：

將您的 ListTile 包裝在一列中，并使用 SizedBox 分隔串列項。在列中使用鍵，而不是在 ListTile 中。

import 'package:flutter/material.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  static const String _title = 'Flutter Code Sample';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: _title,
      home: Scaffold(
        appBar: AppBar(title: const Text(_title)),
        body: const MyStatefulWidget(),
      ),
    );
  }
}

class MyStatefulWidget extends StatefulWidget {
  const MyStatefulWidget({Key? key}) : super(key: key);

  @override
  State<MyStatefulWidget> createState() => _MyStatefulWidgetState();
}

class _MyStatefulWidgetState extends State<MyStatefulWidget> {
  final List<int> _items = List<int>.generate(50, (int index) => index);

  @override
  Widget build(BuildContext context) {
    final ColorScheme colorScheme = Theme.of(context).colorScheme;
    final Color oddItemColor = colorScheme.primary.withOpacity(0.05);
    final Color evenItemColor = colorScheme.primary.withOpacity(0.15);

    return ReorderableListView(
      padding: const EdgeInsets.symmetric(horizontal: 40),
      children: <Widget>[
        for (int index = 0; index < _items.length; index  )
          Column(
            key: Key('$index'),
            children: [
              ListTile(
                tileColor: _items[index].isOdd ? oddItemColor : evenItemColor,
                title: Text('Item ${_items[index]}'),
              ),
              SizedBox(
                height: 5,
              ),
            ],
          ),
      ],
      onReorder: (int oldIndex, int newIndex) {
        setState(() {
          if (oldIndex < newIndex) {
            newIndex -= 1;
          }
          final int item = _items.removeAt(oldIndex);
          _items.insert(newIndex, item);
        });
      },
    );
  }
}

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