reorderables 0.2.12

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reorderables #

pub package Awesome Flutter Buy Me A Coffee Donate

Various reorderable, a.k.a. drag and drop, Flutter widgets, including reorderable table, row, column, wrap, and sliver list, that make their children draggable and reorder them within the widget. Parent widget only need to provide an onReorder function that is invoked with the old and new indexes of child being reordered.

Thanks those who bought me cups of coffee. Really appreciated. I've been busy working on other projects and might not be able to resolve issues promptly. Sorry about that. Please reach out to me if you need commercial support. Nevertheless, do feel free to make pull requests. Switching between Python and Dart sometimes confused me. ;) #

Usage #

To use this package, add reorderables as a dependency in your pubspec.yaml file.

dependencies:
  reorderables:

And import the package in your code.

import 'package:reorderables/reorderables.dart';

Examples #

This package includes ReorderableSliverList, ReorderableTable, ReorderableWrap, ReorderableRow, and ReorderableColumn, which are reorderable versions of Flutter's SliverList, Table, Wrap, Row, and Column respectively.

ReorderableSliverList #

ReorderableSliverList behaves exactly like SliverList, but its children are draggable.

To make a SliverList reorderable, replace it with ReorderableSliverList and replace SliverChildListDelegate/SliverChildBuilderDelegate with ReorderableSliverChildListDelegate/ReorderableSliverChildBuilderDelegate. Do make sure that there's a ScrollController attached to the ScrollView that contains ReorderableSliverList, otherwise an error will be thrown when dragging list items.

class _SliverExampleState extends State<SliverExample> {
  List<Widget> _rows;

  @override
  void initState() {
    super.initState();
    _rows = List<Widget>.generate(50,
        (int index) => Text('This is sliver child $index', textScaleFactor: 2)
    );
  }

  @override
  Widget build(BuildContext context) {
    void _onReorder(int oldIndex, int newIndex) {
      setState(() {
        Widget row = _rows.removeAt(oldIndex);
        _rows.insert(newIndex, row);
      });
    }
    // Make sure there is a scroll controller attached to the scroll view that contains ReorderableSliverList.
    // Otherwise an error will be thrown.
    ScrollController _scrollController = PrimaryScrollController.of(context) ?? ScrollController();

    return CustomScrollView(
      // A ScrollController must be included in CustomScrollView, otherwise
      // ReorderableSliverList wouldn't work
      controller: _scrollController,
      slivers: <Widget>[
        SliverAppBar(
          expandedHeight: 210.0,
          flexibleSpace: FlexibleSpaceBar(
            title: Text('ReorderableSliverList'),
            background: Image.network(
              'https://upload.wikimedia.org/wikipedia/commons/thumb/6/68/Yushan'
                '_main_east_peak%2BHuang_Chung_Yu%E9%BB%83%E4%B8%AD%E4%BD%91%2B'
                '9030.png/640px-Yushan_main_east_peak%2BHuang_Chung_Yu%E9%BB%83'
                '%E4%B8%AD%E4%BD%91%2B9030.png'),
          ),
        ),
        ReorderableSliverList(
          delegate: ReorderableSliverChildListDelegate(_rows),
          // or use ReorderableSliverChildBuilderDelegate if needed
//          delegate: ReorderableSliverChildBuilderDelegate(
//            (BuildContext context, int index) => _rows[index],
//            childCount: _rows.length
//          ),
          onReorder: _onReorder,
        )
      ],
    );
  }
}

ReorderableSliverList Demo #

ReorderableTable #

The difference between table and list is that cells in a table are horizontally aligned, whereas in a list, each item can have children but they are not aligned with children in another item.

Making a row draggable requires cells to be contained in a single widget. This isn't achievable with Table or GridView widget since their children are laid out as cells of widget instead of rows of widget.

class _TableExampleState extends State<TableExample> {
  List<ReorderableTableRow> _itemRows;

  @override
  void initState() {
    super.initState();
    var data = [
      ['Alex', 'D', 'B+', 'AA', ''],
      ['Bob', 'AAAAA+', '', 'B', ''],
      ['Cindy', '', 'To Be Confirmed', '', ''],
      ['Duke', 'C-', '', 'Failed', ''],
      ['Ellenina', 'C', 'B', 'A', 'A'],
      ['Floral', '', 'BBB', 'A', 'A'],
    ];

    Widget _textWithPadding(String text) {
      return Padding(
        padding: EdgeInsets.symmetric(vertical: 4),
        child: Text(text, textScaleFactor: 1.1),
      );
    }

    _itemRows = data.map((row) {
      return ReorderableTableRow(
        //a key must be specified for each row
        key: ObjectKey(row),
        mainAxisSize: MainAxisSize.max,
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: <Widget>[
          _textWithPadding('${row[0]}'),
          _textWithPadding('${row[1]}'),
          _textWithPadding('${row[2]}'),
          _textWithPadding('${row[3]}'),
//          Text('${row[4]}'),
        ],
      );
    }).toList();
  }

  @override
  Widget build(BuildContext context) {
    var headerRow = ReorderableTableRow(
      mainAxisSize: MainAxisSize.max,
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
      children: [
        Text('Name', textScaleFactor: 1.5),
        Text('Math', textScaleFactor: 1.5),
        Text('Science', textScaleFactor: 1.5),
        Text('Physics', textScaleFactor: 1.5),
        Text('Sports', textScaleFactor: 1.5)
      ]
    );

    void _onReorder(int oldIndex, int newIndex) {
      setState(() {
        ReorderableTableRow row = _itemRows.removeAt(oldIndex);
        _itemRows.insert(newIndex, row);
      });
    }

    return ReorderableTable(
      header: headerRow,
      children: _itemRows,
      onReorder: _onReorder,
    );
  }
}

In a table, cells in each row are aligned on column basis with cells in other rows, whereas cells in a row of a list view don't align with other rows.

ReorderableTable Demo #

ReorderableWrap #

This widget can also limit the minimum and maximum amount of children in each run, on top of the size-based policy in Wrap's algorithm. See API references for more details. *Since v0.2.5, children of ReorderableWrap don't need to have a key explicitly specified.

class _WrapExampleState extends State<WrapExample> {
  final double _iconSize = 90;
  List<Widget> _tiles;

  @override
  void initState() {
    super.initState();
    _tiles = <Widget>[
      Icon(Icons.filter_1, size: _iconSize),
      Icon(Icons.filter_2, size: _iconSize),
      Icon(Icons.filter_3, size: _iconSize),
      Icon(Icons.filter_4, size: _iconSize),
      Icon(Icons.filter_5, size: _iconSize),
      Icon(Icons.filter_6, size: _iconSize),
      Icon(Icons.filter_7, size: _iconSize),
      Icon(Icons.filter_8, size: _iconSize),
      Icon(Icons.filter_9, size: _iconSize),
    ];
  }

  @override
  Widget build(BuildContext context) {
    void _onReorder(int oldIndex, int newIndex) {
      setState(() {
        Widget row = _tiles.removeAt(oldIndex);
        _tiles.insert(newIndex, row);
      });
    }

    var wrap = ReorderableWrap(
      spacing: 8.0,
      runSpacing: 4.0,
      padding: const EdgeInsets.all(8),
      children: _tiles,
      onReorder: _onReorder,
       onNoReorder: (int index) {
        //this callback is optional
        debugPrint('${DateTime.now().toString().substring(5, 22)} reorder cancelled. index:$index');
      },
      onReorderStarted: (int index) {
        //this callback is optional
        debugPrint('${DateTime.now().toString().substring(5, 22)} reorder started: index:$index');
      }
    );

    var column = Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: <Widget>[
        wrap,
        ButtonBar(
          alignment: MainAxisAlignment.start,
          children: <Widget>[
            IconButton(
              iconSize: 50,
              icon: Icon(Icons.add_circle),
              color: Colors.deepOrange,
              padding: const EdgeInsets.all(0.0),
              onPressed: () {
                var newTile = Icon(Icons.filter_9_plus, size: _iconSize);
                setState(() {
                  _tiles.add(newTile);
                });
              },
            ),
            IconButton(
              iconSize: 50,
              icon: Icon(Icons.remove_circle),
              color: Colors.teal,
              padding: const EdgeInsets.all(0.0),
              onPressed: () {
                setState(() {
                  _tiles.removeAt(0);
                });
              },
            ),
          ],
        ),
      ],
    );

    return SingleChildScrollView(
      child: column,
    );

  }
}

ReorderableWrap Demo #

Nested ReorderableWrap #

It is also possible to nest multiple levels of ReorderableWrap. See example/lib/nested_wrap_example.dart for complete example code.

class _NestedWrapExampleState extends State<NestedWrapExample> {
//  List<Widget> _tiles;
  Color _color;
  Color _colorBrighter;

  @override
  void initState() {
    super.initState();
    _color = widget.color ?? Colors.primaries[widget.depth % Colors.primaries.length];
    _colorBrighter = Color.lerp(_color, Colors.white, 0.6);
  }

  @override
  Widget build(BuildContext context) {
    void _onReorder(int oldIndex, int newIndex) {
      setState(() {
        widget._tiles.insert(newIndex, widget._tiles.removeAt(oldIndex));
      });
    }

    var wrap = ReorderableWrap(
      spacing: 8.0,
      runSpacing: 4.0,
      padding: const EdgeInsets.all(8),
      children: widget._tiles,
      onReorder: _onReorder
    );

    var buttonBar = Container(
      color: _colorBrighter,
      child: Row(
        mainAxisSize: MainAxisSize.min,
        mainAxisAlignment: MainAxisAlignment.start,
        children: <Widget>[
          IconButton(
            iconSize: 42,
            icon: Icon(Icons.add_circle),
            color: Colors.deepOrange,
            padding: const EdgeInsets.all(0.0),
            onPressed: () {
              setState(() {
                widget._tiles.add(
                  Card(
                    child: Container(
                      child: Text('${widget.valuePrefix}${widget._tiles.length}', textScaleFactor: 3 / math.sqrt(widget.depth + 1)),
                      padding: EdgeInsets.all((24.0 / math.sqrt(widget.depth + 1)).roundToDouble()),
                    ),
                    color: _colorBrighter,
                    elevation: 3,
                  )
                );
              });
            },
          ),
          IconButton(
            iconSize: 42,
            icon: Icon(Icons.remove_circle),
            color: Colors.teal,
            padding: const EdgeInsets.all(0.0),
            onPressed: () {
              setState(() {
                widget._tiles.removeAt(0);
              });
            },
          ),
          IconButton(
            iconSize: 42,
            icon: Icon(Icons.add_to_photos),
            color: Colors.pink,
            padding: const EdgeInsets.all(0.0),
            onPressed: () {
              setState(() {
                widget._tiles.add(NestedWrapExample(depth: widget.depth + 1, valuePrefix: '${widget.valuePrefix}${widget._tiles.length}.',));
              });
            },
          ),
          Text('Level ${widget.depth} / ${widget.valuePrefix}'),
        ],
      )
    );

    var column = Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        buttonBar,
        wrap,
      ]
    );

    return SingleChildScrollView(
      child: Container(child: column, color: _color,),
    );
  }
}

Nested ReorderableWrap Demo #

ReorderableColumn example #1 #

class _ColumnExample1State extends State<ColumnExample1> {
  List<Widget> _rows;

  @override
  void initState() {
    super.initState();
    _rows = List<Widget>.generate(50,
        (int index) => Text('This is row $index', key: ValueKey(index), textScaleFactor: 1.5)
    );
  }

  @override
  Widget build(BuildContext context) {
    void _onReorder(int oldIndex, int newIndex) {
      setState(() {
        Widget row = _rows.removeAt(oldIndex);
        _rows.insert(newIndex, row);
      });
    }

    return ReorderableColumn(
      header: Text('THIS IS THE HEADER ROW'),
      footer: Text('THIS IS THE FOOTER ROW'),
      crossAxisAlignment: CrossAxisAlignment.start,
      children: _rows,
      onReorder: _onReorder,
    );
  }
}

ReorderableColumn example #1 Demo #

ReorderableColumn example #2 #

class _ColumnExample2State extends State<ColumnExample2> {
  List<Widget> _rows;

  @override
  void initState() {
    super.initState();
    _rows = List<Widget>.generate(10,
        (int index) => Text('This is row $index', key: ValueKey(index), textScaleFactor: 1.5)
    );
  }

  @override
  Widget build(BuildContext context) {
    void _onReorder(int oldIndex, int newIndex) {
      setState(() {
        Widget row = _rows.removeAt(oldIndex);
        _rows.insert(newIndex, row);
      });
    }

    Widget reorderableColumn = IntrinsicWidth(
      child: ReorderableColumn(
        header: Text('List-like view but supports IntrinsicWidth'),
//        crossAxisAlignment: CrossAxisAlignment.start,
        children: _rows,
        onReorder: _onReorder,
      )
    );

    return Transform(
      transform: Matrix4.rotationZ(0),
      alignment: FractionalOffset.topLeft,
      child: Material(
        child: Card(child: reorderableColumn),
        elevation: 6.0,
        color: Colors.transparent,
        borderRadius: BorderRadius.zero,
      ),
    );
  }
}

ReorderableColumn example #2 Demo #

ReorderableRow #

See exmaple/lib/row_example.dart

ReorderableRow Demo #

Issues #

I've switched to Flutter channel stable from beta in order avoid compatibility issues. Supporting master or dev channels is not intended as they change frequently. Kindly make sure that you are using stable channel when submitting issues.

Support #

If you need commercial support, please reach out to me by sending me message on LinkedIn Hansheng

Otherwise, you can also support me by buying me a coffee or donate me via PayPal. Your support is very much appreciated. :)

Buy Me A Coffee or Donate or Say Thanks!

[0.2.12] - 22 June 2019.

  • Removed dependency of FlutterErrorDetails and other ErrorXXX classes.
  • Bugfix: needsLongPressDraggable had no default value.

[0.2.11+1] - 11 June 2019.

  • Flutter version dependency in pubspec

[0.2.11] - 11 June 2019.

  • ReorderableRow and ReorderableColumn: Set needsLongPressDraggable to false to use Draggable. Provide scrollController if use of external scroller controller is preferred.
  • Added onReorderStarted callback in ReorderableWrap
  • updated README

[0.2.10] - 10 June 2019.

  • Bugfix: DiagnosticsNode instead of String for newer version of Flutter

[0.2.9] - 16 May 2019.

  • Allows use of CupertinoApp

[0.2.8] - 16 May 2019.

  • Added onNoReorder callback

[0.2.7] - 11 May 2019.

  • Sliver's cross axis alignment defaults to start
  • Remove the use of global keys in reorderable sliver to allow nested sliver

[0.2.6] - 6 May 2019.

  • Bugfix: "width is null"

[0.2.5] - 3 May 2019.

  • Bugfix: ReorderableWrap supports nested wraps.
  • Improvement: children of ReorderableWrap don't have to have a key anymore.
  • Included nested ReorderableWrap example

[0.2.1] - 28 April 2019.

  • Bugfix: couldn't add/remove elements in ReorderableWrap.
  • Bugfix: added elements weren't draggable in ReorderableSliverList.
  • Merged pull request: flag to choose between long press draggable and the short one.

[0.2.0] - 5 March 2019.

  • Added ReorderableSliverList, ReorderableSliverChildBuilderDelegate, and ReorderableSliverChildListDelegate.
  • Bugfix: ReorderableFlex's animation.

[0.1.6] - 1 March 2019.

  • Updated API references and README.
  • Bugfix: made ReorderableTable's onReorder required.
  • Bugfix: corrected scrollDirection in ReorderableRow.

[0.1.5] - 26 February 2019.

  • Updated API references.

[0.1.4] - 25 February 2019.

  • Alignment bugfix.
  • Added column examples.

example/README.md

reorderables_example #

pub package Awesome Flutter Buy Me A Coffee Donate

Demonstrates how to use the reorderables package.

Getting Started #

This project is a starting point for using the reorderables package.

For help getting started with Flutter, view our online documentation, which offers tutorials, samples, guidance on mobile development, and a full API reference.

Demo #

ReorderableTable #

lib/table_example.dart

ReorderableWrap #

lib/wrap_example.dart

Nested ReorderableWrap #

lib/nested_wrap_example.dart

ReorderableColumn #

lib/column_example1.dart and lib/column_example2.dart

ReorderableRow #

lib/row_example.dart

ReorderableSliverList #

lib/sliver_example.dart

Use this package as a library

1. Depend on it

Add this to your package's pubspec.yaml file:


dependencies:
  reorderables: ^0.2.12

2. Install it

You can install packages from the command line:

with Flutter:


$ flutter pub get

Alternatively, your editor might support flutter pub get. Check the docs for your editor to learn more.

3. Import it

Now in your Dart code, you can use:


import 'package:reorderables/reorderables.dart';
  
Popularity:
Describes how popular the package is relative to other packages. [more]
93
Health:
Code health derived from static analysis. [more]
99
Maintenance:
Reflects how tidy and up-to-date the package is. [more]
100
Overall:
Weighted score of the above. [more]
96
Learn more about scoring.

We analyzed this package on Dec 5, 2019, and provided a score, details, and suggestions below. Analysis was completed with status completed using:

  • Dart: 2.6.1
  • pana: 0.12.21
  • Flutter: 1.9.1+hotfix.6

Platforms

Detected platforms: Flutter

References Flutter, and has no conflicting libraries.

Health suggestions

Fix lib/src/widgets/reorderable_sliver.dart. (-1 points)

Analysis of lib/src/widgets/reorderable_sliver.dart reported 2 hints:

line 372 col 27: The member 'positions' can only be used within instance members of subclasses of 'package:flutter/src/widgets/scroll_controller.dart'.

line 500 col 30: The member 'positions' can only be used within instance members of subclasses of 'package:flutter/src/widgets/scroll_controller.dart'.

Fix lib/src/widgets/reorderable_flex.dart. (-0.50 points)

Analysis of lib/src/widgets/reorderable_flex.dart reported 1 hint:

line 288 col 27: The member 'positions' can only be used within instance members of subclasses of 'package:flutter/src/widgets/scroll_controller.dart'.

Format lib/generated/i18n.dart.

Run flutter format to format lib/generated/i18n.dart.

Fix additional 4 files with analysis or formatting issues.

Additional issues in the following files:

  • lib/src/widgets/basic.dart (Run flutter format to format lib/src/widgets/basic.dart.)
  • lib/src/widgets/passthrough_overlay.dart (Run flutter format to format lib/src/widgets/passthrough_overlay.dart.)
  • lib/src/widgets/reorderable_table.dart (Run flutter format to format lib/src/widgets/reorderable_table.dart.)
  • lib/src/widgets/reorderable_wrap.dart (Run flutter format to format lib/src/widgets/reorderable_wrap.dart.)

Dependencies

Package Constraint Resolved Available
Direct dependencies
Dart SDK >=2.1.0 <3.0.0
flutter 0.0.0
Transitive dependencies
collection 1.14.11 1.14.12
meta 1.1.7 1.1.8
sky_engine 0.0.99
typed_data 1.1.6
vector_math 2.0.8
Dev dependencies
flutter_test