# Multi Select Flutter [![Pub Version](https://img.shields.io/pub/v/multi_select_flutter.svg)](https://pub.dev/packages/multi_select_flutter) Multi Select Flutter is a package for creating multi-select widgets in a variety of ways. |

_Dialog |

_BottomSheet |

_ChoiceChip | | :---: | :---: | :---: | ## Features - Supports FormField features like validator. - Neutral default design. - Dialog, BottomSheet, or ChoiceChip style widgets. - Make your multi select `searchable` for larger lists. ## Usage ### MultiSelectDialogField / MultiSelectBottomSheetField

These widgets provide an InkWell button which open the dialog or bottom sheet and are equipped with FormField features. You can customize it using the provided parameters. To store the selected values, you can use the `onConfirm` parameter. You could also use `onSelectionChanged` for this. By default these widgets render a MultiSelectChipDisplay below the field. This can be overridden with the `chipDisplay` parameter or removed completely by using `chipDisplay: MultiSelectChipDisplay.none()`. ```dart MultiSelectDialogField( items: _animals.map((e) => MultiSelectItem(e, e.name)).toList(), listType: MultiSelectListType.CHIP, onConfirm: (values) { _selectedAnimals = values; }, ), ``` ### MultiSelectDialog / MultiSelectBottomSheet

If you prefer to create your own button for opening the dialog or bottom sheet, you may do so and then make a call to a function like this: `MultiSelectDialog` can be used in the builder of `showDialog()`. ```dart void _showMultiSelect(BuildContext context) async { await showDialog( context: context, builder: (ctx) { return MultiSelectDialog( items: _items, initialValue: _selectedAnimals, onConfirm: (values) {...}, ); }, ); } ``` `MultiSelectBottomSheet` can be used in the builder of `showModalBottomSheet()`. ```dart void _showMultiSelect(BuildContext context) async { await showModalBottomSheet( isScrollControlled: true, // required for min/max child size context: context, builder: (ctx) { return MultiSelectBottomSheet( items: _items, initialValue: _selectedAnimals, onConfirm: (values) {...}, maxChildSize: 0.8, ); }, ); } ``` ### MultiSelectChipDisplay

To display the selected items, this widget can be used alongside your own button or it can be specified as a `chipDisplay` parameter of widgets like `MultiSelectDialogField`. You can also remove items from the source list in the onTap function. ```dart MultiSelectChipDisplay( items: _selectedAnimals.map((e) => MultiSelectItem(e, e)).toList(), onTap: (value) { setState(() { _selectedAnimals.remove(value); }); }, ), ``` A MultiSelectChipDisplay that is part of a MultiSelectDialogField still renders outside the BoxDecoration of the MultiSelectDialogField as seen here:

If you want to encapsulate the MultiSelectChipDisplay, wrap the MultiSelectDialogField in a Container and apply the decoration to that instead: ```dart Container( decoration: BoxDecoration(...), child: MultiSelectDialogField( items: _items, chipDisplay: MultiSelectChipDisplay(...), ), ), ```

### MultiSelectChipField

This widget is similar to MultiSelectChipDisplay, except these chips are the primary interface for selecting items. ```dart MultiSelectChipField( items: _items, icon: Icon(Icons.check), onTap: (values) { _selectedAnimals = values; }, ), ``` #### Using `itemBuilder` to create custom items: ```dart MultiSelectChipField( items: _items, key: _multiSelectKey, validator: (values) {...} itemBuilder: (item, state) { // return your custom widget here return InkWell( onTap: () { _selectedAnimals.contains(item.value) ? _selectedAnimals.remove(item.value) : _selectedAnimals.add(item.value); state.didChange(_selectedAnimals); _multiSelectKey.currentState.validate(); }, child: Text(item.value.name), ); }, ), ``` The `itemBuilder` param takes a function that will create a widget for each of the provided `items`. In order to use validator and other FormField features with custom widgets, you must call `state.didChange(_updatedList)` any time the list of selected items is updated. #### Using `scrollControl` to auto scroll: ```dart MultiSelectChipField( items: _items, scrollControl: (controller) { _startAnimation(controller); }, ) // waits 5 seconds, scrolls to end slow, then back fast void _startAnimation(ScrollController controller) { // when using more than one animation, use async/await Future.delayed(const Duration(milliseconds: 5000), () async { await controller.animateTo( controller.position.maxScrollExtent, duration: Duration(milliseconds: 8000), curve: Curves.linear); await controller.animateTo( controller.position.minScrollExtent, duration: Duration(milliseconds: 1250), curve: Curves.fastLinearToSlowEaseIn); }); } ``` ## Contributing Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

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