Adding a Chip to a Material TextField - dart

Question

Say we created a Chip object and TextField object like below. How do you add a Chip to the inside of the TextField?
new Chip(
label: new Text('Peyton Smith'),
)
new TextField(
)
Is it possible to combine them to get something like in the Material spec where typing in something into a Material TextField adds a Chip?

Answer 1

What you are looking for was actually provided in the comment.
Here is a simple implementation using InputChip:
InputChip(
avatar: CircleAvatar(
backgroundColor: Colors.grey.shade800,
child: Text('AB'),
),
label: Text('Aaron Burr'),
onPressed: () {
print('I am the one thing in life.');
}
)
A material design input chip.
Input chips represent a complex piece of information, such as an
entity (person, place, or thing) or conversational text, in a compact
form.
Input chips can be made selectable by setting
onSelected,
deletable by setting
onDeleted,
and pressable like a button with
onPressed.
They have a
label,
and they can have a leading icon (see
avatar)
and a trailing icon
(deleteIcon).
Colors and padding can be customized.
Here is my simple interpretation of InputChip:
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
Align(
alignment: Alignment.centerLeft,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: _toContainer(),
),
),
Divider(
color: Colors.blueGrey,
height: 10.0,
),
Align(
alignment: Alignment.centerLeft,
child: _subjectContainer(),
),
Divider(
color: Colors.blueGrey,
height: 10.0,
),
Align(
alignment: Alignment.centerLeft,
child: _messageContainer(),
),
],
),
), // This trailing comma makes auto-formatting nicer for build methods.
);
}
Widget _messageContainer() {
return Padding(
padding: const EdgeInsets.all(8.0),
child: Container(
child: Text(
'Message',
style: TextStyle(color: Colors.black, fontSize: 18.0),
),
),
);
}
Widget _toContainer() {
return Wrap(
spacing: 5.0,
children: <Widget>[
Padding(
padding: const EdgeInsets.only(top: 8.0, right: 8.0),
child: Container(
child: Text(
'To',
style: TextStyle(color: Colors.black, fontSize: 18.0),
),
),
),
Container(
child: _profileChips("Scott Hill",
"https://images.unsplash.com/photo-1507003211169-0a1dd7228f2d?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=634&q=80"),
),
],
);
}
Widget _subjectContainer() {
return Padding(
padding: const EdgeInsets.all(8.0),
child: Container(
child: Text(
'Subject',
style: TextStyle(color: Colors.black, fontSize: 18.0),
),
),
);
}
Widget _profileChips(String myName, String myImage) {
return Material(
child: InputChip(
avatar: CircleAvatar(
backgroundColor: Colors.blueGrey,
child: Container(
decoration: BoxDecoration(
shape: BoxShape.circle,
image: DecorationImage(
fit: BoxFit.fill,
image: NetworkImage(myImage),
)),
),
),
label: Text(myName),
labelStyle: TextStyle(
color: Colors.black, fontSize: 14.0, fontWeight: FontWeight.bold),
onPressed: () {},
onDeleted: () {},
),
);
}
}
Output:
And for a fully functional example, I've tested the answer in here.
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
// See: https://twitter.com/shakil807/status/1042127387515858949
// https://github.com/pchmn/MaterialChipsInput/tree/master/library/src/main/java/com/pchmn/materialchips
// https://github.com/BelooS/ChipsLayoutManager
void main() => runApp(ChipsDemoApp());
class ChipsDemoApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData(
primaryColor: Colors.indigo,
accentColor: Colors.pink,
),
home: DemoScreen(),
);
}
}
class DemoScreen extends StatefulWidget {
#override
_DemoScreenState createState() => _DemoScreenState();
}
class _DemoScreenState extends State<DemoScreen> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Material Chips Input'),
),
body: Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: TextField(
decoration: const InputDecoration(hintText: 'normal'),
),
),
Expanded(
child: Padding(
padding: const EdgeInsets.all(8.0),
child: ChipsInput<AppProfile>(
decoration: InputDecoration(
prefixIcon: Icon(Icons.search), hintText: 'Profile search'),
findSuggestions: _findSuggestions,
onChanged: _onChanged,
chipBuilder: (BuildContext context,
ChipsInputState<AppProfile> state, AppProfile profile) {
return InputChip(
key: ObjectKey(profile),
label: Text(profile.name),
avatar: CircleAvatar(
backgroundImage: NetworkImage(profile.imageUrl),
),
onDeleted: () => state.deleteChip(profile),
onSelected: (_) => _onChipTapped(profile),
materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
);
},
suggestionBuilder: (BuildContext context,
ChipsInputState<AppProfile> state, AppProfile profile) {
return ListTile(
key: ObjectKey(profile),
leading: CircleAvatar(
backgroundImage: NetworkImage(profile.imageUrl),
),
title: Text(profile.name),
subtitle: Text(profile.email),
onTap: () => state.selectSuggestion(profile),
);
},
),
),
),
],
),
);
}
void _onChipTapped(AppProfile profile) {
print('$profile');
}
void _onChanged(List<AppProfile> data) {
print('onChanged $data');
}
Future<List<AppProfile>> _findSuggestions(String query) async {
if (query.length != 0) {
return mockResults.where((profile) {
return profile.name.contains(query) || profile.email.contains(query);
}).toList(growable: false);
} else {
return const <AppProfile>[];
}
}
}
// -------------------------------------------------
const mockResults = <AppProfile>[
AppProfile('Stock Man', 'stock#man.com',
'https://d2gg9evh47fn9z.cloudfront.net/800px_COLOURBOX4057996.jpg'),
AppProfile('Paul', 'paul#google.com',
'https://mbtskoudsalg.com/images/person-stock-image-png.png'),
AppProfile('Fred', 'fred#google.com',
'https://media.istockphoto.com/photos/feeling-great-about-my-corporate-choices-picture-id507296326'),
AppProfile('Bera', 'bera#flutter.io',
'https://upload.wikimedia.org/wikipedia/commons/7/7c/Profile_avatar_placeholder_large.png'),
AppProfile('John', 'john#flutter.io',
'https://upload.wikimedia.org/wikipedia/commons/7/7c/Profile_avatar_placeholder_large.png'),
AppProfile('Thomas', 'thomas#flutter.io',
'https://upload.wikimedia.org/wikipedia/commons/7/7c/Profile_avatar_placeholder_large.png'),
AppProfile('Norbert', 'norbert#flutter.io',
'https://upload.wikimedia.org/wikipedia/commons/7/7c/Profile_avatar_placeholder_large.png'),
AppProfile('Marina', 'marina#flutter.io',
'https://upload.wikimedia.org/wikipedia/commons/7/7c/Profile_avatar_placeholder_large.png'),
];
class AppProfile {
final String name;
final String email;
final String imageUrl;
const AppProfile(this.name, this.email, this.imageUrl);
#override
bool operator ==(Object other) =>
identical(this, other) ||
other is AppProfile &&
runtimeType == other.runtimeType &&
name == other.name;
#override
int get hashCode => name.hashCode;
#override
String toString() {
return 'Profile{$name}';
}
}
// -------------------------------------------------
typedef ChipsInputSuggestions<T> = Future<List<T>> Function(String query);
typedef ChipSelected<T> = void Function(T data, bool selected);
typedef ChipsBuilder<T> = Widget Function(
BuildContext context, ChipsInputState<T> state, T data);
class ChipsInput<T> extends StatefulWidget {
const ChipsInput({
Key key,
this.decoration = const InputDecoration(),
#required this.chipBuilder,
#required this.suggestionBuilder,
#required this.findSuggestions,
#required this.onChanged,
this.onChipTapped,
}) : super(key: key);
final InputDecoration decoration;
final ChipsInputSuggestions findSuggestions;
final ValueChanged<List<T>> onChanged;
final ValueChanged<T> onChipTapped;
final ChipsBuilder<T> chipBuilder;
final ChipsBuilder<T> suggestionBuilder;
#override
ChipsInputState<T> createState() => ChipsInputState<T>();
}
class ChipsInputState<T> extends State<ChipsInput<T>>
implements TextInputClient {
static const kObjectReplacementChar = 0xFFFC;
Set<T> _chips = Set<T>();
List<T> _suggestions;
int _searchId = 0;
FocusNode _focusNode;
TextEditingValue _value = TextEditingValue();
TextInputConnection _connection;
String get text => String.fromCharCodes(
_value.text.codeUnits.where((ch) => ch != kObjectReplacementChar),
);
bool get _hasInputConnection => _connection != null && _connection.attached;
void requestKeyboard() {
if (_focusNode.hasFocus) {
_openInputConnection();
} else {
FocusScope.of(context).requestFocus(_focusNode);
}
}
void selectSuggestion(T data) {
setState(() {
_chips.add(data);
_updateTextInputState();
_suggestions = null;
});
widget.onChanged(_chips.toList(growable: false));
}
void deleteChip(T data) {
setState(() {
_chips.remove(data);
_updateTextInputState();
});
widget.onChanged(_chips.toList(growable: false));
}
#override
void initState() {
super.initState();
_focusNode = FocusNode();
_focusNode.addListener(_onFocusChanged);
}
void _onFocusChanged() {
if (_focusNode.hasFocus) {
_openInputConnection();
} else {
_closeInputConnectionIfNeeded();
}
setState(() {
// rebuild so that _TextCursor is hidden.
});
}
#override
void dispose() {
_focusNode?.dispose();
_closeInputConnectionIfNeeded();
super.dispose();
}
void _openInputConnection() {
if (!_hasInputConnection) {
_connection = TextInput.attach(this, TextInputConfiguration());
_connection.setEditingState(_value);
}
_connection.show();
}
void _closeInputConnectionIfNeeded() {
if (_hasInputConnection) {
_connection.close();
_connection = null;
}
}
#override
Widget build(BuildContext context) {
var chipsChildren = _chips
.map<Widget>(
(data) => widget.chipBuilder(context, this, data),
)
.toList();
final theme = Theme.of(context);
chipsChildren.add(
Container(
height: 32.0,
child: Row(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Text(
text,
style: theme.textTheme.subtitle1.copyWith(
height: 1.5,
),
),
_TextCaret(
resumed: _focusNode.hasFocus,
),
],
),
),
);
return Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
//mainAxisSize: MainAxisSize.min,
children: <Widget>[
GestureDetector(
behavior: HitTestBehavior.opaque,
onTap: requestKeyboard,
child: InputDecorator(
decoration: widget.decoration,
isFocused: _focusNode.hasFocus,
isEmpty: _value.text.length == 0,
child: Wrap(
children: chipsChildren,
spacing: 4.0,
runSpacing: 4.0,
),
),
),
Expanded(
child: ListView.builder(
itemCount: _suggestions?.length ?? 0,
itemBuilder: (BuildContext context, int index) {
return widget.suggestionBuilder(
context, this, _suggestions[index]);
},
),
),
],
);
}
#override
void updateEditingValue(TextEditingValue value) {
final oldCount = _countReplacements(_value);
final newCount = _countReplacements(value);
setState(() {
if (newCount < oldCount) {
_chips = Set.from(_chips.take(newCount));
}
_value = value;
});
_onSearchChanged(text);
}
int _countReplacements(TextEditingValue value) {
return value.text.codeUnits
.where((ch) => ch == kObjectReplacementChar)
.length;
}
#override
void performAction(TextInputAction action) {
_focusNode.unfocus();
}
void _updateTextInputState() {
final text =
String.fromCharCodes(_chips.map((_) => kObjectReplacementChar));
_value = TextEditingValue(
text: text,
selection: TextSelection.collapsed(offset: text.length),
composing: TextRange(start: 0, end: text.length),
);
_connection.setEditingState(_value);
}
void _onSearchChanged(String value) async {
final localId = ++_searchId;
final results = await widget.findSuggestions(value);
if (_searchId == localId && mounted) {
setState(() => _suggestions = results
.where((profile) => !_chips.contains(profile))
.toList(growable: false));
}
}
noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
}
class _TextCaret extends StatefulWidget {
const _TextCaret({
Key key,
this.duration = const Duration(milliseconds: 500),
this.resumed = false,
}) : super(key: key);
final Duration duration;
final bool resumed;
#override
_TextCursorState createState() => _TextCursorState();
}
class _TextCursorState extends State<_TextCaret>
with SingleTickerProviderStateMixin {
bool _displayed = false;
Timer _timer;
#override
void initState() {
super.initState();
_timer = Timer.periodic(widget.duration, _onTimer);
}
void _onTimer(Timer timer) {
setState(() => _displayed = !_displayed);
}
#override
void dispose() {
_timer.cancel();
super.dispose();
}
#override
Widget build(BuildContext context) {
final theme = Theme.of(context);
return FractionallySizedBox(
heightFactor: 0.7,
child: Opacity(
opacity: _displayed && widget.resumed ? 1.0 : 0.0,
child: Container(
width: 2.0,
color: theme.primaryColor,
),
),
);
}
}
Working output:
Aside from the samples above, you have the option to use flutter_chips_input plugin.
Flutter library for building input fields with InputChips as input
options.
Here is an example: