stream_chat_flutter_core 1.5.2 stream_chat_flutter_core: ^1.5.2 copied to clipboard
Stream Chat official Flutter SDK Core. Build your own chat experience using Dart and Flutter.
import 'package:flutter/material.dart';
import 'package:stream_chat_flutter_core/stream_chat_flutter_core.dart';
Future<void> main() async {
/// Create a new instance of [StreamChatClient] passing the apikey obtained from your
/// project dashboard.
final client = StreamChatClient('b67pax5b2wdq');
/// Set the current user. In a production scenario, this should be done using
/// a backend to generate a user token using our server SDK.
/// Please see the following for more information:
/// https://getstream.io/chat/docs/ios_user_setup_and_tokens/
await client.connectUser(
User(
id: 'cool-shadow-7',
extraData: {
'image':
'https://getstream.io/random_png/?id=cool-shadow-7&name=Cool+shadow',
},
),
'eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJ1c2VyX2lkIjoiY29vbC1zaGFkb3ctNyJ9.gkOlCRb1qgy4joHPaxFwPOdXcGvSPvp6QY0S4mpRkVo',
);
runApp(
StreamExample(
client: client,
),
);
}
/// Example application using Stream Chat core widgets.
/// Stream Chat Core is a set of Flutter wrappers which provide basic functionality
/// for building Flutter applications using Stream.
/// If you'd prefer using pre-made UI widgets for your app, please see our other
/// package, `stream_chat_flutter`.
class StreamExample extends StatelessWidget {
/// Minimal example using Stream's core Flutter package.
/// If you'd prefer using pre-made UI widgets for your app, please see our other
/// package, `stream_chat_flutter`.
const StreamExample({
Key key,
@required this.client,
}) : super(key: key);
/// Instance of Stream Client.
/// Stream's [StreamChatClient] can be used to connect to our servers and set the default
/// user for the application. Performing these actions trigger a websocket connection
/// allowing for real-time updates.
final StreamChatClient client;
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Stream Chat Core Example',
home: HomeScreen(),
builder: (context, child) => StreamChatCore(
client: client,
child: child,
),
);
}
}
/// Basic layout displaying a list of [Channel]s the user is a part of.
/// This is implemented using [ChannelListCore].
///
/// [ChannelListCore] is a `builder` with callbacks for constructing UIs based
/// on different scenarios.
class HomeScreen extends StatelessWidget {
final channelListController = ChannelListController();
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Channels'),
),
body: ChannelsBloc(
child: ChannelListCore(
channelListController: channelListController,
filter: {
'type': 'messaging',
'members': {
r'$in': [
StreamChatCore.of(context).user.id,
]
}
},
emptyBuilder: (BuildContext context) {
return Center(
child: Text('Looks like you are not in any channels'),
);
},
loadingBuilder: (BuildContext context) {
return Center(
child: SizedBox(
height: 100.0,
width: 100.0,
child: CircularProgressIndicator(),
),
);
},
errorBuilder: (BuildContext context, dynamic error) {
return Center(
child: Text(
'Oh no, something went wrong. Please check your config.'),
);
},
listBuilder: (
BuildContext context,
List<Channel> channels,
) =>
LazyLoadScrollView(
onEndOfPage: () async {
channelListController.paginateData();
},
child: ListView.builder(
itemCount: channels.length,
itemBuilder: (BuildContext context, int index) {
final _item = channels[index];
return ListTile(
title: Text(_item.name),
subtitle: StreamBuilder<Message>(
stream: _item.state.lastMessageStream,
initialData: _item.state.lastMessage,
builder: (context, snapshot) {
if (snapshot.hasData) {
return Text(snapshot.data.text);
}
return SizedBox();
},
),
onTap: () {
/// Display a list of messages when the user taps on an item.
/// We can use [StreamChannel] to wrap our [MessageScreen] screen
/// with the selected channel.
///
/// This allows us to use a built-in inherited widget for accessing
/// our `channel` later on.
Navigator.of(context).push(
MaterialPageRoute(
builder: (context) => StreamChannel(
channel: _item,
child: MessageScreen(),
),
),
);
},
);
},
),
),
),
),
);
}
}
/// A list of messages sent in the current channel.
/// When a user taps on a channel in [HomeScreen], a navigator push [MessageScreen]
/// to display the list of messages in the selected channel.
///
/// This is implemented using [MessageListCore], a convenience builder with
/// callbacks for building UIs based on different api results.
class MessageScreen extends StatefulWidget {
@override
_MessageScreenState createState() => _MessageScreenState();
}
class _MessageScreenState extends State<MessageScreen> {
TextEditingController _controller;
ScrollController _scrollController;
final messageListController = MessageListController();
@override
void initState() {
super.initState();
_controller = TextEditingController();
_scrollController = ScrollController();
}
@override
void dispose() {
_controller.dispose();
_scrollController.dispose();
super.dispose();
}
void _updateList() {
_scrollController.animateTo(
0,
duration: const Duration(milliseconds: 200),
curve: Curves.easeOut,
);
}
@override
Widget build(BuildContext context) {
/// To access the current channel, we can use the `.of()` method on [StreamChannel]
/// to fetch the closest instance.
final channel = StreamChannel.of(context).channel;
return Scaffold(
appBar: AppBar(
title: StreamBuilder<List<User>>(
initialData: channel.state.typingEvents,
stream: channel.state.typingEventsStream,
builder: (context, snapshot) {
if (snapshot.hasData && snapshot.data.isNotEmpty) {
return Text('${snapshot.data.first.name} is typing...');
}
return SizedBox();
},
),
),
body: SafeArea(
child: Column(
children: [
Expanded(
child: LazyLoadScrollView(
onEndOfPage: () async {
messageListController.paginateData();
},
child: MessageListCore(
emptyBuilder: (BuildContext context) {
return Center(
child: Text('Nothing here yet'),
);
},
loadingBuilder: (BuildContext context) {
return Center(
child: SizedBox(
height: 100.0,
width: 100.0,
child: CircularProgressIndicator(),
),
);
},
messageListBuilder: (
BuildContext context,
List<Message> messages,
) {
return ListView.builder(
controller: _scrollController,
itemCount: messages.length,
reverse: true,
itemBuilder: (BuildContext context, int index) {
final item = messages[index];
final client = StreamChatCore.of(context).client;
if (item.user.id == client.uid) {
return Align(
alignment: Alignment.centerRight,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Text(item.text),
),
);
} else {
return Align(
alignment: Alignment.centerLeft,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Text(item.text),
),
);
}
},
);
},
errorWidgetBuilder: (BuildContext context, error) {
print(error?.toString());
return Center(
child: SizedBox(
height: 100.0,
width: 100.0,
child:
Text('Oh no, an error occured. Please see logs.'),
),
);
},
),
),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Row(
children: [
Expanded(
child: TextField(
controller: _controller,
decoration: const InputDecoration(
hintText: 'Enter your message',
),
),
),
Material(
type: MaterialType.circle,
color: Colors.blue,
clipBehavior: Clip.hardEdge,
child: InkWell(
onTap: () async {
if (_controller.value.text.isNotEmpty) {
await channel.sendMessage(
Message(text: _controller.value.text),
);
_controller.clear();
_updateList();
}
},
child: const Padding(
padding: EdgeInsets.all(8.0),
child: Center(
child: Icon(
Icons.send,
color: Colors.white,
),
),
),
),
)
],
),
)
],
),
),
);
}
}
/// Extensions can be used to add functionality to the SDK. In the examples
/// below, we add two simple extensions to the [StreamChatClient] and [Channel].
extension on StreamChatClient {
/// Fetches the current user id.
String get uid => state.user.id;
}
extension on Channel {
/// Fetches the name of the channel by accessing [extraData] or [cid].
String get name {
final _channelName = extraData['name'];
if (_channelName != null) {
return _channelName;
} else {
return cid;
}
}
}