ChannelListHeader

A Header Widget For A List Of Channels

Find the pub.dev documentation here

Background

A common pattern for most messaging apps is to show a list of Channels (chats) on the first screen and navigate to an individual one on being clicked. On this first page where the list of channels are displayed, it is usual to have functionality such as adding a new chat, display the user logged in, etc.

To encapsulate all of this functionality into one widget, the Flutter SDK contains a ChannelListHeader widget which provides these out of the box.

Basic Example

This is a basic example of a page which has a ChannelListView and a ChannelListHeader to recreate a common Channels Page.

class DemoPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: ChannelListHeader(),
      body: ChannelsBloc(
         child: ChannelListView(
           filter: Filter.in_('members', [StreamChat.of(context).user.id]),
           sort: [SortOption('last_message_at')],
           pagination: PaginationParams(
             limit: 20,
           ),
           channelWidget: ChannelPage(),
         ),
      ),
    );
  }
}

Customizing Parts Of The Header

The header works like a ListTile widget.

Use the titleBuilder, subtitle, leading, or actions parameters to substitute the widgets for your own.

//...
ChannelListHeader(
    subtitle: Text('My Custom Subtitle'),
),

The titleBuilder parameter helps you build different titles depending on the connection state:

//...
ChannelListHeader(
    titleBuilder: (context, status, client) {
        switch(status) {
            /// Return your title widget
        }
    },
),

Showing Connection State

The ChannelListHeader can also display connection state below the tile which shows the user if they are connected or offline, etc. on connection events.

To enable this, use the showConnectionStateTile property.

//...
ChannelListHeader(
    showConnectionStateTile: true,
),