Flutter: Subscribe to channel

Subscribe to realtime changes in your database.

• Realtime is disabled by default for new tables. You can turn it on by managing replication.
• If you want to receive the "previous" data for updates and deletes, you will need to set REPLICA IDENTITY to FULL, like this: ALTER TABLE your_table REPLICA IDENTITY FULL;

Examples

Listen to database changes

supabase .channel('public:countries') .onPostgresChanges( event: PostgresChangeEvent.all, schema: 'public', table: 'countries', callback: (payload) { print('Change received: ${payload.toString()}'); }) .subscribe(); 

Listen to inserts

supabase .channel('public:countries') .onPostgresChanges( event: PostgresChangeEvent.insert, schema: 'public', table: 'countries', callback: (payload) { print('Change received: ${payload.toString()}'); }) .subscribe(); 

Listen to updates

supabase .channel('public:countries') .onPostgresChanges( event: PostgresChangeEvent.update, schema: 'public', table: 'countries', callback: (payload) { print('Change received: ${payload.toString()}'); }) .subscribe(); 

Listen to deletes

supabase .channel('public:countries') .onPostgresChanges( event: PostgresChangeEvent.delete, schema: 'public', table: 'countries', callback: (payload) { print('Change received: ${payload.toString()}'); }) .subscribe(); 

Listen to multiple events

supabase .channel('public:countries') .onPostgresChanges( event: PostgresChangeEvent.insert, schema: 'public', table: 'countries', callback: (payload) { print('Insert event received: ${payload.toString()}'); }) .onPostgresChanges( event: PostgresChangeEvent.delete, schema: 'public', table: 'countries', callback: (payload) { print('Delete event received: ${payload.toString()}'); }) .subscribe(); 

Listen to row level changes

supabase .channel('public:countries:id=eq.200') .onPostgresChanges( event: PostgresChangeEvent.delete, schema: 'public', table: 'countries', filter: PostgresChangeFilter( type: PostgresChangeFilterType.eq, column: 'id', value: 200, ), callback: (payload) { print('Change received: ${payload.toString()}'); }) .subscribe(); 

Listen to broadcast messages

supabase .channel('room1') .onBroadcast( event: 'cursor-pos', callback: (payload) { print('Cursor position received!: $payload'); }) .subscribe(); 

Listen to presence events

final channel = supabase.channel('room1'); channel.onPresenceSync((payload) { print('Synced presence state: ${channel.presenceState()}'); }).onPresenceJoin((payload) { print('Newly joined presences $payload'); }).onPresenceLeave((payload) { print('Newly left presences: $payload'); }).subscribe((status, error) async { if (status == RealtimeSubscribeStatus.subscribed) { await channel.track({'online_at': DateTime.now().toIso8601String()}); } });