channel method
Returns a ReadonlySignal reflecting the latest message payload on channelName.
Starts with a value of null. Each incoming broadcast event on channelName
updates the signal. Repeated calls with the same channelName return the existing cached signal.
final notifications = binding.channel('notifications');
Implementation
ReadonlySignal<Map<String, dynamic>?> channel(String channelName) {
if (_channelSignals.containsKey(channelName)) {
return _channelSignals[channelName]!.readonly();
}
final sig = signal<Map<String, dynamic>?>(null);
_channelSignals[channelName] = sig;
_subs.add(client.subscribe(channelName).listen((msg) => sig.value = msg));
return sig.readonly();
}