sendMessage method
Implementation
@override
void sendMessage(String text) {
var stanza =
MessageStanza(AbstractStanza.getRandomId(), MessageStanzaType.CHAT);
stanza.toJid = _jid;
stanza.fromJid = _connection.fullJid;
stanza.body = text;
var message = Message.fromStanza(stanza);
messages!.add(message);
_newMessageController.add(message);
_connection.writeStanza(stanza);
}