Mqtt never return callback connection lost when broker server disconnect the network(wifi).

[mintheinwin]

I integrated an MQTT broker into my app, establishing a connection between the Android device and the Mosquitto broker on a computer server. However, in my scenario, when I disconnect the Wi-Fi on the server, the broker connection doesn't trigger the callback method to indicate connection loss on Android.

// for Mqtt dependencies implementation 'androidx.legacy:legacy-support-v4:1.0.0' implementation 'com.github.hannesa2:paho.mqtt.android:4.2'

protected void mqttBrokerStartConnect(String deviceId) {

    IMqttToken token;
    String brokerIP = AppSharePreference.getMQTTBrokerIP(getBaseContext());
    String uri = "tcp://" + brokerIP;
    //String clientId = MqttClient.generateClientId();
    String clientId = "MyClientId";

    mqttClient = new MqttAndroidClient(getApplicationContext(), uri, clientId, Ack.AUTO_ACK);
    mqttClient.setTraceEnabled(true);
    // Work in the UI thread
    MqttConnectOptions connectOptions = new MqttConnectOptions();
    connectOptions.setUserName("username");
    connectOptions.setPassword("password".toCharArray());
    connectOptions.setCleanSession(false);
    String message = payLoadConnection(deviceId);
    connectOptions.setWill(CommonConstants.willDisconnectTopic, message.getBytes(), 0, false);
    connectOptions.setAutomaticReconnect(true);
    connectOptions.setConnectionTimeout(10); // Set connection timeout to 10 seconds
    connectOptions.setKeepAliveInterval(60);

    token = mqttClient.connect(connectOptions);
    token.setActionCallback(this);
    mqttClient.setCallback(this);
    mqttClient.setTraceCallback(this);

}

@Override
public void connectionLost(Throwable cause) {
    EventBus.getDefault().post(new ResultEvent.MqttConnectionStatusEvent(getBaseContext(), false));
   // mqttClient.connect();
}