I tried to connect my local mosquitto mqtt broker to Android Studio to be able to receive data which is sent from an esp32 via mqtt, but I always get an system error.
I have mosquitto running locally and that works fine, but when i try to connect to the broker from Android Studio i always get a system error.
This is my code:
package com.example.pulsapp;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;import android.widget.Toast;import androidx.appcompat.app.AppCompatActivity;public class MainActivity extends AppCompatActivity {private static final String BROKER_URL = "tcp://192.168.178.48:1883";private static final String CLIENT_ID = "xxx";private static final String topic = "test";private MqttHandler mqttHandler;private Button btn;@Overrideprotected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mqttHandler = new MqttHandler(); mqttHandler.connect(BROKER_URL,CLIENT_ID); init();}private void init() { btn = findViewById(R.id.btn_sub); //client = new MqttAndroidClient(this.getApplicationContext(), MQTT_BROKER_URL, clientID); btn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { subscribeToTopic("test"); } });}@Overrideprotected void onDestroy() { mqttHandler.disconnect(); super.onDestroy();}private void publishMessage(String topic, String message){ Toast.makeText(this, "Publishing message: " + message, Toast.LENGTH_SHORT).show(); mqttHandler.publish(topic,message);}private void subscribeToTopic(String topic){ Toast.makeText(this, "Subscribing to topic "+ topic, Toast.LENGTH_SHORT).show(); mqttHandler.subscribe(topic);}}
And this is the error I get:
2024-06-15 12:38:56.015 11861-11861 System.err com.example.pulsapp W Client is not connected (32104)2024-06-15 12:38:56.015 11861-11861 System.err com.example.pulsapp W at org.eclipse.paho.client.mqttv3.internal.ExceptionHelper.createMqttException(ExceptionHelper.java:31)2024-06-15 12:38:56.016 11861-11861 System.err com.example.pulsapp W at org.eclipse.paho.client.mqttv3.internal.ClientComms.sendNoWait(ClientComms.java:205)2024-06-15 12:38:56.017 11861-11861 System.err com.example.pulsapp W at org.eclipse.paho.client.mqttv3.MqttAsyncClient.subscribeBase(MqttAsyncClient.java:1088)2024-06-15 12:38:56.018 11861-11861 System.err com.example.pulsapp W at org.eclipse.paho.client.mqttv3.MqttAsyncClient.subscribe(MqttAsyncClient.java:1152)2024-06-15 12:38:56.019 11861-11861 System.err com.example.pulsapp W at org.eclipse.paho.client.mqttv3.MqttClient.subscribe(MqttClient.java:459)2024-06-15 12:38:56.019 11861-11861 System.err com.example.pulsapp W at org.eclipse.paho.client.mqttv3.MqttClient.subscribe(MqttClient.java:429)2024-06-15 12:38:56.019 11861-11861 System.err com.example.pulsapp W at org.eclipse.paho.client.mqttv3.MqttClient.subscribe(MqttClient.java:404)2024-06-15 12:38:56.019 11861-11861 System.err com.example.pulsapp W at com.example.pulsapp.MqttHandler.subscribe(MqttHandler.java:50)2024-06-15 12:38:56.020 11861-11861 System.err com.example.pulsapp W at com.example.pulsapp.MainActivity.subscribeToTopic(MainActivity.java:54)2024-06-15 12:38:56.020 11861-11861 System.err com.example.pulsapp W at com.example.pulsapp.MainActivity.access$000(MainActivity.java:13)2024-06-15 12:38:56.020 11861-11861 System.err com.example.pulsapp W at com.example.pulsapp.MainActivity$1.onClick(MainActivity.java:37)2024-06-15 12:38:56.021 11861-11861 System.err com.example.pulsapp W at android.view.View.performClick(View.java:7659)2024-06-15 12:38:56.021 11861-11861 System.err com.example.pulsapp W at com.google.android.material.button.MaterialButton.performClick(MaterialButton.java:1218)2024-06-15 12:38:56.021 11861-11861 System.err com.example.pulsapp W at android.view.View.performClickInternal(View.java:7636)2024-06-15 12:38:56.022 11861-11861 System.err com.example.pulsapp W at android.view.View.-$$Nest$mperformClickInternal(Unknown Source:0)2024-06-15 12:38:56.023 11861-11861 System.err com.example.pulsapp W at android.view.View$PerformClick.run(View.java:30156)2024-06-15 12:38:56.023 11861-11861 System.err com.example.pulsapp W at android.os.Handler.handleCallback(Handler.java:958)2024-06-15 12:38:56.023 11861-11861 System.err com.example.pulsapp W at android.os.Handler.dispatchMessage(Handler.java:99)2024-06-15 12:38:56.024 11861-11861 System.err com.example.pulsapp W at android.os.Looper.loopOnce(Looper.java:205)2024-06-15 12:38:56.024 11861-11861 System.err com.example.pulsapp W at android.os.Looper.loop(Looper.java:294)2024-06-15 12:38:56.025 11861-11861 System.err com.example.pulsapp W at android.app.ActivityThread.main(ActivityThread.java:8177)2024-06-15 12:38:56.025 11861-11861 System.err com.example.pulsapp W at java.lang.reflect.Method.invoke(Native Method)2024-06-15 12:38:56.026 11861-11861 System.err com.example.pulsapp W at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:552)2024-06-15 12:38:56.027 11861-11861 System.err com.example.pulsapp W at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:971)