Android - MQTT and Mosquitto

I'm working in a project that trying to publish and subscribe to the MQTTHOST test.mosquitto.org:1833
But when I run my code, always occurrs "you app keeps stopping".

I used the same code from the youtube video, (Paho): https://www.youtube.com/watch?v=BAkGm02WBc0

My code:

MainActivity

package com.carlospacheco.mce_app_ifsp;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;
import org.eclipse.paho.android.service.MqttAndroidClient;
import org.eclipse.paho.client.mqttv3.IMqttActionListener;
import org.eclipse.paho.client.mqttv3.IMqttToken;
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttConnectOptions;
import org.eclipse.paho.client.mqttv3.MqttException;
public class MainActivity extends AppCompatActivity {
static String MQTTHOST  = "test.mosquitto.org:1883";
static String USERNAME  = "";
static String PASSWORD  = "";
String topicStr = "LED";
MqttAndroidClient client;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String clientId = MqttClient.generateClientId();
client = new MqttAndroidClient(this.getApplicationContext(), MQTTHOST, clientId);
MqttConnectOptions options = new MqttConnectOptions();
options.setUserName(USERNAME);
options.setPassword(PASSWORD.toCharArray());
try {
IMqttToken token = client.connect(options);
token.setActionCallback(new IMqttActionListener() {
@Override
public void onSuccess(IMqttToken asyncActionToken) {
Toast.makeText(MainActivity.this,"Conectado!", Toast.LENGTH_LONG).show();
}
@Override
public void onFailure(IMqttToken asyncActionToken, Throwable exception) {
Toast.makeText(MainActivity.this,"Conexão Falhou!", Toast.LENGTH_LONG).show();
}
});
} catch (MqttException e) {
e.printStackTrace();
}
}
public void pub(View v){
String topic = topicStr;
String message = "hello world from ifi gaming";
try {
client.publish(topic, message.getBytes(),0, false);
} catch (MqttException e) {
e.printStackTrace();
}
}
}

build.gradle

apply plugin: 'com.android.application'
android {
compileSdkVersion 29
buildToolsVersion "29.0.3"
defaultConfig {
applicationId "com.carlospacheco.mce_app_ifsp"
minSdkVersion 16
targetSdkVersion 29
versionCode 1
versionName "1.0"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
}
}
repositories {
maven {
url "https://repo.eclipse.org/content/repositories/paho-releases/"
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'androidx.appcompat:appcompat:1.2.0'
implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
implementation 'androidx.localbroadcastmanager:localbroadcastmanager:1.0.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'androidx.test.ext:junit:1.1.1'
androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
compile('org.eclipse.paho:org.eclipse.paho.android.service:1.0.2') {
exclude module: 'support-v4'
}
}

activity main

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Conectar"
android:onClick="pub"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
tools:layout_editor_absoluteY="45dp" />
</androidx.constraintlayout.widget.ConstraintLayout>

As I said in the comments, without the full exception stack trace this question is impossible to answer properly but I'll take a guess

The value of MQTTHOST is supposed to be a full URI pointing at the MQTT broker. At the moment you have test.mosquitto.org:1883 which is not a full URI.

A full URI needs to include a protocol before the host section.

In this case you need to add either tcp:// or mqtt:// before the host and port components.

static String MQTTHOST = "tcp://test.mosquitto.org:1883";