Add dependencies to your build.gradle

dependencies {
    compile 'com.robocreative.android:robo-common:1.0'
    compile 'com.robocreative.android:robo-messaging:1.0'
}

Every message has to be implementation of interface com.robo.messaging.Message. There is also an abstract class named com.robo.messaging.AbstractMessage providing the base for implementing Message. Below is an example:

package com.example.myapplication;

import com.robo.messaging.AbstractMessage;

public class MyMessage extends AbstractMessage<String> {

    protected MyMessage(String content) {
        super(content);
    }
}

Create a subscriber that receives messages of MyMessage

package com.example.myapplication;

import android.util.Log;

import com.robo.messaging.MessageBus;
import com.robo.messaging.Subscriber;

public class MySubscriber {

    private MessageBus mMessageBus;

    public MySubscriber(MessageBus messageBus) {
        mMessageBus = messageBus;
    }

    public void doSubscribe() {
        mMessageBus.subscribe(new Subscriber<MyMessage>() {
            @Override
            public void receive(MyMessage message) {
                Log.d("MessageBus", "Received message: " + message.getContent());
            }
        });
    }
}

Create a publisher that publishes a message of MyMessage

package com.example.myapplication;

import com.robo.messaging.MessageBus;

public class MyPublisher {

    private MessageBus mMessageBus;

    public MyPublisher(MessageBus messageBus) {
        mMessageBus = messageBus;
    }

    public void doPublish(String content) {
        mMessageBus.publish(new MyMessage(content));
    }
}

Place following statements inside your application to launch the first test:

MessageBus messageBus = new MessageBusImp();

MySubscriber subscriber = new MySubscriber(messageBus);
subscriber.doSubscribe();

MyPublisher publisher = new MyPublisher(messageBus);
publisher.doPublish("Hello world!");

That's how to quickly use Message Bus in minutes. You can find more interesting features in upcoming pages.

Further Reading