> For the complete documentation index, see [llms.txt](https://playnetwork.gitbook.io/play-sdk-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://playnetwork.gitbook.io/play-sdk-documentation/sdk-integration-guides/notifications/unity.md).

# Unity

Unity integration

The **MessagingModule** class contains various methods that are used for subscribing and unsubscribing to topics, sending messages to a particular user (for admin users only), and receiving messages from the messaging service.

#### Currently supported topics:

1. **RGN.Modules.Inventory.InventoryModule.ITEM\_ADDED\_EVENT\_TOPIC** - this event is triggered when a new virtual item is added to the user's inventory by using the `RGN.Modules.Inventory.InventoryModule.AddToInventoryAsync` method.
2. **RGN.Modules.Inventory.InventoryModule.ITEM\_REMOVED\_EVENT\_TOPIC** - this event is triggered when an inventory item is removed by using the `RGN.Modules.Inventory.InventoryModule.RemoveByInventoryItemIdAsync` method.

### Subscribe and Unsubscribe

The Subscribe method is used to subscribe the message receiver to a particular topic:

`void Subscribe(string topic, IMessageReceiver messageReceiver)`

`IMessageReceiver`  interface is intended to be implemented by classes that want to receive and handle messages. The `IMessageReceiver` interface defines a single method named `OnMessageReceived`, which takes two parameters - a `string` named `topic` and an object of the type `Message`.

The `topic` parameter is used to identify the specific topic or channel that the message was sent on and the `message` parameter contains the actual message data.

The Unsubscribe method is used to unsubscribe the message receiver from a particular topic. 

Here is a code example:

```csharp
using UnityEngine;
using RGN.Modules.Messaging;

public class MessagingExamples : MonoBehaviour, IMessageReceiver
{
    private void Start()
    {
        // TODO: use module constants for topic parameter, for example:
        // RGN.Modules.Inventory.InventoryModule.ITEM_ADDED_EVENT_TOPIC
        MessagingModule.I.Subscribe("it_is_better_to_use_module_constants", this);
    }

    private void OnDestroy()
    {
        MessagingModule.I.Unsubscribe("it_is_better_to_use_module_constants", this);
    }

    public void OnMessageReceived(string topic, Message message)
    {
        Debug.Log($"New message received for topic : {topic}, message : {message}");
    }
}
```

The sample above shows an implementation of the `IMessageReceiver` interface in a class called `SomeNotificationReceiver`. This class inherits from `MonoBehaviour`, which is a Unity class that allows for the creation of scripts that can be attached to game objects in a Unity scene.

The `SomeNotificationReceiver` class subscribes to a specific message topic by calling the `MessagingModule.I.Subscribe` method and passing in the topic string and an instance of itself as the message receiver. It also unsubscribes from the same topic in its `OnDestroy` method by calling the `MessagingModule.I.Unsubscribe` method.

The `OnMessageReceived` method simply logs a message to the Unity console with the topic and message received. You can implement your own message handling code.