---
title: "SecondScreen"
slug: "170-core-secondscreen"
updated: 2025-12-09T17:12:47Z
published: 2025-12-09T18:02:06Z
canonical: "docs.developer.comcast.com/170-core-secondscreen"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.developer.comcast.com/llms.txt
> Use this file to discover all available pages before exploring further.

# SecondScreen

**SecondScreen Module 1.7.0 | Core SDK**

## Usage

To use the SecondScreen module, you can import it into your project from the Firebolt SDK:

```
import { SecondScreen } from '@firebolt-js/sdk'
```

## Overview

Methods for communicating with second screen devices

## Methods

### device

Get the broadcasted id for the device

```
function device(type: string): Promise<string>
```

Parameters:

| Param | Type | Required | Description |
| --- | --- | --- | --- |
| `type` | `string` | false | The type of second screen protocol, e.g. "dial" |

Promise resolution:

Capabilities:

| Role | Capability |
| --- | --- |
| uses | xrn:firebolt:capability:protocol:dial |

#### Examples

Default Example

JavaScript:

```
import { SecondScreen } from '@firebolt-js/sdk'

let deviceId = await SecondScreen.device()
console.log(deviceId)
```

Value of `deviceId`:

```
'device-id'
```

**JSON-RPC:**

Request:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SecondScreen.device",
  "params": {}
}
```

Response:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "device-id"
}
```

---

### friendlyName

Get the broadcasted friendly name for the device

To get the value of `friendlyName` call the method like this:

```
function friendlyName(): Promise<string>
```

Promise resolution:

Capabilities:

| Role | Capability |
| --- | --- |
| uses | xrn:firebolt:capability:protocol:dial |

#### Examples

Default Example

JavaScript:

```
import { SecondScreen } from '@firebolt-js/sdk'

let friendlyName = await SecondScreen.friendlyName()
console.log(friendlyName)
```

Value of `friendlyName`:

```
'Living Room'
```

**JSON-RPC:**

Request:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SecondScreen.friendlyName",
  "params": {}
}
```

Response:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "Living Room"
}
```

---

To subscribe to notifications when the value changes, call the method like this:

```
function friendlyName(callback: (value) => string): Promise<number>
```

Promise resolution:

```
number
```

#### Examples

Default Example

JavaScript:

```
import { SecondScreen } from '@firebolt-js/sdk'

let listenerId = await friendlyName((value) => {
  console.log(value)
})
console.log(listenerId)
```

Value of `friendlyName`:

```
'Living Room'
```

**JSON-RPC:**

Request:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SecondScreen.onFriendlyNameChanged",
  "params": {
    "listen": true
  }
}
```

Response:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "Living Room"
}
```

---

### listen

To listen to a specific event pass the event name as the first parameter:

```
listen(event: string, callback: (data: any) => void): Promise<number>
```

Parameters:

| Param | Type | Required | Summary |
| --- | --- | --- | --- |
| `event` | `string` | Yes | The event to listen for, see [Events](/docs/170-core-secondscreen#events). |
| *callback* | `function` | Yes | A function that will be invoked when the event occurs. |

Promise resolution:

| Type | Description |
| --- | --- |
| `number` | Listener ID to clear the callback method and stop receiving the event, e.g. `SecondScreen.clear(id)` |

Callback parameters:

| Param | Type | Required | Summary |
| --- | --- | --- | --- |
| `data` | `any` | Yes | The event data, which depends on which event is firing, see [Events](/docs/170-core-secondscreen#events). |

To listen to all events from this module pass only a callback, without specifying an event name:

```
listen(callback: (event: string, data: any) => void): Promise<number>
```

Parameters:

| Param | Type | Required | Summary |
| --- | --- | --- | --- |
| *callback* | `function` | Yes | A function that will be invoked when the event occurs. The event data depends on which event is firing, see [Events](/docs/170-core-secondscreen#events). |

Callback parameters:

| Param | Type | Required | Summary |
| --- | --- | --- | --- |
| `event` | `string` | Yes | The event that has occured listen for, see [Events](/docs/170-core-secondscreen#events). |
| `data` | `any` | Yes | The event data, which depends on which event is firing, see [Events](/docs/170-core-secondscreen#events). |

Promise resolution:

| Type | Description |
| --- | --- |
| `number` | Listener ID to clear the callback method and stop receiving the event, e.g. `SecondScreen.clear(id)` |

See [Listening for events](/docs/listening-for-events/) for more information and examples.

### once

To listen to a single instance of a specific event pass the event name as the first parameter:

```
once(event: string, callback: (data: any) => void): Promise<number>
```

The `once` method will only pass the next instance of this event, and then dicard the listener you provided.

Parameters:

| Param | Type | Required | Summary |
| --- | --- | --- | --- |
| `event` | `string` | Yes | The event to listen for, see [Events](/docs/170-core-secondscreen#events). |
| *callback* | `function` | Yes | A function that will be invoked when the event occurs. |

Promise resolution:

| Type | Description |
| --- | --- |
| `number` | Listener ID to clear the callback method and stop receiving the event, e.g. `SecondScreen.clear(id)` |

Callback parameters:

| Param | Type | Required | Summary |
| --- | --- | --- | --- |
| `data` | `any` | Yes | The event data, which depends on which event is firing, see [Events](/docs/170-core-secondscreen#events). |

To listen to the next instance only of any events from this module pass only a callback, without specifying an event name:

```
once(callback: (event: string, data: any) => void): Promise<number>
```

Parameters:

| Param | Type | Required | Summary |
| --- | --- | --- | --- |
| *callback* | `function` | Yes | A function that will be invoked when the event occurs. The event data depends on which event is firing, see [Events](/docs/170-core-secondscreen#events). |

Callback parameters:

| Param | Type | Required | Summary |
| --- | --- | --- | --- |
| `event` | `string` | Yes | The event that has occured listen for, see [Events](/docs/170-core-secondscreen#events). |
| `data` | `any` | Yes | The event data, which depends on which event is firing, see [Events](/docs/170-core-secondscreen#events). |

Promise resolution:

| Type | Description |
| --- | --- |
| `number` | Listener ID to clear the callback method and stop receiving the event, e.g. `SecondScreen.clear(id)` |

See [Listening for events](/docs/listening-for-events/) for more information and examples.

### protocols

Get the supported second screen discovery protocols

```
function protocols(): Promise<BooleanMap>
```

Promise resolution:

[BooleanMap](/docs/170-core-Types-schemas#BooleanMap)

Capabilities:

| Role | Capability |
| --- | --- |
| uses | xrn:firebolt:capability:secondscreen:protocol |

#### Examples

Default Example

JavaScript:

```
import { SecondScreen } from '@firebolt-js/sdk'

let protocols = await SecondScreen.protocols()
console.log(protocols)
```

Value of `protocols`:

```
{
	"dial1.7": true
}
```

**JSON-RPC:**

Request:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SecondScreen.protocols",
  "params": {}
}
```

Response:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "dial1.7": true
  }
}
```

---

## Events

### closeRequest

```
function listen('closeRequest', () => void): Promise<number>
```

See also: [listen()](/docs/170-core-secondscreen#listen), [once()](/docs/170-core-secondscreen#listen), [clear()](/docs/170-core-secondscreen#listen).

Event value:

[SecondScreenEvent](/docs/170-core-SecondScreen-schemas#SecondScreenEvent)

Capabilities:

| Role | Capability |
| --- | --- |
| uses | xrn:firebolt:capability:protocol:dial |

#### Examples

Default Example

JavaScript:

```
import { SecondScreen } from '@firebolt-js/sdk'

SecondScreen.listen('closeRequest', (closeRequestEvent) => {
  console.log(closeRequestEvent)
})
```

Value of `closeRequestEvent`:

```
{
	"type": "dial",
	"version": "1.7"
}
```

**JSON-RPC:**

Request:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SecondScreen.onCloseRequest",
  "params": {
    "listen": true
  }
}
```

Response:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "type": "dial",
    "version": "1.7"
  }
}
```

---

### friendlyNameChanged

See: [friendlyName](/docs/170-core-secondscreen#friendlyname)

### launchRequest

```
function listen('launchRequest', () => void): Promise<number>
```

See also: [listen()](/docs/170-core-secondscreen#listen), [once()](/docs/170-core-secondscreen#listen), [clear()](/docs/170-core-secondscreen#listen).

Event value:

[SecondScreenEvent](/docs/170-core-SecondScreen-schemas#SecondScreenEvent)

Capabilities:

| Role | Capability |
| --- | --- |
| uses | xrn:firebolt:capability:protocol:dial |

#### Examples

Default Example

JavaScript:

```
import { SecondScreen } from '@firebolt-js/sdk'

SecondScreen.listen('launchRequest', (launchRequestEvent) => {
  console.log(launchRequestEvent)
})
```

Value of `launchRequestEvent`:

```
{
	"type": "dial",
	"version": "1.7",
	"data": "{\"code\":\"AQDPQZiQcb3KQ7gY7yy5tHTMbbkGHR9Zjp-KL53H3eKBZIeAt7O9UKYPu6B21l2UZVmIqkFXDXBmXvK4g2e3EgZtjMNmKPsTltgnRl95DImtOXjSpWtTjSaOkW4w1kZKUTwLKdwVWTzBVH8ERHorvLU6vCGOVHxXt65LNwdl5HKRweShVC1V9QsyvRnQS61ov0UclmrH_xZML2Bt-Q-rZFjey5MjwupIb4x4f53XUJMhjHpDHoIUKrjpdPDQvK2a\",\"friendlyName\":\"Operator_TX061AEI\",\"UDN\":\"608fef11-2800-482a-962b-23a6690c93c1\"}"
}
```

**JSON-RPC:**

Request:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SecondScreen.onLaunchRequest",
  "params": {
    "listen": true
  }
}
```

Response:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "type": "dial",
    "version": "1.7",
    "data": "{\"code\":\"AQDPQZiQcb3KQ7gY7yy5tHTMbbkGHR9Zjp-KL53H3eKBZIeAt7O9UKYPu6B21l2UZVmIqkFXDXBmXvK4g2e3EgZtjMNmKPsTltgnRl95DImtOXjSpWtTjSaOkW4w1kZKUTwLKdwVWTzBVH8ERHorvLU6vCGOVHxXt65LNwdl5HKRweShVC1V9QsyvRnQS61ov0UclmrH_xZML2Bt-Q-rZFjey5MjwupIb4x4f53XUJMhjHpDHoIUKrjpdPDQvK2a\",\"friendlyName\":\"Operator_TX061AEI\",\"UDN\":\"608fef11-2800-482a-962b-23a6690c93c1\"}"
  }
}
```

---

## Private Events

**View**

  

### closeRequest

```
function listen('closeRequest', () => void): Promise<number>
```

See also: [listen()](/docs/170-core-secondscreen#listen), [once()](/docs/170-core-secondscreen#listen), [clear()](/docs/170-core-secondscreen#listen).

Event value:

[SecondScreenEvent](/docs/170-core-SecondScreen-schemas#SecondScreenEvent)

Capabilities:

| Role | Capability |
| --- | --- |
| uses | xrn:firebolt:capability:protocol:dial |

#### Examples

Default Example

JavaScript:

```
import { SecondScreen } from '@firebolt-js/sdk'

SecondScreen.listen('closeRequest', (closeRequestEvent) => {
  console.log(closeRequestEvent)
})
```

Value of `closeRequestEvent`:

```
{
	"type": "dial",
	"version": "1.7"
}
```

**JSON-RPC:**

Request:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SecondScreen.onCloseRequest",
  "params": {
    "listen": true
  }
}
```

Response:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "type": "dial",
    "version": "1.7"
  }
}
```

---

### friendlyNameChanged

See: [friendlyName](/docs/170-core-secondscreen#friendlyname)

### launchRequest

```
function listen('launchRequest', () => void): Promise<number>
```

See also: [listen()](/docs/170-core-secondscreen#listen), [once()](/docs/170-core-secondscreen#listen), [clear()](/docs/170-core-secondscreen#listen).

Event value:

[SecondScreenEvent](/docs/170-core-SecondScreen-schemas#SecondScreenEvent)

Capabilities:

| Role | Capability |
| --- | --- |
| uses | xrn:firebolt:capability:protocol:dial |

#### Examples

Default Example

JavaScript:

```
import { SecondScreen } from '@firebolt-js/sdk'

SecondScreen.listen('launchRequest', (launchRequestEvent) => {
  console.log(launchRequestEvent)
})
```

Value of `launchRequestEvent`:

```
{
	"type": "dial",
	"version": "1.7",
	"data": "{\"code\":\"AQDPQZiQcb3KQ7gY7yy5tHTMbbkGHR9Zjp-KL53H3eKBZIeAt7O9UKYPu6B21l2UZVmIqkFXDXBmXvK4g2e3EgZtjMNmKPsTltgnRl95DImtOXjSpWtTjSaOkW4w1kZKUTwLKdwVWTzBVH8ERHorvLU6vCGOVHxXt65LNwdl5HKRweShVC1V9QsyvRnQS61ov0UclmrH_xZML2Bt-Q-rZFjey5MjwupIb4x4f53XUJMhjHpDHoIUKrjpdPDQvK2a\",\"friendlyName\":\"Operator_TX061AEI\",\"UDN\":\"608fef11-2800-482a-962b-23a6690c93c1\"}"
}
```

**JSON-RPC:**

Request:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "SecondScreen.onLaunchRequest",
  "params": {
    "listen": true
  }
}
```

Response:

```
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "type": "dial",
    "version": "1.7",
    "data": "{\"code\":\"AQDPQZiQcb3KQ7gY7yy5tHTMbbkGHR9Zjp-KL53H3eKBZIeAt7O9UKYPu6B21l2UZVmIqkFXDXBmXvK4g2e3EgZtjMNmKPsTltgnRl95DImtOXjSpWtTjSaOkW4w1kZKUTwLKdwVWTzBVH8ERHorvLU6vCGOVHxXt65LNwdl5HKRweShVC1V9QsyvRnQS61ov0UclmrH_xZML2Bt-Q-rZFjey5MjwupIb4x4f53XUJMhjHpDHoIUKrjpdPDQvK2a\",\"friendlyName\":\"Operator_TX061AEI\",\"UDN\":\"608fef11-2800-482a-962b-23a6690c93c1\"}"
  }
}
```

---

## Types