Accessibility Module

Version 0.9.0

Overview

The Accessibility module provides access to the user/device settings for closed captioning and voice guidance.

Apps SHOULD attempt o respect these settings, rather than manage and persist seprate settings, which would be different per-app.

OpenRPC

Firebolt APIs are maintained in the rdkcentral/firebolt-core-sdk GitHub repository.

You can see this API in the accessibility.json OpenRPC JSON-Schema document.

Overview
OpenRPC
Usage
Methods
Events
- Additional Events
Schemas
- VoiceGuidanceSettings

Usage

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

import { Accessibility } from '@firebolt-js/sdk'

Methods

closedCaptions

This API is deprecated since version 0.6.0. Use Accessibility.closedCaptionsSettings() instead.

Get the user’s preferred closed-captions settings

function closedCaptions(): Promise<ClosedCaptionsSettings>

Promise resolution:

Type	Description
`ClosedCaptionsSettings`	the closed captions settings

Examples

Getting the closed captions settings

JavaScript:

import { Accessibility } from '@firebolt-js/sdk'

Accessibility.closedCaptions()
    .then(closedCaptionsSettings => {
        console.log(closedCaptionsSettings)
    })

Value of closedCaptionsSettings:

{
  "enabled": true,
  "styles": {
    "fontFamily": "Monospace sans-serif",
    "fontSize": 1,
    "fontColor": "#ffffff",
    "fontEdge": "none",
    "fontEdgeColor": "#7F7F7F",
    "fontOpacity": 100,
    "backgroundColor": "#000000",
    "backgroundOpacity": 100,
    "textAlign": "center",
    "textAlignVertical": "middle"
  }
}

JSON-RPC:

Request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "accessibility.closedCaptions",
  "params": {}
}

Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "enabled": true,
    "styles": {
      "fontFamily": "Monospace sans-serif",
      "fontSize": 1,
      "fontColor": "#ffffff",
      "fontEdge": "none",
      "fontEdgeColor": "#7F7F7F",
      "fontOpacity": 100,
      "backgroundColor": "#000000",
      "backgroundOpacity": 100,
      "textAlign": "center",
      "textAlignVertical": "middle"
    }
  }
}

closedCaptionsSettings

Get the user’s preferred closed-captions settings

To get the value, call the method with no parameters:

function closedCaptionsSettings(): Promise<ClosedCaptionsSettings>

Promise resolution:

Type	Description
`ClosedCaptionsSettings`	the closed captions settings

Examples

Getting the closed captions settings

JavaScript:

import { Accessibility } from '@firebolt-js/sdk'

Accessibility.closedCaptionsSettings()
    .then(closedCaptionsSettings => {
        console.log(closedCaptionsSettings)
    })

Value of closedCaptionsSettings:

{
  "enabled": true,
  "styles": {
    "fontFamily": "Monospace sans-serif",
    "fontSize": 1,
    "fontColor": "#ffffff",
    "fontEdge": "none",
    "fontEdgeColor": "#7F7F7F",
    "fontOpacity": 100,
    "backgroundColor": "#000000",
    "backgroundOpacity": 100,
    "textAlign": "center",
    "textAlignVertical": "middle"
  }
}

JSON-RPC:

Request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "accessibility.closedCaptionsSettings",
  "params": {}
}

Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "enabled": true,
    "styles": {
      "fontFamily": "Monospace sans-serif",
      "fontSize": 1,
      "fontColor": "#ffffff",
      "fontEdge": "none",
      "fontEdgeColor": "#7F7F7F",
      "fontOpacity": 100,
      "backgroundColor": "#000000",
      "backgroundOpacity": 100,
      "textAlign": "center",
      "textAlignVertical": "middle"
    }
  }
}

To subscribe to notifications when the value changes, pass a function as the only parameter:

function closedCaptionsSettings(subscriber: (closedCaptionsSettings: ClosedCaptionsSettings) => void): Promise<boolean>

Parameters:

Param	Type	Required	Summary
`subscriber`	`Function`	Yes	A callback that gets invoked when the value for closedCaptionsSettings changes

Promise resolution:

Type	Summary
`listenerId`	The id of the listener that can be used with Accessibility.clear(listenerId) to unsubscribe

Callback parameters:

Param	Type	Required	Summary
`closedCaptionsSettings`	`ClosedCaptionsSettings`	Yes	the closed captions settings

Examples

Getting the closed captions settings

JavaScript:

import { Accessibility } from '@firebolt-js/sdk'

Accessibility.closedCaptionsSettings(closedCaptionsSettings => {
  // property value was changed
  console.log(closedCaptionsSettings)
}).then(listenerId => {
  // you can clear this listener w/ Accessibility.clear(listenerId)
})

value of closedCaptionsSettings:

{
  "enabled": true,
  "styles": {
    "fontFamily": "Monospace sans-serif",
    "fontSize": 1,
    "fontColor": "#ffffff",
    "fontEdge": "none",
    "fontEdgeColor": "#7F7F7F",
    "fontOpacity": 100,
    "backgroundColor": "#000000",
    "backgroundOpacity": 100,
    "textAlign": "center",
    "textAlignVertical": "middle"
  }
}

JSON-RPC:

Request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "accessibility.onClosedCaptionsSettingsChanged",
  "params": {
    "listen": true
  }
}

Response:

{
  "jsonrpc": "2.0",
  "id": "1",
  "result": {
    "listening": "true"
  }
}

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "enabled": true,
    "styles": {
      "fontFamily": "Monospace sans-serif",
      "fontSize": 1,
      "fontColor": "#ffffff",
      "fontEdge": "none",
      "fontEdgeColor": "#7F7F7F",
      "fontOpacity": 100,
      "backgroundColor": "#000000",
      "backgroundOpacity": 100,
      "textAlign": "center",
      "textAlignVertical": "middle"
    }
  }
}

listen

Listen for events from this module.

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

Accessibility.listen(event: string, (data: any) => void): Promise<number>

Parameters:

Param	Type	Required	Summary
`event`	`string`	Yes	The event to listen for, see 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. `Accessibility.clear(id)`

Callback parameters:

Param	Type	Required	Summary
`data`	`any`	Yes	The event data, which depends on which event is firing, see Events.

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

Accessibility.listen((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.

Callback parameters:

Param	Type	Required	Summary
`event`	`string`	Yes	The event that has occured listen for, see Events.
`data`	`any`	Yes	The event data, which depends on which event is firing, see Events.

Promise resolution:

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

See Listening for events for more information and examples.

once

Listen for only one occurance of an event from this module. The callback will be cleared after one event.

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

Accessibility.once(event: string, (data: any) => void): Promise<number>

Parameters:

Param	Type	Required	Summary
`event`	`string`	Yes	The event to listen for, see 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. `Accessibility.clear(id)`

Callback parameters:

Param	Type	Required	Summary
`data`	`any`	Yes	The event data, which depends on which event is firing, see Events.

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

Accessibility.once((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.

Callback parameters:

Param	Type	Required	Summary
`event`	`string`	Yes	The event that has occured listen for, see Events.
`data`	`any`	Yes	The event data, which depends on which event is firing, see Events.

Promise resolution:

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

See Listening for events for more information and examples.

voiceGuidance

This API is deprecated since version 0.6.0. Use Accessibility.voiceGuidanceSettings() instead.

Get the user’s preferred voice guidance settings

function voiceGuidance(): Promise<VoiceGuidanceSettings>

Promise resolution:

Type	Description
`VoiceGuidanceSettings`	the voice guidance settings

Examples

Getting the voice guidance settings

JavaScript:

import { Accessibility } from '@firebolt-js/sdk'

Accessibility.voiceGuidance()
    .then(settings => {
        console.log(settings)
    })

Value of settings:

{
  "enabled": true,
  "speed": 5
}

JSON-RPC:

Request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "accessibility.voiceGuidance",
  "params": {}
}

Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "enabled": true,
    "speed": 5
  }
}

voiceGuidanceSettings

Get the user’s preferred voice guidance settings

To get the value, call the method with no parameters:

function voiceGuidanceSettings(): Promise<VoiceGuidanceSettings>

Promise resolution:

Type	Description
`VoiceGuidanceSettings`	the voice guidance settings

Examples

Getting the voice guidance settings

JavaScript:

import { Accessibility } from '@firebolt-js/sdk'

Accessibility.voiceGuidanceSettings()
    .then(settings => {
        console.log(settings)
    })

Value of settings:

{
  "enabled": true,
  "speed": 5
}

JSON-RPC:

Request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "accessibility.voiceGuidanceSettings",
  "params": {}
}

Response:

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "enabled": true,
    "speed": 5
  }
}

To subscribe to notifications when the value changes, pass a function as the only parameter:

function voiceGuidanceSettings(subscriber: (settings: VoiceGuidanceSettings) => void): Promise<boolean>

Parameters:

Param	Type	Required	Summary
`subscriber`	`Function`	Yes	A callback that gets invoked when the value for voiceGuidanceSettings changes

Promise resolution:

Type	Summary
`listenerId`	The id of the listener that can be used with Accessibility.clear(listenerId) to unsubscribe

Callback parameters:

Param	Type	Required	Summary
`settings`	`VoiceGuidanceSettings`	Yes	the voice guidance settings

Examples

Getting the voice guidance settings

JavaScript:

import { Accessibility } from '@firebolt-js/sdk'

Accessibility.voiceGuidanceSettings(settings => {
  // property value was changed
  console.log(settings)
}).then(listenerId => {
  // you can clear this listener w/ Accessibility.clear(listenerId)
})

value of settings:

{
  "enabled": true,
  "speed": 5
}

JSON-RPC:

Request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "accessibility.onVoiceGuidanceSettingsChanged",
  "params": {
    "listen": true
  }
}

Response:

{
  "jsonrpc": "2.0",
  "id": "1",
  "result": {
    "listening": "true"
  }
}

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "enabled": true,
    "speed": 5
  }
}

Events

Additional events

The following events are documented as part of a related set of method APIs.

For more information, follow the links under the “Documentation” column.

JavaScript	RPC	Payload	Documentation
closedCaptionsSettingsChanged	onClosedCaptionsSettingsChanged	ClosedCaptionsSettings	closedCaptionsSettings
voiceGuidanceSettingsChanged	onVoiceGuidanceSettingsChanged	VoiceGuidanceSettings	voiceGuidanceSettings

Schemas

VoiceGuidanceSettings

type VoiceGuidanceSettings = {
  enabled: boolean              // Whether or not voice guidance should be enabled by default
  speed: number                 // The speed at which voice guidance speech will be read back to the user
}

Go To Top

Accessibility Module

Overview

OpenRPC

Table of Contents

Usage

Methods

closedCaptions

closedCaptionsSettings

listen

once

voiceGuidance

voiceGuidanceSettings

Events

Additional events

Schemas

VoiceGuidanceSettings