title: Accessibility

version: 0.8.1
layout: default
sdk: core

# Accessibility Module

Version 0.8.1

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.

Table of Contents

• Accessibility Module
  • Overview
  • OpenRPC
  • Table of Contents
  • Usage
  • Methods
    • closedCaptions
    • closedCaptionsSettings
    • listen
    • once
    • voiceGuidance
    • voiceGuidanceSettings
  • Events
    • Additional events
  • Schemas
    • ClosedCaptionsStyles
    • ClosedCaptionsSettings
    • 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:

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"
  }
}

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

{
  "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:

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"
  }
}

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

{
  "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:

Promise resolution:

Callback parameters:

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"
  }
}

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

{
  "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:

Promise resolution:

Callback parameters:

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:

Callback parameters:

Promise resolution:

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:

Promise resolution:

Callback parameters:

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:

Callback parameters:

Promise resolution:

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:

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
}

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

{
  "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:

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
}

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

{
  "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:

Promise resolution:

Callback parameters:

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
}

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

{
  "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.

Schemas

ClosedCaptionsStyles

The default styles to use when displaying closed-captions

type ClosedCaptionsStyles = {
  fontFamily?: string
  fontSize?: number
  fontColor?: string
  fontEdge?: string
  fontEdgeColor?: string
  fontOpacity?: number
  backgroundColor?: string
  backgroundOpacity?: number
  textAlign?: string
  textAlignVertical?: string
}

ClosedCaptionsSettings

type ClosedCaptionsSettings = {
  enabled: boolean               // Whether or not closed-captions should be enabled by default
  styles: ClosedCaptionsStyles   // The default styles to use when displaying closed-captions
}

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
}