Alexa.KeypadController Interface

Implement the Alexa.KeypadController interface in your Alexa skill so that users can voice-control onscreen navigation. You can voice-enable scrolling, directional pad (d-pad), selection of onscreen elements, and showing more details for elements that have focus. You can enable voice navigation on your smart TV home screens, for live TV providers, or for in streaming apps. For details about video skills, see Understand the Video Skill API.

For the list of languages that the KeypadController interface supports, see List of Alexa Interfaces and Supported Languages.

Utterances

When you use the Alexa.KeypadController interface, the voice interaction model is already built for you. After the customer says one of the following utterances, Alexa sends a corresponding directive to your skill.

The following examples show some customer utterances:

Alexa, scroll right.
Alexa, page down.
Alexa, go right.
Alexa, move down.
Alexa, select this.
Alexa, go back.
Alexa, choose this.
Alexa, show details.
Alexa, show info.
Alexa, see more information.

Scenarios

Consider the following scenarios where you might use Alexa.KeypadController.

Voice-enable your home screen

If you're a manufacturer of a smart TV, you can use KeypadController to voice-enable the home screen. When the user views the list of apps that the TV supports, the user can use their voice to scroll right, left, up, or down, and to select the app of their choice. This scenario also uses the Alexa.PowerController and Alexa.Launcher interfaces. The following is an example of user utterances for this scenario:

Alexa, turn on the TV.
Alexa, scroll right.
Alexa, launch [app].

Voice-enable your channel guide

If you're a live TV provider, you can use KeypadController to voice-enable the channel guide. The user can use their voice to scroll up, down, right, or left through the guide, and to select a program. This scenario also uses the Alexa.PowerController and Alexa.Launcher interfaces. The following is an example of user utterances for this scenario:

Alexa, turn on [name of live TV provider].
Alexa, go to cable guide.
Alexa, scroll down.
Alexa, select this.
Alexa, go home.

Voice-enable your app

If you're an app developer, you might use Alexa.KeypadController to voice-enable your app to let the user use their voice to scroll up, down, right, or left. The user can use voice to see more information about an onscreen element by opening the details page, and to navigate back to the previous screen. This scenario also uses the Alexa.Launcher interface and the Alexa.RemoteVideoPlayer interface to display comedies. The following is an example of user utterances for this scenario:

Alexa, launch [app].
Alexa, show me comedies.
Alexa, scroll right.
Alexa, show me details.
Alexa, go back.

Properties and objects

Keystroke property

The Alexa.KeypadController interface uses the keystroke property as the primary property. The following are the valid values.

Keystroke type Keystroke values Description
Directional pad
(d-pad)		 UP, DOWN, LEFT, RIGHT, SELECT Move up, down, left, or right one unit or to the next onscreen element, or select the element or item that has focus.
Scrolling PAGE_UP, PAGE_DOWN, PAGE_LEFT, PAGE_RIGHT Scroll in the specified direction.
Information INFO, MORE Display more information about the onscreen element that has focus. For example, show content that's offscreen, or jump to a detail page.
Back button BACK Simulate the behavior of the back button on the remote control. For example, navigate back to the previous screen.

Discovery

You describe endpoints that support Alexa.KeypadController using the standard discovery mechanism described in Alexa.Discovery.

For the KeypadController interface, include a keys attribute and list the keystrokes that you support.

Discover response example

The following example shows a Discover.Response message for a device that supports the Alexa.KeypadController.

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{
  "event": {
    "header": {
      "namespace": "Alexa.Discovery",
      "name": "Discover.Response",
      "payloadVersion": "3",
      "messageId": "<message id>"
    },
    "payload": {
      "endpoints": [
        {
          "endpointId": "<unique ID of the endpoint>",
          "manufacturerName": "<the manufacturer name of the endpoint>",
          "description": "<a description that is shown in the Alexa app>",
          "friendlyName": "<device name, displayed in the Alexa app>",
          "displayCategories": ["TV"],
          "cookie": {},
          "capabilities": [
            {
              "type": "AlexaInterface",
              "interface": "Alexa.KeypadController",
              "version": "3",
              "keys": [
                "BACK",
                "INFO", "MORE", "SELECT",
                "UP", "DOWN", "LEFT", "RIGHT",
                "PAGE_UP", "PAGE_DOWN", "PAGE_LEFT", "PAGE_RIGHT"
              ]
            },
            {
              "type": "AlexaInterface",
              "interface": "Alexa",
              "version": "3"
            }
          ]
        }
      ]
    }
  }
}

Directives

SendKeystroke directive

Support the SendKeystroke directive so that customers can scroll your content.

SendKeystroke directive payload details

Field Description Type

keystroke

The keystroke requested by the user.

String

SendKeystroke directive example

The following example illustrates a SendKeystroke directive that Alexa sends to your skill.

{
  "directive": {
    "header": {
      "namespace": "Alexa.KeypadController",
      "name": "SendKeystroke",
      "messageId": "<message id>",
      "correlationToken": "<an opaque correlation token>",
      "payloadVersion": "3"
    },
    "endpoint": {
      "scope": {
        "type": "BearerToken",
        "token": "<an OAuth2 bearer token>"
      },
      "endpointId": "<endpoint id>",
      "cookie": {}
    },
    "payload": {
      "keystroke": "SELECT"
    }
  }
}

SendKeystroke response event

If you handle a SendKeystroke directive successfully, respond with an Alexa.Response event. You can respond synchronously or asynchronously. If you respond asynchronously, include a correlation token and a scope with an authorization token.

SendKeystroke response event example

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{
  "event": {
    "header": {
      "namespace": "Alexa",
      "name": "Response",
      "messageId": "<message id>",
      "correlationToken": "<an opaque correlation token>",
      "payloadVersion": "3"
    },
    "endpoint": {
      "scope": {
        "type": "BearerToken",
        "token": "<an OAuth2 bearer token>"
      },
      "endpointId": "<endpoint id>"
    },
    "payload": {}
  }
}

SendKeystroke directive error handling

If you can't handle a SendKeystroke directive successfully, respond with an Alexa.ErrorResponse event. Use the INVALID_VALUE error type if the user requests a keystroke that your device doesn't support.