Display APL visuals through LaunchRequestHandler and HelpIntentHandler

Not all devices can react to a render directive. For example, consider an Echo Dot, which doesn't have a screen. If you return a RenderDocument directive, your skill session might crash.

This means that for an Alexa-enabled device to render your APL document safely, you must implement a response with a render directive.

This directive takes the form of Alexa.Presentation.APL.RenderDocument. So, by using this directive, you must ensure that the calling device validates that it supports APL.

Before you create the response in your LaunchRequestHandler.handle() add a check to see if the skill request payload contains the APL interface. The following example shows how you can check the payload:

if (Alexa.getSupportedInterfaces(handlerInput.requestEnvelope)['Alexa.Presentation.APL']) {
    // Create render directive
}

The if-statement checks whether the APL interface is sent in the request envelope. You must only add the response after you know that the device supports APL.

To add a directive by using the Node.js SDK, inside that if-statement you must call:

handlerInput.responseBuilder.addDirective({…});

You will then have to reference the APL document in your backend and enter the data-sources object.

Focusing on the LaunchRequestHandler of the Tic-Tac-Toe skill and its Welcome screen, the if-statement and the render directive are the following:

if (Alexa.getSupportedInterfaces(handlerInput.requestEnvelope)['Alexa.Presentation.APL']) {
    handlerInput.responseBuilder.addDirective({
    type: 'Alexa.Presentation.APL.RenderDocument',
    document: informationDocument,
    datasources: {
	  information: {
		backgroundImage: {
		    url: "https://d3j5530a0cofat.cloudfront.net/adlc/background.png",
		    colorOverlay: true
		},
		logoUrl: "https://d3j5530a0cofat.cloudfront.net/adlc/somelogo.png",
		textContent: {
		    primaryText: "Welcome to Tic-Tac-Toe!",
		    secondaryText: "",
		    hintText: "Try, \"Alexa, top row, left column\", or \"Alexa, help\""
		}
	  }
	}
    });            
}

The general process is the following:

Set type: 'Alexa.Presentation.APL.RenderDocument'.
Use the document attribute of the directive.
Apply all the data sources to the data sources parameter of the directive as typical JSON.
Apply the same general mechanism to all screens in your skill.

Exercise 1

Update the HelpIntentHandler to display the Help screen by using the same APL document as above.

Assume that index.js contains the following code:

const informationDocument = require('./documents/InformationDocument.json');

Use the following elements:

Background image: https://d3j5530a0cofat.cloudfront.net/adlc/background.png
Logo image: https://d3j5530a0cofat.cloudfront.net/adlc/somelogo.png
Primary text: Say the row and then the column, "cross", "circle", or "board status"
Secondary text: ""
Footer text: Try "Alexa, middle row, center column" or "Alexa, circle"

InformationDocument.json

{
    "type": "APL",
    "version": "1.7",
    "theme": "dark",
    "import": [
        {
            "name": "alexa-layouts",
            "version": "1.4.0"
        }
    ],
    "mainTemplate": {
        "parameters": [
            "information"
        ],
        "items": [
            {
                "type": "AlexaHeadline",
                "id": "informationScreen",
                "backgroundImageSource": "${information.backgroundImage.url}",
                "backgroundColorOverlay": "${information.backgroundImage.colorOverlay}",
                "headerAttributionImage": "${information.logoUrl}",
                "primaryText": "${information.textContent.primaryText}",
                "secondaryText": "${information.textContent.secondaryText}",
                "footerHintText": "${information.textContent.hintText}"
            }
        ]
    }
}

HelpIntentHandler.js

const HelpIntentHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest'
            && Alexa.getIntentName(handlerInput.requestEnvelope) === 'AMAZON.HelpIntent';
    },
    handle(handlerInput) {
        const speakOutput = `You can place your mark by saying the row, and then the column. Say cross or circle anytime to change your mark, or board status and I will tell you where all the marks are.`;

        return handlerInput.responseBuilder
            .speak(speakOutput)
            .reprompt(speakOutput)
            .getResponse();
    }
};

Solution

const HelpIntentHandler = {
    canHandle(handlerInput) {
        return Alexa.getRequestType(handlerInput.requestEnvelope) === 'IntentRequest'
            && Alexa.getIntentName(handlerInput.requestEnvelope) === 'AMAZON.HelpIntent';
    },
    handle(handlerInput) {
        const speakOutput = `You can place your mark by saying the row, and then the column. Say cross or circle anytime to change your mark, or board status and I will tell you where all the marks are.`;

        if (Alexa.getSupportedInterfaces(handlerInput.requestEnvelope)['Alexa.Presentation.APL']) {
            handlerInput.responseBuilder.addDirective({
            type: 'Alexa.Presentation.APL.RenderDocument',
            document: informationDocument,
            datasources: {
        	  information: {
        		backgroundImage: {
        		    url: "https://d3j5530a0cofat.cloudfront.net/adlc/background.png",
        		    colorOverlay: true
        		},
        		logoUrl: "https://d3j5530a0cofat.cloudfront.net/adlc/somelogo.png",
        		textContent: {
        		    primaryText: "Say the row and then the column, \"cross\", \"circle\", or \"board status\"",
        		    secondaryText: "",
        		    hintText: "Try \"Alexa, middle row, center column\" or \"Alexa, circle\""
        		}
        	  }
        	}
            });            
        }

        return handlerInput.responseBuilder
            .speak(speakOutput)
            .reprompt(speakOutput)
            .getResponse();
    }
};

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