qualtrics_barebones_question_for_lif.js

/**
 * 
 * Qualtrics_barebones_question_for_lif.js
 * Javascript code to integrate Streamingbandit & Qualtrics.
 * Sends an receives JSON to and from StreamingBandit server
 *
 **/

/* --- insert as <script> into look and feel ---*/

function createRequest() {
    var result = null;
    if (window.XMLHttpRequest) {
	result = new XMLHttpRequest();
	if (typeof result.overrideMimeType != 'undefined') {
	    result.overrideMimeType('application/json');
	}
    } else if (window.ActiveXObject) {
	result = new ActiveXObject("Microsoft.XMLHTTP");
    } else {
	// No known mechanism -- consider aborting the application
    }
    return result;
}

/* --- end </script> ---*/

/* --- insert into Question JS ---*/

Qualtrics.SurveyEngine.addOnload(function() {

    /* ------------------------------------------- question settings ------------------------------------*/

    // Send result previous question, change QID accordingly

    var selectedChoice = '${q://QID15/ChoiceTextEntryValue}';
    var selectedChoiceStr = String(selectedChoice);
    var reqPrev = createRequest();
    reqPrev.open("GET",
        selectedChoiceStr,
        true);
    reqPrev.send();


    /* ------------------------------------------- survey settings --------------------------------------*/

    strmID = 1;
    strmKey = "36c067b1d3";
    ServerURL = "https://strm.mnds.org:8080/"
    qPreNr = 5555

    x0 = 259

    // Select position in table of adaptive field for the current question

    roundToFixed = 0;

    /* ------------------------------------------- custom code ------------------------------------------*/

    QualtricsQID = document.querySelector('.QuestionOuter').id;
    questionNumber = qPreNr + QualtricsQID.substring(3)

    answerID = "QR~" + QualtricsQID


    var req = createRequest();

    req.onreadystatechange = function() {
        if (req.readyState != 4) return; // Not there yet
        if (req.status != 200) {
            // Handle request failure here...
            return;
        }
        var resp = req.responseText;
        var parsedJSON = eval('(' + resp + ')');
        var xvalue = parsedJSON.action.x;
        var tvalue = parsedJSON.action.t;

        var QuestionBody = document.getElementsByClassName('QuestionBody')[0];
        var imgTags = QuestionBody.getElementsByTagName('img');
        var firstImg = imgTags[0];
        firstImg.setAttribute("style", "height:" + xvalue.toFixed(roundToFixed) + "px; width:100px;");

        document.getElementById("Questions").style.display = "block";
        document.getElementById("Buttons").style.display = "block";

        var radios = document.getElementsByName('size');

        for (var i = 0, len = radios.length; i < len; i++) {
            radios[i].onclick = function() {
                rvalue = this.value /* ADAPTIVE! */
                answerURL = ServerURL + strmID + '/setReward.json?key=' + strmKey + '&action={%22x%22:' + xvalue + ',%22t%22:' + tvalue + '}&reward=' + rvalue + '&context={%22question%22:' + questionNumber + ',%22x0%22:' + x0 + '}'
                    // Set text field to URL to be send in next question 
                document.getElementById(answerID).value = answerURL;
            };
        }
    }


    req.open("GET",
        ServerURL + strmID + "/getAction.json?key=" + strmKey + "&context={%22question%22:" + questionNumber + ",%22x0%22:" + x0 + "}",
        true);

    req.send();


    /* ------------------------------------------- custom code ------------------------------------------*/

});

/* --- end Question JS ---*/