XML Flash Quiz - manipulating xml data

[babeinwoods]

Hello,

As my handle suggests, Flash, XML and Actionscripting are pretty much a foreign language for me, so any help I can get with this issue would be immensely appreciated.

I found a tutorial online on creating a flash quiz application, using xml data for the questions. The quiz works fine - I even managed to add a countdown timer and randomize the questions. BUT... I need to be able to have 50 questions in the xml file, and only import 15 random questions to the flash file. How do I do that?

Can anyone help?

Lost in the Woods

[glosrfc]

The simplest way would be to import all 50 questions from your XML file, place them into an array, randomise the array, then read the first 15 items.

This example uses an external text file, but the principle is still the same:
http://www.kirupa.com/forum/showthread.php?t=337408

Other examples and clarification:
http://www.kirupa.com/forum/showthread.php?p=2414453
http://www.kirupa.com/forum/showthread.php?t=307291
http://www.kirupa.com/forum/showthread.php?t=331116

[babeinwoods]

Hey GlosRFC,

I'm still going through the links you posted, so I can't boast success as yet, but thank you for the quick reply. I appreciate it.

babeinwoods

[babeinwoods]

No luck!

I'm trying various ways to do this, and have spent two days going through various tutorials, books and the Flash Help section, but if I get one thing right, the other goes wrong - for instance, if I specify how many questions to be shown, the movie doesn't show the questions at all! If I shuffle them, it loads all the questions... With one attempt I just kept getting 'undefined parameter'. Can I share the code and get help? Here it is:

function QuizItem(question)
{
    this.question=question;
    this.answers=new Array();
    this.numOfAnswers=0;
    this.correctAnswer=0;
    this.getQuestion=function()
    {
        return this.question;
    }
    this.addAnswer=function(answer, isCorrectAnswer)
    {
        this.answers[this.numOfAnswers]=answer;
        if (isCorrectAnswer)
            this.correctAnswer=this.numOfAnswers;
        this.numOfAnswers++;
    }

    this.getAnswer=function(answerNumberToGet)
    {
        return this.answers[answerNumberToGet];
    }
    
    this.getCorrectAnswerNumber=function()
    {
        return this.correctAnswer;
    }
    
    this.checkAnswerNumber=function(userAnswerNumber)
    {
        if (userAnswerNumber==this.getCorrectAnswerNumber())
            gotoAndPlay("Correct");
        else
            gotoAndPlay("Wrong");
    }
}

function onQuizData(success)
{
    var quizNode=this.firstChild;
    var quizTitleNode=quizNode.firstChild;    
    title=quizTitleNode.firstChild.nodeValue;
    
    var i=0;
    // <items> follows <title>
    var itemsNode=quizNode.childNodes[1];
    while (itemsNode.childNodes[i])
    {
        var itemNode=itemsNode.childNodes[i];
        // <item> consists of  <question> and one or more <answer>
        // <question> always comes before <answer>s (node 0 of <item>)
        var questionNode=itemNode.childNodes[0];
        quizItems[i]=new QuizItem(questionNode.firstChild.nodeValue);
        var a=1;        
        // <answer> follows <question>
        var answerNode=itemNode.childNodes[a++];
        while (answerNode)
        {
            var isCorrectAnswer=false;
            if (answerNode.attributes.correct=="y")
                isCorrectAnswer=true;
            quizItems[i].addAnswer(answerNode.firstChild.nodeValue, isCorrectAnswer);
            // goto the next <answer>
            answerNode=itemNode.childNodes[a++];
        }
        i++;
    }

     function randList(max:Number, num:Number, shuffled:Boolean):Array {  
     var tempArray:Array = [];  
     for (i = 0; i < max && num > 0; ++i) {  
      if (Math.floor(Math.random() * (max - i)) < num) {  
       tempArray.push(i + 1);  
       num--;  
      }  
     }  
     if (shuffled) {  
     tempArray.sort(function () {  
      return Math.floor(Math.random() * 2) ? true : false;  
     });  
    }  
    return (tempArray);  
   }  
    
    gotoAndStop("Start");
}

var quizItems=new Array(); 
var myData=new XML();
myData.ignoreWhite=true;
myData.onLoad=onQuizData;
myData.load("quiz.xml");

stop();

This code has a shuffle function, and I am supposed to add "var myArr:Array = randList(50, 15, true)" somewhere on the timeline, but when I do, the questions don't load. Without it, everything works smoothly, except the shuffle itself.

Also, on the timeline, this is the code:

if (currentQuestionNumber>quizItems.length)
   gotoAndStop("SummaryScreen");
 
var currentQuizItem=quizItems[currentQuestionNumber-1];
var hasAnswered=false;
question=currentQuizItem.getQuestion();
for (var i=1; i<=4; i++)
{
    _root["answer"+i]=currentQuizItem.getAnswer(i-1);
}

stop();

I'd really appreciate any help in getting this to work. Again, I'd like to have 50 questions, out of which each session of game play would only display 15 random questions.

[babeinwoods]

I GOT IT!

Who'd have thought? All it took was wading through flash.livedocs and learning all about arrays.

Still a babe in the woods.