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JavaScript Object-Oriented JavaScript (2015) Practice Project Project Overview

Dongyun Cho
Dongyun Cho
2,256 Points
Posted by Dongyun Cho
Dongyun Cho
2,256 Points

My Solution unilt now

This is what I did til now as long as I know, I'll keep making it better after watching next videos. What I'm thinking is that, I'd like to use Math.floor( Math.random() * 2) this code for changing the order of two guesses, but I don't know how to do this. Can anyone help me?

quiz.js

function Quizlist(){
  this.quizes = [];
  this.score = 0;
  this.nowIndex = 0;
}

Quizlist.prototype.add = function(quiz){
  this.quizes.push(quiz);
};

var question = document.getElementById('question');
var choice0 = document.getElementById('choice0');
var choice1 = document.getElementById('choice1');
var progress = document.getElementById('progress');

Quizlist.prototype.renderInElement = function(){
  question.innerHTML = this.quizes[this.nowIndex].text;
  choice0.innerHTML = this.quizes[this.nowIndex].guessTrue;
  choice1.innerHTML = this.quizes[this.nowIndex].guessFalse;
  progress.innerHTML = 'Score : ' + this.score + ' / ' + this.quizes.length;
}

question.js

function Question(text, guessTrue, guessFalse){
  this.text=text;
  this.guessTrue = guessTrue;
  this.guessFalse = guessFalse;
}

app.js

var quizlist = new Quizlist();
var firstQuestion = new Question("what is right one", "True", "False");
var secondQuestion = new Question("what is the fruit I like" , "Apple", "Peach");
var thirdQuestion = new Question("what is what", "YEAH", "No");

quizlist.add(firstQuestion);
quizlist.add(secondQuestion);
quizlist.add(thirdQuestion);

quizlist.renderInElement();

var guess0 = document.getElementById('guess0');
var guess1 = document.getElementById('guess1');

guess0.onclick= function(){
  quizlist.score ++;
  quizlist.nowIndex ++;
  quizlist.renderInElement();
  if(quizlist.nowIndex==quizlist.quizes.length){
    alert(quizlist.score);
  }
}

guess1.onclick= function(){
  quizlist.nowIndex ++;
  quizlist.renderInElement();
  if(quizlist.nowIndex==quizlist.quizes.length){
    alert(quizlist.score);
  }
}

1 Answer

Amber Cyr
Amber Cyr
19,699 Points
Amber Cyr
Amber Cyr
19,699 Points

In the question.js file you could do something like this:

//Durstenfeld shuffle algorithm
function shuffleArray(array) {
    for (var i = array.length - 1; i > 0; i--) {
        var j = Math.floor(Math.random() * (i + 1));
        var temp = array[i];
        array[i] = array[j];
        array[j] = temp;
    }
    return array;
}

function Question(text, guess1, guess2){
    var guesses = shuffleArray([guessTrue, guessFalse]);
    this.text=text;
    this.guess1 = guesses[0];
    this.guess2 = guesses[1];
}