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CSS jQuery Basics (2014) Creating a Simple Drawing Application Using on()

Daniel Hildreth
Daniel Hildreth
16,170 Points
Posted by Daniel Hildreth
Daniel Hildreth
16,170 Points

Using .on() in jQuery

I need help with one of the code challenges in the jQuery courses when you use the .on syntax rather than the .click syntax. My code is the same as what we did in the videos, and it looks solid, but it doesn't work. Can someone help me figure out why?

js/app.js 
//Problem: No user interaction causes no change to application
//Solution: When user interacts cause changes appropriately
var color = $(".selected").css("background-color");

//When clicking on control list items
$(".controls").on("click", "li" function(){
  //Deselect sibling elements
  $(this).siblings().removeClass("selected");
  //Select clicked element
  $(this).addClass("selected");
  //cache current color
  color = $(this).css("background-color");
});

//When "New Color" is pressed
$("#revealColorSelect").click(function(){
  //Show color select or hide the color select
  changeColor();
  $("#colorSelect").toggle();
});

//update the new color span
function changeColor() {
  var r = $("#red").val();
  var g = $("#green").val();
  var b = $("#blue").val();
  $("#newColor").css("background-color", "rgb(" + r + "," + g +", " + b + ")");
}

//When color sliders change
$("input[type=range]").change(changeColor);

//When "Add Color" is pressed
$("#addNewColor").click(function(){
  //Append the color to the controls ul
  var $newColor = $("<li></li>");
  $newColor.css("background-color", $("#newColor").css("background-color"));
  $(".controls ul").append($newColor);
  //Select the new color
  $newColor.click();
});

//On mouse events on the canvas
  //Draw lines
index.html 
<!DOCTYPE html>
<html>
<head>
    <title>Simple Drawing Application</title>
    <link rel="stylesheet" href="css/style.css" type="text/css" media="screen" title="no title" charset="utf-8">
</head>
<body>
    <canvas width="600" height="400"></canvas>
    <div class="controls">
        <ul>
            <li class="red selected"></li>
            <li class="blue"></li>
            <li class="yellow"></li>
        </ul>
        <button id="revealColorSelect">New Color</button>
        <div id="colorSelect">
            <span id="newColor"></span>
            <div class="sliders">
                <p>
                    <label for="red">Red</label>
                    <input id="red" name="red" type="range" min=0 max=255 value=0>
                </p>
                <p>
                    <label for="green">Green</label>
                    <input id="green" name="green" type="range" min=0 max=255 value=0>
                </p>
                <p>
                    <label for="blue">Blue</label>
                    <input id="blue" name="blue" type="range" min=0 max=255 value=0>
                </p>
            </div>
            <div>
            <button id="addNewColor">Add Color</button>
            </div>
        </div>
    </div>
    <script src="//code.jquery.com/jquery-1.11.0.min.js" type="text/javascript" charset="utf-8"></script>
    <script src="js/app.js" type="text/javascript" charset="utf-8"></script>    
</body>
</html>

2 Answers

David Beno
David Beno
10,290 Points
David Beno
David Beno
10,290 Points

You are missing a comma after "li".

Daniel Hildreth
Daniel Hildreth
16,170 Points
Daniel Hildreth
Daniel Hildreth
16,170 Points

Ok thank you David. I will try that out. I don't remember the video showing a comma had to go there though but I will re-check and verify, and also try it out.