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JavaScript jQuery Basics (2014) Creating a Simple Drawing Application Using siblings(), removeClass() and addClass()

Posted by bradley maybee
bradley maybee
5,249 Points

no idea how to finish this

so lost can someone help?

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 li").click(function(){
  //Deselect sibling elements
  $(this);
  //Select clicked element
  $(this);
  //cache current color
  color = $(this).css("background-color");
});

//When new color is pressed
  //Show color select or hide the color select

//When color sliders change
  //update the new color span

//When add color is pressed
  //Append the color to the controls ul
  //Select the new color

//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>

1 Answer

rydavim
rydavim
18,813 Points
rydavim
rydavim
18,813 Points

Challenge Stage One: The .siblings() method will allow you to select the neighbors. You can chain this method onto the code they've provided. You can read more information about this method in the jQuery documentation.

Challenge Stage Two: What method might you be able to use to remove a class? Try looking at the Attributes page in the jQuery documentation.

Challenge Stage Three: Is there a method similar to the one you used in stage two? Try looking at the Attributes page in the jQuery documentation.

Please let me know if you run into any snags, and we can walk through a solution. Happy coding! :)

Chris Mason
.a{fill-rule:evenodd;}techdegree seal-36
Chris Mason
Full Stack JavaScript Techdegree Graduate 24,526 Points

This is an excellent explanation & instruction.