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JavaScript jQuery Basics (2014) Creating a Simple Drawing Application Perfect

Anthony Ho
Anthony Ho
10,228 Points
Posted by Anthony Ho
Anthony Ho
10,228 Points

I want to use the slider to change the thickness of the brush

This is what I got so far, but it doesn't work:

function changeThickness(){
var x = $("#thickness).val();

context.lineWidth = x;

}

$("input[type=range]").on("input", changeThickness);

2 Answers

Chad Dugas
PLUS
Chad Dugas
Courses Plus Student 13,304 Points
Chad Dugas
Chad Dugas
Courses Plus Student 13,304 Points

You need to do something like this:

$("#thickness").on("input", function() {
    context.lineWidth = $("#thickness").val();
});

  context.lineCap = "round";

And your HTML should look something like this:

<p>
    <label for="thickness">Thickness</label>
    <input id="thickness" name="thickness" type="range" min=1 max=50 value=1>
</p>

You can replace your whole function with that. Also you need to make the lineCap = "round". If you don't then the thick line you draw will be a collection of tiny lines. You can put that part anywhere in your program. It doesn't need to be inside a function or event.

Anthony Ho
Anthony Ho
10,228 Points
Anthony Ho
Anthony Ho
10,228 Points

Thanks a lot. Right now I'm trying to change the cursor for only the rubber. Here is what I got so far:

if($(".rubber").contains("selected")){
$canvas.css({"cursor": "none"});
 $canvas.css({"cursor": "url(../img/eraser.png)"});   

}
Chad Dugas
Chad Dugas
Courses Plus Student 13,304 Points
Chad Dugas
Chad Dugas
Courses Plus Student 13,304 Points

I'm not totally sure I understand what you are trying to do, but I think you should try using the jQuery method .hasClass.

So your code would look like this:

if($(".rubber").hasClass("selected")){
    $canvas.css({"cursor": "none"});
    $canvas.css({"cursor": "url(../img/eraser.png)"});   
}

Also, I don't think you need you need to set the cursor to none, then assign it to the eraser image. You could probably omit that first line so it becomes:

if($(".rubber").hasClass("selected")){
    $canvas.css({"cursor": "url(../img/eraser.png)"});   
}
Andrew Chalkley
STAFF
Andrew Chalkley
Treehouse Guest Teacher
Andrew Chalkley
Andrew Chalkley
Treehouse Guest Teacher

"#thickness You're missing a " at the end :)

Anthony Ho
Anthony Ho
10,228 Points
Anthony Ho
Anthony Ho
10,228 Points

still doesn't work though Please give me some hints. I appreciate it.