Move JS code from HTML to source in HEAD section

Question

I have a problem, and I would like you to guide me to solve it if you do not mind ... In my HTML source code had several pieces of css codes here and there. So I decided to put together into a file called principal.css and do the following in the head section

<link href="css/principal.css" rel="stylesheet" type="text/css" />

This has worked wonderfully! My idea was to do the same with the javascript code in my HTML, but it has not worked. This is one of them:

$("[data-slider]")
    .each(function () {
    var input = $(this);
    $("<span>")
        .addClass("output")
            .insertAfter($(this));
    })
    .bind("slider:ready slider:changed", function (event, data) {
    $(this)
        .nextAll(".output:first")
            .html(data.value);
    });

Is there some special way to do this? My goal is that the page has the least amount of code, I leave well indented, documented and clean. Greetings, I will await your answers in! Please, excuse my english...

Answer 1

You need to wrap this in $(document).ready(...)

Also, it has unusual indentation. It would probably be better to format it like this:

$(document).ready(function() {
    $("[data-slider]").each(function () {
        var input = $(this);
        $("<span>").addClass("output").insertAfter($(this));
    }).bind("slider:ready slider:changed", function (event, data) {
        $(this).nextAll(".output:first").html(data.value);
    });

});

I personally don't like chaining so many commands like this in a row. It might be SLIGHTLY more efficient, but it makes it much more difficult to debug and fix problems. I personally would break the .each() and the .bind() into separate statements. But I suppose it's a matter of preference.

Answer 2

.ready() documentation

$(document).ready(function(){
    // your code here
});

or

.load() documentation

$(window).on('load', function(){
    // your code here
});

Answer 3

Place your js code in a separate .js file. Similar to how CSS is also placed in a separate file and then link it to your html file.

like so, in your html file:

<script src="somejsfile.js"></script>

And yes, you have to wrap your js code in a document.ready function so it can execute when the documents elements are finished loading.

For example:

$(document).ready(function() {
    // Your JS code here
});

This is because the browsers HTML interpreter reads code from TOP to BOTTOM, so if your not setting a document.ready, the JavaScript will run before any of your document elements are loaded.