html - jQuery on window resize

Question

I have the following JQuery code:

$(document).ready(function () {
    var $containerHeight = $(window).height();
    if ($containerHeight <= 818) {
        $('.footer').css({
            position: 'static',
            bottom: 'auto',
            left: 'auto'
        });
    }
    if ($containerHeight > 819) {
        $('.footer').css({
            position: 'absolute',
            bottom: '3px',
            left: '0px'
        });
    }
});

The only problem is that this only works when the browser first loads, I want containerHeight to also be checked when they are resizing the window?

Any ideas?

Answer 1

Here's an example using jQuery, javascript and css to handle resize events.
(css if your best bet if you're just stylizing things on resize (media queries))
http://jsfiddle.net/CoryDanielson/LAF4G/

css

.footer 
{
    /* default styles applied first */
}

@media screen and (min-height: 820px) /* height >= 820 px */
{
    .footer {
        position: absolute;
        bottom: 3px;
        left: 0px;
        /* more styles */
    }
}

javascript

window.onresize = function() {
    if (window.innerHeight >= 820) { /* ... */ }
    if (window.innerWidth <= 1280) {  /* ... */ }
}

jQuery

$(window).on('resize', function(){
    var win = $(this); //this = window
    if (win.height() >= 820) { /* ... */ }
    if (win.width() >= 1280) { /* ... */ }
});

How do I stop my resize code from executing so often!?

This is the first problem you'll notice when binding to resize. The resize code gets called a LOT when the user is resizing the browser manually, and can feel pretty janky.

To limit how often your resize code is called, you can use the debounce or throttle methods from the underscore & lodash libraries.

• debounce will only execute your resize code X number of milliseconds after the LAST resize event. This is ideal when you only want to call your resize code once, after the user is done resizing the browser. It's good for updating graphs, charts and layouts that may be expensive to update every single resize event.
• throttle will only execute your resize code every X number of milliseconds. It "throttles" how often the code is called. This isn't used as often with resize events, but it's worth being aware of.

If you don't have underscore or lodash, you can implement a similar solution yourself: JavaScript/JQuery: $(window).resize how to fire AFTER the resize is completed?