"'0.offsetWidth' is null or not an object" - Coda Slider - Javascript Error Question
- by bgadoci
I implemented the Coda Slider tutorial successfully that is located here: http://jqueryfordesigners.com/coda-slider-effect/
The slider works great but I am getting a javascript error that I am not sure how to fix. The error says:
'0.offsetWidth' is null or not an object
coda-slider.js, line 19 character 3
Not sure how to fix it. Anyone have any ideas? Here is my js and css (don't think I need to upload the HTML but let me know if that helps).
JS (coda-slider.js)
// when the DOM is ready...
$(document).ready(function () {
var $panels = $('#slider .scrollContainer > div');
var $container = $('#slider .scrollContainer');
// if false, we'll float all the panels left and fix the width
// of the container
var horizontal = true;
// float the panels left if we're going horizontal
if (horizontal) {
$panels.css({
'float' : 'left',
'position' : 'relative' // IE fix to ensure overflow is hidden
});
// calculate a new width for the container (so it holds all panels)
$container.css('width', $panels[0].offsetWidth * $panels.length); <------line 19
}
// collect the scroll object, at the same time apply the hidden overflow
// to remove the default scrollbars that will appear
var $scroll = $('#slider .scroll').css('overflow', 'hidden');
// apply our left + right buttons
$scroll
.before('<img class="scrollButtons left" src="/images/layout/navigation/scroll_left.png" />')
.after('<img class="scrollButtons right" src="/images/layout/navigation/scroll_right.png" />');
// handle nav selection
function selectNav() {
$(this)
.parents('ul:first')
.find('a')
.removeClass('selected')
.end()
.end()
.addClass('selected');
}
$('#slider .navigation').find('a').click(selectNav);
// go find the navigation link that has this target and select the nav
function trigger(data) {
var el = $('#slider .navigation').find('a[href$="' + data.id + '"]').get(0);
selectNav.call(el);
}
if (window.location.hash) {
trigger({ id : window.location.hash.substr(1) });
} else {
$('ul.navigation a:first').click();
}
// offset is used to move to *exactly* the right place, since I'm using
// padding on my example, I need to subtract the amount of padding to
// the offset. Try removing this to get a good idea of the effect
var offset = parseInt((horizontal ?
$container.css('paddingTop') :
$container.css('paddingLeft'))
|| 0) * -1;
var scrollOptions = {
target: $scroll, // the element that has the overflow
// can be a selector which will be relative to the target
items: $panels,
navigation: '.navigation a',
// selectors are NOT relative to document, i.e. make sure they're unique
prev: 'img.left',
next: 'img.right',
// allow the scroll effect to run both directions
axis: 'xy',
onAfter: trigger, // our final callback
offset: offset,
// duration of the sliding effect
duration: 500,
// easing - can be used with the easing plugin:
// http://gsgd.co.uk/sandbox/jquery/easing/
easing: 'swing'
};
// apply serialScroll to the slider - we chose this plugin because it
// supports// the indexed next and previous scroll along with hooking
// in to our navigation.
$('#slider').serialScroll(scrollOptions);
// now apply localScroll to hook any other arbitrary links to trigger
// the effect
$.localScroll(scrollOptions);
// finally, if the URL has a hash, move the slider in to position,
// setting the duration to 1 because I don't want it to scroll in the
// very first page load. We don't always need this, but it ensures
// the positioning is absolutely spot on when the pages loads.
scrollOptions.duration = 1;
$.localScroll.hash(scrollOptions);
});
CSS
#slider {
margin-left: 35px;
position: relative;
width: 875px;
}
.scroll {
position: relative;
width: 875px;
height: 268px;
overflow: auto; /* fix for IE to respect overflow */
background: #FFFFFF scroll 0;
}
.scrollContainer div.panel {
position: relative;
height: 210px;
width: 875px; /* change to 560px if not using JS to remove rh.scroll */
}
.scrollButtons {
position: absolute;
top: 115px;
cursor: pointer;
}
.scrollButtons.left {
left: -20px;
}
.scrollButtons.right {
right: -20px;
}