Acquire IMG-element width before it is rendered - javascript

I wrote this script so that the wallpaper (picture of an object) on my site is positioned right and centred correctly when the window is resized. Now it works just the way I want, but only when the window resizes, under normal conditions when the window hasn't been resized it apparently can't get the width of the img element cause it doesn't subtract the half of it for the left css property. How do I get it?
HTML:
<div class="wallpaper" id="wallpaper">
<img src=#bgImage.img id="wallpaperImg" style="height:100%; width: auto; position: fixed;">
</div>
JS:
<script type="text/javascript">
var screenWidth;
var screenHight;
var totalHeight;
var aspectRatio;
var blah = false; //Ugly hack
var navbarSize = 41;
var wallpaper = $("#wallpaperImg");
function getAspectRatio(h,w){
return (h-1)/w; //Ugly hack
}
function resizeWallpaper(w,h){
if(typeof(aspectRatio)==='undefined') aspectRatio = #bgImage.aspectRatio; //delivered by server framework
totalHeight = (h-navbarSize).toString() + 'px';
wallpaper.css("height",totalHeight);
wallpaper.css("width","auto");
wallpaper.css("left",(w/2)-(wallpaper.width()/2)+'px');
wallpaper.css("top",'41px');
if(getAspectRatio(wallpaper.height(),wallpaper.width()) > aspectRatio && blah){
wallpaper.css("width",(w).toString() + 'px')
wallpaper.css("height","auto")
wallpaper.css("top",((h/2)-(wallpaper.height()/2))+20.5+'px');
wallpaper.css("left",'0px');
}
}
resizeWallpaper($(window).width(),$(window).height());
blah = true;
$(window).resize(function() {
resizeWallpaper($(window).width(),$(window).height());
});
</script>
Quick upload of what I'm talking about: Site

You have to wait for the image to download before you can resize it. Surround the initial call in a load handler:
wallpaper.on('load', function() {
resizeWallpaper($(window).width(),$(window).height());
});

Related

Dynamically setting DIV height in relation to another DIV

I'm trying to set a div's height in relation to another div. 'gridimg' has an image in it and 'gridtext' has text so when the page is resized, the div containing the text changes height. I have the following code in a .js file:
window.onresize = function resize() {
var right = document.getElementById('gridimg').style.height;
var left = document.getElementById('gridtext').style.height;
document.getElementById('gridimg').style.height=left;
});
I'm trying to get it to call this function when the window is resized so the divs stay the same size but it's not working. I'm new to external javascript so could anyone help me :)
If you want to read an element height, you have to use the offsetHeight property. The style.height is for setting the height.
http://codepen.io/bajzarpa/pen/oZVOrL
I would write a function to check for resize and get the #gridimg height like this answer: Call a function when window is resized
Then watch for it like this:
$(window).resize(function () {
yourMethod( $('#gritext'));
});
Similar: https://stackoverflow.com/a/15205712/6254070
Here's a code snippet showing how to do that, based loosely on the W3 Tryit:
<!DOCTYPE html>
<html>
<body onresize="myFunction()">
<style>
#thetext {
width: 100%;
height: 50px;
display: block;
clear: both;
overflow: hidden;
}
#otherdiv {
background-color: green;
display: block;
clear: both;
overflow: hidden;
}
</style>
<p>Try to resize the browser window to display the windows height and width.</p>
<p id="demo"></p>
<div id="thetext"><strong>Note:</strong> this example will not work properly in IE8 and earlier. IE8 and earlier do not support the outerWidth/outerHeight propery of the window object.</div>
<div id="otherdiv"></div>
<script>
function myFunction() {
setTimeout(function() {
var sourceEl = document.getElementById('thetext');
var targetEl = document.getElementById('otherdiv');
var newHeight = sourceEl.offsetHeight;
// || sourceEl.getBoundingClientRect().height;
targetEl.width = sourceEl.offsetWidth;
targetEl.style.height = newHeight + 'px';
var w = targetEl.offsetWidth;
var h = targetEl.offsetHeight;
var txt = "Target size: width=" + w + ", height=" + h;
document.getElementById('demo').innerHTML = txt;
}, 0);
}
</script>
</body>
</html>

Set body width,same as clients window

What i'm looking for,is a way to set the width of the body same as the clients window's,using JAVA.
This code i've borrowed from W3S,but its not working in my case -
function body_width(w)
{
var w = window.innerWidth
|| document.documentElement.clientWidth
|| document.body.clientWidth;
var x = document.body;
x.style.width = w;
}
window.onload = body_width(w);
Also i've gave "style="width:;" " to the body
Have you tried using screen.availWidth and screen.availHeight?
The screen.availHeight property returns the height of the visitor's screen, in pixels, minus interface features like the Windows Taskbar.
The screen.availWidth property returns the width of the visitor's screen, in pixels, minus interface features like the Windows Taskbar.
It could be done easily with Viewport-Percentage Lengths:
The viewport-percentage lengths are relative to the size of the initial containing block. When the height or width of the initial containing block is changed, they are scaled accordingly.
HTML
<div>Your Container</div>
And CSS
div {
height:100vh;
}
That is all you need.
Here is JSFiddle example.
Try to set width in % :
<style>
Body{
width:100%;
}
</style>
not window.onload = body_width(w);
its window.onload = body_width;
This option worked out perfectly.
<script>
function body_width(w)
{
var w = screen.availWidth
var x = document.body;
x.style.width = screen.availWidth + "px";
}
window.onload = body_width;
</script>
Thanks 2 ivarz_LV
When I tested, using
body {
height: 100%;
}
won't work. Try using this in style:
body {
height: 100vh;
}
I figured using vh would work better.

set iframe height dynamically depending on content [duplicate]

I am loading an aspx web page in an iframe. The content in the Iframe can be of more height than the iframe's height. The iframe should not have scroll bars.
I have a wrapper div tag inside the iframe which basically is all the content. I wrote some jQuery to make the resize happen :
$("#TB_window", window.parent.document).height($("body").height() + 50);
where
TB_window is the div in which the Iframe is contained.
body - the body tag of the aspx in the iframe.
This script is attached to the iframe content. I am getting the TB_window element from the parent page. While this works fine on Chrome, but the TB_window collapses in Firefox. I am really confused/lost on why that happens.
You can retrieve the height of the IFRAME's content by using:
contentWindow.document.body.scrollHeight
After the IFRAME is loaded, you can then change the height by doing the following:
<script type="text/javascript">
function iframeLoaded() {
var iFrameID = document.getElementById('idIframe');
if(iFrameID) {
// here you can make the height, I delete it first, then I make it again
iFrameID.height = "";
iFrameID.height = iFrameID.contentWindow.document.body.scrollHeight + "px";
}
}
</script>
Then, on the IFRAME tag, you hook up the handler like this:
<iframe id="idIframe" onload="iframeLoaded()" ...
I had a situation a while ago where I additionally needed to call iframeLoaded from the IFRAME itself after a form-submission occurred within. You can accomplish that by doing the following within the IFRAME's content scripts:
parent.iframeLoaded();
A slightly improved answer to Aristos...
<script type="text/javascript">
function resizeIframe(iframe) {
iframe.height = iframe.contentWindow.document.body.scrollHeight + "px";
}
</script>
Then declare in your iframe as follows:
<iframe onload="resizeIframe(this)" ...
There are two minor improvements:
You don't need to get the element via document.getElementById - as you already have it in the onload callback.
There's no need to set the iframe.height = "" if you're going to reassign it in the very next statement. Doing so actually incurs an overhead as you're dealing with a DOM element.
Edit:
If the content in the frame is always changing then call:
parent.resizeIframe(this.frameElement);
from within the iframe after the update. Works for same origin.
Or to auto detect:
// on resize
this.container = this.frameElement.contentWindow.document.body;
this.watch = () => {
cancelAnimationFrame(this.watcher);
if (this.lastScrollHeight !== container.scrollHeight) {
parent.resizeIframeToContentSize(this.frameElement);
}
this.lastScrollHeight = container.scrollHeight;
this.watcher = requestAnimationFrame(this.watch);
};
this.watcher = window.requestAnimationFrame(this.watch);
I found that the accepted answer didn't suffice, since X-FRAME-OPTIONS: Allow-From isn't supported in safari or chrome. Went with a different approach instead, found in a presentation given by Ben Vinegar from Disqus. The idea is to add an event listener to the parent window, and then inside the iframe, use window.postMessage to send an event to the parent telling it to do something (resize the iframe).
So in the parent document, add an event listener:
window.addEventListener('message', function(e) {
var $iframe = jQuery("#myIframe");
var eventName = e.data[0];
var data = e.data[1];
switch(eventName) {
case 'setHeight':
$iframe.height(data);
break;
}
}, false);
And inside the iframe, write a function to post the message:
function resize() {
var height = document.getElementsByTagName("html")[0].scrollHeight;
window.parent.postMessage(["setHeight", height], "*");
}
Finally, inside the iframe, add an onLoad to the body tag to fire the resize function:
<body onLoad="resize();">
Add this to the iframe, this worked for me:
onload="this.height=this.contentWindow.document.body.scrollHeight;"
And if you use jQuery try this code:
onload="$(this).height($(this.contentWindow.document.body).find(\'div\').first().height());"
you could also add a repeating requestAnimationFrame to your resizeIframe (e.g. from #BlueFish's answer) which would always be called before the browser paints the layout and you could update the height of the iframe when its content have changed their heights. e.g. input forms, lazy loaded content etc.
<script type="text/javascript">
function resizeIframe(iframe) {
iframe.height = iframe.contentWindow.document.body.scrollHeight + "px";
window.requestAnimationFrame(() => resizeIframe(iframe));
}
</script>
<iframe onload="resizeIframe(this)" ...
your callback should be fast enough to have no big impact on your overall performance
There are four different properties you can look at to get the height of the content in an iFrame.
document.documentElement.scrollHeight
document.documentElement.offsetHeight
document.body.scrollHeight
document.body.offsetHeight
Sadly they can all give different answers and these are inconsistant between browsers. If you set the body margin to 0 then the document.body.offsetHeight gives the best answer. To get the correct value try this function; which is taken from the iframe-resizer library that also looks after keeping the iFrame the correct size when the content changes,or the browser is resized.
function getIFrameHeight(){
function getComputedBodyStyle(prop) {
function getPixelValue(value) {
var PIXEL = /^\d+(px)?$/i;
if (PIXEL.test(value)) {
return parseInt(value,base);
}
var
style = el.style.left,
runtimeStyle = el.runtimeStyle.left;
el.runtimeStyle.left = el.currentStyle.left;
el.style.left = value || 0;
value = el.style.pixelLeft;
el.style.left = style;
el.runtimeStyle.left = runtimeStyle;
return value;
}
var
el = document.body,
retVal = 0;
if (document.defaultView && document.defaultView.getComputedStyle) {
retVal = document.defaultView.getComputedStyle(el, null)[prop];
} else {//IE8 & below
retVal = getPixelValue(el.currentStyle[prop]);
}
return parseInt(retVal,10);
}
return document.body.offsetHeight +
getComputedBodyStyle('marginTop') +
getComputedBodyStyle('marginBottom');
}
Other answers were not working for me so i did some changes. Hope this will help
$('#iframe').on("load", function() {
var iframe = $(window.top.document).find("#iframe");
iframe.height(iframe[0].ownerDocument.body.scrollHeight+'px' );
});
Just in case this helps anyone. I was pulling my hair out trying to get this to work, then I noticed that the iframe had a class entry with height:100%. When I removed this, everything worked as expected. So, please check for any css conflicts.
I am using jQuery and the code below working for me,
var iframe = $(window.top.document).find("#iframe_id_here");
iframe.height(iframe.contents().height()+'px' );
You can refer related question here - How to make width and height of iframe same as its parent div?
To set dynamic height -
We need to communicate with cross domain iFrames and parent
Then we can send scroll height/content height of iframe to parent window
And codes - https://gist.github.com/mohandere/a2e67971858ee2c3999d62e3843889a8
Rather than using javscript/jquery the easiest way I found is:
<iframe style="min-height:98vh" src="http://yourdomain.com" width="100%"></iframe>
Here 1vh = 1% of Browser window height. So the theoretical value of height to be set is 100vh but practically 98vh did the magic.
All other answers are correct but what if the iframe has some dynamic content like a map that loads later and dynamically changes your iframe scroll height. This is how I achieved it.
var iFrameID = document.getElementById('idIframe');
intval = setInterval(function(){
if(iFrameID.scrollHeight == iFrameID.contentWindow.document.body.scrollHeight){
clearInterval(intval);
}else{
iFrameID.height = iFrameID.contentWindow.document.body.scrollHeight + "px";
}
},500)
I simply wrap the code inside setInterval which matches the iframe scroll height with iframe content scroll height then clear the interval.
in my project there is one requirement that we have make dynamic screen like Alignment of Dashboard while loading, it should display on an entire page and should get adjust dynamically, if user is maximizing or resizing the browser’s window.
For this I have created url and used iframe to open one of the dynamic report which is written in cognos BI.In jsp we have to embed BI report. I have used iframe to embed this report in jsp. following code is working in my case.
<iframe src= ${cognosUrl} onload="this.style.height=(this.contentDocument.body.scrollHeight+30) +'px';" scrolling="no" style="width: 100%; min-height: 900px; border: none; overflow: hidden; height: 30px;"></iframe>
I found the answer from Troy didn't work. This is the same code reworked for ajax:
$.ajax({
url: 'data.php',
dataType: 'json',
success: function(data)
{
// Put the data onto the page
// Resize the iframe
var iframe = $(window.top.document).find("#iframe");
iframe.height( iframe[0].contentDocument.body.scrollHeight+'px' );
}
});
To add to the chunk of window that seems to cut off at the bottom, especially when you don't have scrolling I used:
function resizeIframe(iframe) {
var addHeight = 20; //or whatever size is being cut off
iframe.height = iframe.contentWindow.document.body.scrollHeight + addHeight + "px";
}
This one is useful when you require a solution with no jquery. In that case you should try adding a container and set a padding to it in percentages
HTML example code:
<div class="iframecontainer">
<iframe scrolling="no" src="..." class="iframeclass"width="999px" height="618px"></iframe>
</div>
CSS example code:
.iframeclass{
position: absolute;
top: 0;
width: 100%;
}
.iframecontainer{
position: relative;
width: 100%;
height: auto;
padding-top: 61%;
}
The simple solution is to measure the width and height of the content area, and then use those measurements to calculate the bottom padding percentage.
In this case, the measurements are 1680 x 720 px, so the padding on the bottom is 720 / 1680 = 0.43 * 100, which comes out to 43%.
.canvas-container {
position: relative;
padding-bottom: 43%; // (720 ÷ 1680 = 0.4286 = 43%)
height: 0;
overflow: hidden;
}
.canvas-container iframe {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
}
A slightly improved answer to BlueFish...
function resizeIframe(iframe) {
var padding = 50;
if (iframe.contentWindow.document.body.scrollHeight < (window.innerHeight - padding))
iframe.height = iframe.contentWindow.document.body.scrollHeight + "px";
else
iframe.height = (window.innerHeight - padding) + "px";
}
This takes in consideration the height of the windows screen(browser, phone) which is good for responsive design and iframes that have huge height.
Padding represents the padding you want above and below the iframe in the case it goes trough whole screen.
jQuery('.home_vidio_img1 img').click(function(){
video = '<iframe src="'+ jQuery(this).attr('data-video') +'"></iframe>';
jQuery(this).replaceWith(video);
});
jQuery('.home_vidio_img2 img').click(function(){
video = <iframe src="'+ jQuery(this).attr('data-video') +'"></iframe>;
jQuery('.home_vidio_img1 img').replaceWith(video);
jQuery('.home_vidio_img1 iframe').replaceWith(video);
});
jQuery('.home_vidio_img3 img').click(function(){
video = '<iframe src="'+ jQuery(this).attr('data-video') +'"></iframe>';
jQuery('.home_vidio_img1 img').replaceWith(video);
jQuery('.home_vidio_img1 iframe').replaceWith(video);
});
jQuery('.home_vidio_img4 img').click(function(){
video = '<iframe src="'+ jQuery(this).attr('data-video') +'"></iframe>';
jQuery('.home_vidio_img1 img').replaceWith(video);
jQuery('.home_vidio_img1 iframe').replaceWith(video);
});
Sample using PHP htmlspecialchars() + check if height exists and is > 0:
$my_html_markup = ''; // Insert here HTML markup with CSS, JS... '<html><head></head><body>...</body></html>'
$iframe = '<iframe onload="if(this.contentWindow.document.body.scrollHeight) {this.height = this.contentWindow.document.body.scrollHeight;}" width="100%" src="javascript: \''. htmlspecialchars($my_html_markup) . '\'"></iframe>';
Script
<script type="text/javascript" language="javascript">
$(document).ready(function(){
var height = $(window).height();
$('.myIframe').css('height', height - 200);
});
</script>
iframe
<iframe class="myIframe" width="100%"></iframe>
It's working in my case.
$(document).height() // - $('body').offset().top
and / or
$(window).height()
See Stack Overflow question How to get the height of a body element.
Try this to find the height of the body in jQuery:
if $("body").height()
It doesn't have a value if Firebug. Perhaps that's the problem.
just make iframe container position:absolute and iframe will automatically change its height according to its content
<style>
.iframe-container {
display: block;
position: absolute;
/*change position as you need*/
bottom: 0;
left: 0;
right: 0;
top: 0;
}
iframe {
margin: 0;
padding: 0;
border: 0;
width: 100%;
background-color: #fff;
}
</style>
<div class="iframe-container">
<iframe src="http://iframesourcepage"></iframe>
</div>

Dynamically resize iframe

Situation:
I'm working on a responsive design that involves the typical HTML/CSS combo. Everything is working nicely except in one case where there is an iframe inside of a div. The iframe should adjust automatically to the size of the parent div. A purely css solution has not presented itself so I'm going with a JQuery approach. It works nicely except in one scenario, when resizing from a smaller width to a larger width screen.
HTML:
<div class="container">
<iframe class="iframe-class" src="http://www.cnn.com/"></iframe>
</div>
CSS:
.container {
width: 100%;
height: 250px;
}
.iframe-class {
width: 100%;
height: 100%;
border: 1px solid red;
overflow: auto;
}
Javascript:
$(function () {
setIFrameSize();
$(window).resize(function () {
setIFrameSize();
});
});
function setIFrameSize() {
var ogWidth = 700;
var ogHeight = 600;
var ogRatio = ogWidth / ogHeight;
var windowWidth = $(window).width();
if (windowWidth < 480) {
var parentDivWidth = $(".iframe-class").parent().width();
var newHeight = (parentDivWidth / ogRatio);
$(".iframe-class").addClass("iframe-class-resize");
$(".iframe-class-resize").css("width", parentDivWidth);
$(".iframe-class-resize").css("height", newHeight);
} else {
// $(".iframe-class-resize").removeAttr("width");
// $(".iframe-class-resize").removeAttr("height");
$(".iframe-class").removeClass("iframe-class-resize");
}
}
http://jsfiddle.net/TBJ83/
Problem:
As the window is resized smaller, it continually checks the window width and once it hits < 480 px, the code adds a class called iframe-class-resize and sets the width and height to that class. As the window is resized larger, it removes the class once the size hits 480 px. The problem is that setting the width and height attributes adds them directly to the element and not the class itself. Therefore, removing the class does not remove the new width and heights. I tried to force removing the attributes using removeAttr() (commented out above) but that didn't work.
Anyone see where the code above went wrong? Or any suggestions on how to accomplish having a responsive iframe more effectively? The main things that are required are that the iframe has to be inside the <div></div> and the div may not necessarily have a width or height defined. Ideally, the parent div should have the width and height explicitly defined but the way this site is currently setup, that won't always be possible.
Additional:
In case the above wasn't clear enough, try the following to reproduce the issue:
Open up a browser on a desktop machine. I'm using Chrome on a Windows machine. Don't maximize the browser.
Open up the jsfiddle above (http://jsfiddle.net/TBJ83/). You'll notice that the iframe content spans the entire width of the Preview panel.
Manually resize the width down until the entire window is < 480px. At this point, the iframe content will be pretty tiny.
Manually resize the width back up until the entire window is >> 480px. The goal is to have that iframe content to regain the entire width of the Preview panel. Instead, the content is retaining the resized width and height since the .css() function applies css changes directly to elements rather than to the classes.
Thanks in advance!
You can do this in about 30 characters. Change:
$(".iframe-class").removeClass("iframe-class-resize")
to:
$(".iframe-class").removeClass("iframe-class-resize").css({ width : '', height : '' })
This will reset the width/height you applied to the element. When you use .css() you add whatever you pass-in to the style attribute of the element. When you pass a blank value, jQuery removes that property from the style attribute of the element.
Here is an updated fiddle: http://jsfiddle.net/TBJ83/3/
EDIT
OK, here's something tweaked for performance (and just some other ways to do things):
$(function () {
//setup these vars only once since they are static
var $myIFRAME = $(".iframe-class"),//unless this collection of elements changes over time, you only need to select them once
ogWidth = 700,
ogHeight = 600,
ogRatio = ogWidth / ogHeight,
windowWidth = 0,//store windowWidth here, this is just a different way to store this data
resizeTimer = null;
function setIFrameSize() {
if (windowWidth < 480) {
var parentDivWidth = $myIFRAME.parent().width(),//be aware this will still only get the height of the first element in this set of elements, you'll have to loop over them if you want to support more than one iframe on a page
newHeight = (parentDivWidth / ogRatio);
$myIFRAME.addClass("iframe-class-resize").css({ height : newHeight, width : parentDivWidth });
} else {
$myIFRAME.removeClass("iframe-class-resize").css({ width : '', height : '' });
}
}
$(window).resize(function () {
//only run this once per resize event, if a user drags the window to a different size, this will wait until they finish, then run the resize function
//this way you don't blow up someone's browser with your resize function running hundreds of times a second
clearTimeout(resizeTimer);
resizeTimer = setTimeout(function () {
//make sure to update windowWidth before calling resize function
windowWidth = $(window).width();
setIFrameSize();
}, 75);
}).trigger("click");//run this once initially, just a different way to initialize
});
This can be done using pure CSS as below:
iframe {
height: 300px;
width: 300px;
resize: both;
overflow: auto;
}
Set the height and width to the minimum size you want, it only seems to grow, not shrink.
This is how I would do it, code is much shorter: http://jsfiddle.net/TBJ83/2/
<div class="container">
<iframe id="myframe" src="http://www.cnn.com/"></iframe>
</div>
<script>
$(function () {
setIFrameSize();
$(window).resize(function () {
setIFrameSize();
});
});
function setIFrameSize() {
var parentDivWidth = $("#myframe").parent().width();
var parentDivHeight = $("#myframe").parent().height();
$("#myframe")[0].setAttribute("width", parentDivWidth);
$("#myframe")[0].setAttribute("height", parentDivHeight);
}
</script>
I did it that way for read-ability, but you could make it even shorter and faster...
function setIFrameSize() {
f = $("#myframe");
f[0].setAttribute("width", f.parent().width());
f[0].setAttribute("height", f.parent().height());
}
One selector, so you only look through the DOM once instead of multiple times.
For those using Prestashop, this is how I used the code.
In the cms.tpl file I added the below code:
{if $cms->id==2}
<script type='text/javascript' src='http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js?ver=1.3.2'></script>
<script type="text/javascript" src='../themes/myheme/js/formj.js'></script>
<div style="width: 100%; height: 800px;">
<iframe style=" width: 100%; height: 100%; border: overflow: auto;" src="https://cnn.com"></iframe>
</div>
{/if}
Then created a new js file: formj.js and added the below code:
$(function () {
//setup these vars only once since they are static
var $myIFRAME = $(".iframe-class"),//unless this collection of elements changes over time, you only need to select them once
ogWidth = 970,
ogHeight = 800,
ogRatio = ogWidth / ogHeight,
windowWidth = 0,//store windowWidth here, this is just a different way to store this data
resizeTimer = null;
function setIFrameSize() {
if (windowWidth < 480) {
var parentDivWidth = $myIFRAME.parent().width(),//be aware this will still only get the height of the first element in this set of elements, you'll have to loop over them if you want to support more than one iframe on a page
newHeight = (parentDivWidth / ogRatio);
$myIFRAME.addClass("iframe-class-resize").css({ height : newHeight, width : parentDivWidth });
} else {
$myIFRAME.removeClass("iframe-class-resize").css({ width : '', height : '' });
}
}
$(window).resize(function () {
//only run this once per resize event, if a user drags the window to a different size, this will wait until they finish, then run the resize function
//this way you don't blow up someone's browser with your resize function running hundreds of times a second
clearTimeout(resizeTimer);
resizeTimer = setTimeout(function () {
//make sure to update windowWidth before calling resize function
windowWidth = $(window).width();
setIFrameSize();
}, 75);
}).trigger("click");//run this once initially, just a different way to initialize
});

force div height to nearest multiple of the background image height

Bit of a tricky situation to explain. Basically the overall image I'm trying to lay under my content div of my website is a messy box with grungy borders that bend in and out.
What I've got so far is something like this (irrelevant code removed)
<div class="content-top"><img src="content-top.png"></div>
<div id="content"> <!-- WORDPRESS LOADS CONTENT HERE --> </div>
<div class="content-bottom"><img src="content-bottom.png"></div>
CSS:
#content {
background: url("assets/images/content-bg.png") repeat-y scroll 0 0 transparent;
}
the content-bg.png image is 300px high and is a repeatable image creating a patterned border either side.
The problem is the content-bottom.png image only looks right when placed at the end of one of these 300px tiles. If the page content is of a height that causes only half of the last background tile to be displayed the lines don't match up.
Typing this I doubt the answer lies in CSS and instead I'll need a javascript/jquery solution but as to the specifics of how to do so I'm unsure.
Here's asolution to your problem. It will expand the content container to the next height that is a multiple of 300.
Plain JavaScript version
var e = document.getElementById('content');
var height = e.clientHeight;
var newHeight = 300 * Math.ceil(height / 300);
e.setAttribute('style', 'height: ' + newHeight + 'px;');
Demo
Try before buy
jQuery version
var e = $('#content');
e.css('height', 300 * Math.ceil(e.height() / 300));
Demo
Try before buy
Here's a i-can't-sleep-solution that supports a dynamic background image:
var content = $('#content'),
height = content.height(),
fixedImageHeight = null, //.. number (pick one)
srcImage = null, //.. url to image (pick one)
imageHeight = function() {
return fixedImageHeight || function() {
var image = new Image();
image.src = srcImage;
return image.height;
}();
}(),
neededPadding = (height > imageHeight)
? height % imageHeight
: imageHeight - height;
content.height(height + neededPadding);

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