Develop Reference

Centering div margin top and margin bottom

I'm trying to get margin-top and margin-bottom to center my <div>. This JavaScript, which I wrote, works. However, if the site is cached once, CTRL+F5 refresh causes the script to receive a wrong clientHeight. Refreshing second time, retrieves the correct clientHeight.
I've tried using window.load and this works. However, it is so slow that the <div> loads and after 2 seconds, it shifts to the middle.
<script type="text/javascript">
var height = $(window).height();
var clientHeight = document.getElementById('account-wall').clientHeight;
var calc_height = (height - clientHeight) / 2;
document.getElementById("account-wall").style.marginTop = calc_height + 'px';
document.getElementById("account-wall").style.marginBottom = calc_height + 'px';
</script>
<script type="text/javascript">
$(window).load(function() {
var height = $(window).height();
console.log(height);
var clientHeight = $('.account-wall').height();
console.log(clientHeight);
var calc_height = (height - clientHeight) / 2;
document.getElementById("account-wall").style.marginTop = calc_height + 'px';
document.getElementById("account-wall").style.marginBottom = calc_height + 'px';
});
</script>

Use a resize event since you need it to be centered even if the window.height changes. To make sure it is centered from the beggining use .resize() to trigger the event.
$(window).on('resize', function(event){
var height = $(window).height();
console.log(height);
var clientHeight = $('.account-wall').height();
console.log(clientHeight);
var calc_height = (height - clientHeight)/2;
document.getElementById("account-wall").style.marginTop = calc_height+'px';
document.getElementById("account-wall").style.marginBottom = calc_height+'px';
}).resize();

calculate and set the height for some div (initial settings). When the height of the browser window is changed --> change the height for div

I need calculate and set the height for some div (initial settings). When the height of the browser window is changed --> change the height for div.
How will be better to rewrite this code (I want do initial settings once and change it when window resize):
$(document).ready(function () {
var height = document.documentElement.clientHeight - 500;
if (height < 135) {
height = 135;
}
document.getElementById('left_space').style.height = height + 'px';
$(window).resize(function () {
var height = document.documentElement.clientHeight - 500;
if (height < 135)
{
height = 135;
}
document.getElementById('left_space').style.height = height + 'px';
});
});

If you are purely looking to tidy up the code, it could look something like this:
$(document).ready(function () {
var resizeIt = function() {
var height = Math.max(document.documentElement.clientHeight - 500, 135);
$('#left_space').css('height', height + 'px');
};
resizeIt();
$(window).resize(function () {
resizeIt();
});
});
Here I have pulled out the lines of code that set the height into their own function, so the code is not duplicated. Then I took advantage of some of the shorter syntax you can use in jQuery for finding and changing styles of elements.

is that what you are looking for?
api.jquery.com
jQuery(document).ready(function () {
$(window).resize(function() {
var height = document.documentElement.clientHeight - 500;
if (height < 135) {
height = 135;
}
document.getElementById('left_space').style.height = height + 'px';
jQuery(window).resize(function () {
var height = document.documentElement.clientHeight - 500;
if (height < 135)
{
height = 135;
}
document.getElementById('left_space').style.height = height + 'px';
});
});
});

I think jQuery(window).resize one would be good

get variable comprehensive to other function

I have the following:
if ($firstBG.hasClass("inview")) {
$(window).resize(function () {
var height = $(window).height();
var getfactor1 = 680 / 697;
var posval1 = height * getfactor1;
console.log(posval1);
});
$firstBG.css({
'backgroundPosition': posval1)
});
}
But it does not get the value of posval1 in the background function. What am I doing wrong? I want to get the value of posval1 in the if inview and on resize function!
Thanks.

You will need to set the css property from the resize handler. If you want to initialize it, you just could trigger it:
if($firstBG.hasClass("inview")){
$(window).resize(function() {
var height = $(window).height();
var getfactor1 = 680/697;
var posval1 = height*getfactor1;
console.log(posval1);
$firstBG.css({'backgroundPosition': posval1)});
}).resize();

Live Detect Browser Size - jQuery / JavaScript

Is there a jQuery plugin or a way using straight JavaScript to detect browser size.
I'd prefer it is the results were 'live', so if the width or height changes, so would the results.

JavaScript
function jsUpdateSize(){
// Get the dimensions of the viewport
var width = window.innerWidth ||
document.documentElement.clientWidth ||
document.body.clientWidth;
var height = window.innerHeight ||
document.documentElement.clientHeight ||
document.body.clientHeight;
document.getElementById('jsWidth').innerHTML = width; // Display the width
document.getElementById('jsHeight').innerHTML = height;// Display the height
};
window.onload = jsUpdateSize; // When the page first loads
window.onresize = jsUpdateSize; // When the browser changes size
jQuery
function jqUpdateSize(){
// Get the dimensions of the viewport
var width = $(window).width();
var height = $(window).height();
$('#jqWidth').html(width); // Display the width
$('#jqHeight').html(height); // Display the height
};
$(document).ready(jqUpdateSize); // When the page first loads
$(window).resize(jqUpdateSize); // When the browser changes size
jsfiddle demo
Edit: Updated the JavaScript code to support IE8 and earlier.

you can use
function onresize (){
var h = $(window).height(), w= $(window).width();
$('#resultboxid').html('height= ' + h + ' width: ' w);
}
$(window).resize(onresize );
onresize ();// first time;
html:
<span id=resultboxid></span>

This should return the visible area:
document.body.offsetWidth
document.body.offsetHeight
I guess this is always equal to the browser size?

use width and height variable anywhere you want... when ever browser size change it will change variable value too..
$(window).resize(function() {
width = $(this).width());
height = $(this).height());
});

Do you mean something like this window.innerHeight; window.innerWidth $(window).height(); $(window).width()

You can try adding even listener on re-size like
window.addEventListener('resize',CheckBrowserSize,false);
function CheckBrowserSize()
{
var ResX= document.body.offsetHeight;
var ResY= document.body.offsetWidth;
}

jQuery - How to know if window is resizing in width/height or both?

I have a little problem with window resizing using jQuery's function .resize(). I would like to know which dimension is getting bigger/smaller - width or height. I need this because if I just put two conditions - if width is for 50px bigger than div and if height is for 50px bigger than div,
// (pseudocode)
if width = div.width + 50px
width = something
if height = div.height + 50px
height = something
then is working on just one condition and I can resize only width or height.
How could I know which dimension is changing in size or if both are?

By saving last window size values in variables.
var h = $(window).height(), w = $(window).width();
$(window).resize(function(){
var nh = $(window).height(), nw = $(window).width();
// compare the corresponding variables.
h = nh; w = nw; // update h and w;
});

Save the previous size and compare with it, everytime the size changes.
For ex:
var prevW = -1, prevH = -1;
$(document).ready(function() {
// ... other stuff you might have inside .ready()
prevW = $(window).width();
prevH = $(window).height();
});
$(window).resize(function() {
var widthChanged = false, heightChanged = false;
if($(window).width() != prevW) {
widthChanged = true;
}
if($(window).height() != prevH) {
heightChanged = true;
}
// your stuff
prevW = $(window).width();
prevH = $(window).height();
});
Demo: http://jsfiddle.net/44aNW/