Develop Reference

Css / JS hide element on collision

I have an image that I am using at the bottom of my clients page. It is an absolute positioned image on the bottom left of the screen, inside the footer div.
.footer__endrow > .chefBottom {
left: 0;
position: absolute;
bottom: 0;
}
This works and looks fine when on the desktop at a normal resolution. However, when the window is made smaller, it starts to collide with the social icons there and goes behind them.
The viewport it self is still well within range of a normal desktop website when viewing the second image so I can't just hide it when its at tablet or mobile size as the collision would have already hapend.
Is there a way with javascript or css to hide an image when it collides with another element? For example detect if the element touches another one and then hide it?

Just find your breakpoint of when images collide with social icons using chrome developer tool inspect element in responsive mode and then use media query to hide the element at the end of your css file like
#media screen and (max-width:480px){
.footer__endrow > .chefBottom{
display:none;
}
}
Note: Here I have used 480px as a breakpoint

If you want to make it with javascript way, then it is better to solve this way.
$(window).on("resize", function(){
var $imgDiv; // assign image div here
var $socialIconsDiv; // assign social icon div here
var $imgDivRightOffset = $($imgDiv).offset().left + $("$imgDiv").outerWidth(); //get image right position
var $socialIconDivLeftOffset = $($socialIconsDiv).offset().left // get social icons left position
if( $socialIconDivLeftOffset <= (imgDivRightOffset) ){
$($socialIconDivLeftOffset).hide();// Hide social icons here
}
});

Hi You can check the position of both the image and see if the position is overlapping if it is over lapping in the if condition you can hide it.
window.addEventListener('resize', function () {
var imageOne = document.getElementById('firstImage');
// check for the image which you want overlapping add the condition as per that.
if (imageTwo.offsetLeft <= imageOne.offsetLeft) {
//use this command to hide the image.
imageOne.style.visibility = 'visible';
}
});

Disable scrolling but keep scrollbar CSS

I can't find a solution to this, there was a question over here, but the answers are not very usable (at least for me).
I have a JavaScript modal pop-up that disables everything on the background by placing transparent div over the page. It also disables the scrolling by setting the overflow to hidden, and must do so, because the page is scrollable with the mouse wheel otherwise and distracts the user.
The problem is, when hiding and showing the scrollbar the page resizes and the effect is ugly. Also, my page is designed in such a way that if I stop it from resizing that would be ugly either.
What I want is to disable the scrollbar, but keep it visible (the page content is longer than the screen fits). Is this somehow possible in CSS?

Instead of changing the css, which will remove the scrollbar, and as you said change the layout of the page, try calling a jquery function instead.
// call your pop up and inside that function add below
$('body').on('scroll mousewheel touchmove', function(e) {
e.preventDefault();
e.stopPropagation();
return false;
});
then when you close the modal, call the same function but replace on with off

Since scrollbars are not all 17px wide, I solved this with JavaScript. That is, I calculated the exact width of the scrollbar and added an equal amount of margin to the right of the body element. This also works when the scrollbar isn't present due to a high resolution or a lack of content.
function toggleMenu() {
// get width before hiding scrollbar
let oldWidth = document.documentElement.clientWidth;
// toggle CSS class that sets overflow to hidden
document.body.classList.toggle('MenuOpen');
// get new width after hiding scrollbar
let newWidth = document.documentElement.clientWidth;
// set margin-right value equal to width of the scrollbar
let scrollbarWidth = Math.max(0, newWidth - oldWidth);
document.body.style.marginRight = `${scrollbarWidth}px`;
}
...and my CSS looks like:
html {
background-color: #e6e6e6; /* color of fake scrollbar */
}
body.MenuOpen {
overflow: hidden;
}

Once you start showing your popup, give the body a class (like popupOpen). This should be an easy workaround.
.popupOpen {
overflow: hidden;
margin-right: 17px //size of the scrollbar in each browser
}
When you close your popup, simply remove the class from the body.

How can I control an image's size

I am a skilled database / application programmer for the PC. I am also an ignorant html / javascript / web programmer.
I am creating some documentation about some .Net assemblies for our intranet. Ideally I would like to display an image full size if the browser window can fit it. If not then I would like to reduce it and toggle between a small version and full size version by a click. It is a dependency chart and can be different sizes for different pages. I would prefer a single function to handle this but being it is for our use none of the requirements I mentioned is set in stone. I would like to make it work well but nothing is mandatory.
I read a lot of stuff but couldn't find anything that matched what I wanted. First I tried this (after a few iterations):
<img src='Dependancy Charts/RotairAORFQ.png' width='100%' onclick='this.src="Dependancy Charts/RotairAORFQ.png";this.width=this.naturalWidth;this.height=this.naturalHeight;' ondblclick='this.src="Dependancy Charts/RotairAORFQ.png";this.width="100%";'>
It has problems. First off it enlarges a small image and it looks funny. Second I would have to put the code in every page. Third it requires a double click to restore it. I was going to live with those short commings but the double click fails. I can't figure out how to restore it.
So I tried to get fancy. I couldn't figure out how to get past problem 1, but solved 2 and 3 by creating a function in a separate file. Then I ran into what appeared to be the same problem. This was my second attempt:
function ImageToggle(Image)
{
if (ImageToggle.FullSize == 'undefined')
ImageToggle.FullSize = false;
if (ImageToggle.FullSize)
{
Image.width='100%';
ImageToggle.FullSize = false;
}
else
{
Image.width=Image.naturalWidth;
ImageToggle.FullSize = true;
}
return 0
}
And in my page:
<img src='Dependancy Charts/RotairAORFQ.png' width='100%' onclick='ImageToggle(this)'>
Can what I want be done? It doesn't sound impossible. If it is a large amount of effort would be required then alternate suggestions are acceptable.

You're probably interested in the max-width: 100% CSS property, rather than a flat-out width:100%. If you have a tiny image, it'll stay tiny. If you have a huge image, it gets resized to the width of the containing element.
For example: http://jsbin.com/kabepo/1/edit uses a small and a huge image, both with max-width:100%. As you can see, the small image is untouched, the huge image is resized to something sensible.

I would recommend that you set a the max-width: 100% CSS property for the image.
This will prevent the image's width from expanding to be greater than the container's width.
You can also do the same with max-height: 100% if you are having problems with the image overflowing vertically.
Please see this JSFiddle for an example.
(Note: If you set both a width and a height attribute on the <img> tag directly or in your CSS file your image will not be scaled proportionally.)

Does it have to be a toggle or would a mouseover work for you as well?
<style>
.FullSize { width:100px; height:auto; }
.FullSize:hover { width:90%; height:auto; }
</style>
<img src="Dependancy Charts/RotairAORFQ.png" class="FullSize">
Note: when image is made larger IN the page - the surrounding content will be displaced around it - depending on how you have set up the layout.
Also if you have any body margins or table or div paddings, using image width at 100% will make the page scroll. To check just change 90% to 100% and work your way up / down.
You could also force the image to be a specific size until the browser gets made smaller by the user / has a smaller resolution.
<style>
.FullSize {width:1000px;max-width:100%;height:auto;}
</style>
<img src="Dependancy Charts/RotairAORFQ.png" class="FullSize">
A tip: the image used must be the largest one. So minimum width of lets say 1200 pixels wide (if that is the forced image size you use). That way regardless of size it is it will remain clearer than a small image becoming a large. Since it's an intranet, file size shouldn't be an issue.

Thanks all for your help. Rob and Mike both pointed me to an excellent solution. I now have my page load with an image that fits the browser window, resizes with the browser and if the user is interested they can expand the image and scrollbars appear if necessary. I got this to work in a function so minimal code is needed for each page.
To load the image:
<p style="overflow:auto;">
<img src='Dependancy Charts/RotairAORFQ.png' width="100%" onclick='ImageToggle(this)'>
</p>
And the function:
function ImageToggle(Image)
{
if (ImageToggle.FullSize == 'undefined')
ImageToggle.FullSize = false;
if (ImageToggle.FullSize)
{
Image.style="max-width: 100%";
ImageToggle.FullSize = false;
}
else
{
Image.style="max-width: none";
Image.width=Image.naturalWidth;
ImageToggle.FullSize = true;
}
return 1
}

if you want to get current browser window size and if you want to do it on a click event so try this in jquery or javascript:
<script>
$("#myButton").click(function(){
var x = window.innerHeight; // put current window size in x (ie. 400)
});
</script>

Using Jquery to toggle on and off items based distance to top

I am creating a site in which there are a number of fixed background images that you scroll past. Associated with each fixed background is an image slider (or text) that is hidden until the title is clicked on. These items are all fixed positioned.
I was able to make this work by using z-index to place items in order top to bottom/first to last and then have each disappear in turn using:
$(document).scroll(function() {
$('#porttitle').toggle($(this).scrollTop() < 225);
});
However, I am unable to use this because the length pixel distance down on the page changes based on the screen size. I am pretty new to Jquery but wanted to try to use .offset .top to have the item disappear not based on the pixel length to the top of the page but instead when an element appears on the screen. This is what I have so far but it isn't seeming to work.
$(document).scroll(function() {
$('#porttitle').toggle($(this).scrollTop() < $(‘article.post-100’).offset().top);
});
Here is the link to the site: http://s416809079.onlinehome.us (not final location - just developing)
Any thoughts?
Thanks!

I think this may work for you, read the comments on the code for a line by line explanation.
Working Example
$(window).scroll(function () { // When the user scrolls
$('div').each(function () { // check each div
if ($(window).scrollTop() < $(this).offset().top) { // if the window has been scrolled beyond the top of the div
$(this).css('opacity', '1'); //change the opacity to 1
} else { // if not
$(this).css('opacity', '0'); // change the opacity to 0
}
});
});
I'm conditionally changing the opacity rather than using toggle because:
...jQuery does not support getting the offset coordinates of hidden
elements or accounting for borders, margins, or padding set on the
body element.
While it is possible to get the coordinates of elements with
visibility:hidden set, display:none is excluded from the rendering
tree and thus has a position that is undefined.
Related documentation:
.offset()
.each()
.scroll()
.scrollTop()

Fixed sidebar too tall for browser (bottom is getting cut off)

Let's say I have a fixed sidebar that is XXpx tall (Refer to http://www.getskeleton.com/ if you want a visual of what I mean). The sidebar looks exactly the way I want, as long as the height of the browser is bigger than the sidebar. However, when the browser height shrinks below the height of the sidebar, the bottom contents get cut off.
Initially, the sidebar has position: fixed, but if the browser gets too small to contain the entire sidebar, I want to change it to position: aboslute. Essentially, I'd like to make it so on both page load and any time the user resizes finishes resizing the page it will check to make sure that the bottom content isn't being cut off, then assign the appropriate position attribute.

You could use a vertical media query for this, like so (let's say the sidebar is 700px tall.)
#sidebar {
position: absolute;
}
media screen and (min-height:700px) {
#sidebar { position: fixed; }
}
By declaring the absolute position first, you make sure that browsers that don't support media queries will get the absolutely positioned sidebar, which will still be functional.

Do something like this:
var $sidebar = $('#idOfSidebar')
,$w = $(window);
$w.resize(function () {
var pos = $w.height() < $sidebar.height()? 'absolute': 'fixed';
$sidebar.css({position: pos});
});

An option is to use overflow: auto for fixed blocks that can be potentially taller than browser`s client height. This can be used as default pure-CSS solution that can work in conjunction with JavaScript methods.