How do I change image A when hovering over image B without JavaScript only CSS

Question

I would like to know how to update image A when I hover over image B using only CSS, is it possible? if not how will I do that using only pure JavaScript (no library). But c

Answer 1

Simple. Let´s suppose you have a div like this:

<div class="myImage">

So, in CSS you set the normal background image, and then you use the :hover pseudo-element to change it to your desired rollover image. Something like:

.myImage{ background-image: url(imageA.jpg);} /*Set the normal image*/
.myImage:hover{ background-image: url(imageB.jpg);} /*Set the rollover image*/

Answer 2

This depends entirely on your mark-up, as I pointed out in the comments. In the absence of seeing any mark-up to work with, I can only post some general suggestions; however it's important to note that the element you want to affect (F) must appear later in the DOM (be a child of the element F, or be subsequent sibling, or descendant of a subsequent sibling) than the element E with which you want to interact.

That said, the following approaches will work, with the associated mark-up:

Sibling-based selection:

Hovering over the first img inside of #a toggles the display of the subsequent img elements, using the E ~ F (general sibling) combinator:

<div id="a">
    <img src="http://www.lorempixel.com/200/400/nature" />
    <img class="first" src="http://www.lorempixel.com/200/400/people" />
    <img class="second" src="http://www.lorempixel.com/200/400/sports" />    
</div>​​​​​

#a img.second,
#a img.first:hover ~ img.second {
    display: none;
}

#a img:hover ~ img.first {
    display: none;
}

#a img:hover ~ img.second {
    display: inline-block;
}​

JS Fiddle demo.

Hovering over #a changes switches the display of the .first and .second images inside of #b, using the E + F (immediate sibling) combinator:

<div id="a">
    <img src="http://www.lorempixel.com​​​​​​​​​​​​​​​​​​​​​​​​/200/400/nature" />
</div>
<div id="b">
    <img class="first" src="http://www.lorempixel.com/200/400/people" />
    <img class="second" src="http://www.lorempixel.com/200/400/sports" />    
</div>​​​​​​​​​​​​​​​​​

#a,#b {
    float: left;
    border: 1px solid #000;
    padding: 0.2em;
}

img.second {
    display: none;
}

#a:hover + #b img.first {
    display: none;
}
#a:hover + #b img.second {
    display: inline-block;
}​

JS Fiddle demo.

Descendant-based selection:

Using the E F general descendant combinator (I'm not actually entirely sure a space character is a combinator, but regardless...it's based on F being a descendant of E):

<div id="a">
    <img class="first" src="http://www.lorempixel.com/200/400/people" />
    <img class="second" src="http://www.lorempixel.com/200/400/sports" />    
</div>​

#a img.second {
    display: none;
}

#a:hover img.first {
    display: none;
}

#a:hover img.second {
    display: inline-block;
}

JS Fiddle demo.

Using E > F the immediate-child/immediate-descendant combinator:

<div id="a">
    <img class="first" src="http://www.lorempixel.com/200/400/people" />
    <div>
        <img class="second" src="http://www.lorempixel.com/200/400/sports" />
    </div>
</div>​    div {
    display: inline-block;
}

img {
    display: none;
    border: 1px solid #000;
    padding: 0.2em;
}

#a > img {
    display: inline-block;
}

#a:hover img {
    display: inline-block;
}​

JS Fiddle demo.

---

There's also the chance to use pseudo-elements and css-generated content (in compliant/up-to-date browsers):

<div id="a"></div>​

#a {
    width: 200px;
    height: 400px;
    background-image: url(http://www.lorempixel.com/200/400/people);
    background-repeat: none;
    background-position: 50% 50%;
    position: relative;
}

​#a:hover::after {
    content: url(http://www.lorempixel.com/200/400/animals);
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 100%;
}​

JS Fiddle demo.

Answer 3

In your particular case it's easy, since #bg is a child of #hv

Just change your hover selector from what you have to this:

#bg:hover #hv {...}

See my fork of your fiddle here: http://jsfiddle.net/xJSQt/

Answer 4

To update the background position on the inner element #hv when hovering the outer element #bg, you can:

See this Working Fiddle Example!

#bg:hover #hv {
   ...
}