How can I animate the opacity of the background of a div?

css, javascript, jquery, jquery-animate, opacity

Solution

First of all you need to set the property correctly

$('#test').animate({ 'background-color': 'rgba(0, 0, 0, 0.7)' },1000);

then you need to include jquery-ui to animate colours.

http://jsfiddle.net/7twXW/11/

You can also use css transitions to animate background colours

#test {
    background-color: rgba(0, 0, 0, 0);
    -webkit-transition:background-color 1s;
    -moz-transition:background-color 1s;
    transition:background-color 1s;
}

http://jsfiddle.net/7twXW/13/

Problem

I have a div #test with a 0 opacity background, I want to animate it until reach the opacity of 0.7. But .animate doesn't seem to work with the css rgba. My css is: ``` #test { background-color: rgba(0, 0, 0, 0); } ``` my html: ``` <div id="test"> <p>Some text</p> <img src="http://davidrhysthomas.co.uk/img/dexter.png" /> </div> ``` and my jQuery: ``` $('#test').animate({ background-color: rgba(0, 0, 0, 0.7) },1000); ``` Here a jsFiddle: http://jsfiddle.net/malamine_kebe/7twXW/10/ thanks a lot for helping!

Original source