Description: Adjust the opacity of the matched elements.
durationA string or number determining how long the animation will run.
opacityA number between 0 and 1 denoting the target opacity.
callbackA function to call once the animation is complete.
The .fadeTo()
method animates the opacity of the matched elements.
Durations are given in milliseconds; higher values indicate slower animations, not faster ones. The strings 'fast'
and 'slow'
can be supplied to indicate durations of 200
and 600
milliseconds, respectively. If any other string is supplied, the default duration of 400
milliseconds is used. Unlike the other effect methods, .fadeTo()
requires that duration
be explicitly specified.
If supplied, the callback is fired once the animation is complete. This can be useful for stringing different animations together in sequence. The callback is not sent any arguments, but this
is set to the DOM element being animated. If multiple elements are animated, it is important to note that the callback is executed once per matched element, not once for the animation as a whole.
We can animate any element, such as a simple image:
<div id="clickme"> Click here </div> <img id="book" src="book.png" alt="" width="100" height="123" /> With the element initially shown, we can dim it slowly: $('#clickme').click(function() { $('#book').fadeTo('slow', 0.5, function() { // Animation complete. }); });
With duration
set to 0
, this method just changes the opacity
CSS property, so .fadeTo(0, opacity)
is the same as .css('opacity', opacity)
.
<!DOCTYPE html>
<html>
<head>
<script src="https://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<p>
Click this paragraph to see it fade.
</p>
<p>
Compare to this one that won't fade.
</p>
<script>
$("p:first").click(function () {
$(this).fadeTo("slow", 0.33);
});
</script>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<style>
p { width:80px; margin:0; padding:5px; }
div { width:40px; height:40px; position:absolute; }
div#one { top:0; left:0; background:#f00; }
div#two { top:20px; left:20px; background:#0f0; }
div#three { top:40px; left:40px; background:#00f; }
</style>
<script src="https://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<p>And this is the library that John built...</p>
<div id="one"></div>
<div id="two"></div>
<div id="three"></div>
<script>
$("div").click(function () {
$(this).fadeTo("fast", Math.random());
});
</script>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<style>
div, p { width:80px; height:40px; top:0; margin:0;
position:absolute; padding-top:8px; }
p { background:#fcc; text-align:center; }
div { background:blue; }
</style>
<script src="https://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<p>Wrong</p>
<div></div>
<p>Wrong</p>
<div></div>
<p>Right!</p>
<div></div>
<script>
var getPos = function (n) {
return (Math.floor(n) * 90) + "px";
};
$("p").each(function (n) {
var r = Math.floor(Math.random() * 3);
var tmp = $(this).text();
$(this).text($("p:eq(" + r + ")").text());
$("p:eq(" + r + ")").text(tmp);
$(this).css("left", getPos(n));
});
$("div").each(function (n) {
$(this).css("left", getPos(n));
})
.css("cursor", "pointer")
.click(function () {
$(this).fadeTo(250, 0.25, function () {
$(this).css("cursor", "")
.prev().css({"font-weight": "bolder",
"font-style": "italic"});
});
});
</script>
</body>
</html>