Ese es el JAVASCRIPT
/******
* History
* 2002-02-08 1.7 If the ON image is already loaded don't reload it.
* This should help with the IE bug that reloads images
* from the server even though they are pre-cached.
* (will not work for swapping multiple pictures into same Image object)
* 2002-02-13 1.8 Corrected a bug in JSFX.findImg
* 2002-04-23 1.9 Write out the style tag.
* 2002-06-09 1.10 Attempt fix for IE on a Mac
* 2002-08-27 1.11 Fix a bug whereby opacity may go over 100 which
* may be causing a bug in IE6
* 2002-08-29 1.12 Thanks to piglet (
http://homepage.ntlworld.com/thepiglet/)
* I now have a partial fix for NS7 and Mozilla 1.1.
************************************************** *********************/
/****** User may alter these to change the fade effect ********/
var FadeInStep = 15;
var FadeOutStep = 20;
/****** Don't alter anything else **************/
document.write('<STYLE TYPE="text/css">.imgFader{ position:relative; filter:alpha(opacity=0); -moz-opacity:0.0 }</STYLE>');
if(!window.JSFX)
JSFX=new Object();
JSFX.RolloverObjects=new Array();
JSFX.Rollover = function(name, img)
{
JSFX.RolloverObjects[name]=new Image();
JSFX.RolloverObjects[name].img_src = img;
if(!JSFX.Rollover.postLoad)
JSFX.RolloverObjects[name].src = img;
}
JSFX.Rollover.postLoad = false;
JSFX.Rollover.loadImages = function()
{
var i;
for(i in JSFX.RolloverObjects)
{
r=JSFX.RolloverObjects[i];
r.src=r.img_src;
}
}
JSFX.Rollover.error = function(n)
{
alert("JSFX.Rollover - An Error has been detected\n"
+ "----------------------------------\n"
+ "You must define a JSFX.Rollover in your document\n"
+ "JSFX.Rollover(\""+n+"\",\"your_on_img.gif\")\ n"
+ "(check the spelling of your JSFX.Rollovers)");
}
/************************************************** *****************
*
* Function : getImg
*
* Description : In Netscape 4 images could be in layers so we might
* have to recurse the layers to find the image
*
*********/
JSFX.getImg = function(n, d)
{
var img = d.images[n];
if(!img && d.layers)
for(var i=0 ; !img && i<d.layers.length ; i++)
img=JSFX.getImg(n,d.layers[i].document);
return img;
}
/************************************************** *****************
*
* Function : findImg
*
* Description : gets the image from the document and reports an
* error if it cannot find it.
*
********************/
JSFX.findImg = function(n, d)
{
var img = JSFX.getImg(n, d);
/*** Stop emails because the image was named incorrectly ***/
if(!img)
{
alert("JSFX.findImg - An Error has been detected\n"
+ "----------------------------------\n"
+ "You must define an image in your document\n"
+ "<IMG SRC=\"your_image.ext\" NAME=\""+n+"\">\n"
+ "(check the NAME= attribute of your images)");
return(new Image());
}
return img;
}
JSFX.ImageFadeRunning=false;
JSFX.ImageFadeInterval=30;
/********************
*
* Function : imgFadeIn
*
* Description : This function is based on the turn_on() function
* of animate2.js (animated rollovers from
www.roy.whittle.com).
* Each image object is given a state.
* OnMouseOver the state is switched depending on the current state.
* Current state -> Switch to
* ===========================
* null -> OFF.
* OFF -> FADE_IN
* FADE_OUT -> FADE_IN
* FADE_OUT -> FADE_OUT_IN (if the new image is different)
* FADE_IN_OUT-> FADE_IN (if the image is the same)
************/
JSFX.imgFadeIn = function(img, imgSrc)
{
if(img)
{
if(img.state == null)
{
img.state = "OFF";
img.index = 0;
img.next_on = null;
}
if(img.state == "OFF")
{
/*** Vers 1.7 only load the ON image once ever ***/
if(img.src.indexOf(imgSrc) == -1)
img.src=imgSrc;
img.currSrc = imgSrc;
img.state = "FADE_IN";
JSFX.startFading();
}
else if( img.state == "FADE_IN_OUT"
|| img.state == "FADE_OUT_IN"
|| img.state == "FADE_OUT")
{
if(img.currSrc == imgSrc)
img.state = "FADE_IN";
else
{
img.next_on = imgSrc;
img.state="FADE_OUT_IN";
}
}
}
}
/********************
*
* Function : imgFadeOut
*
* Description : This function is based on the turn_off function
* of animate2.js (animated rollovers from
www.roy.whittle.com).
* Each image object is given a state.
* OnMouseOut the state is switched depending on the current state.
* Current state -> Switch to
* ===========================
* ON -> FADE_OUT.
* FADE_IN -> FADE_IN_OUT.
* FADE_OUT_IN -> FADE_IN. (after swapping to the next image)
**********************/
JSFX.imgFadeOut = function(img)
{
if(img)
{
if(img.state=="ON")
{
img.state="FADE_OUT";
JSFX.startFading();
}
else if(img.state == "FADE_IN")
{
img.state="FADE_IN_OUT";
}
else if(img.state=="FADE_OUT_IN")
{
img.next_on == null;
img.state = "FADE_OUT";
}
}
}
/****************
*
* Function : startFading
*
* Description : This function is based on the start_animating() function
* of animate2.js (animated rollovers from
www.roy.whittle.com).
* If the timer is not currently running, it is started.
* Only 1 timer is used for all objects
************************************************** ***************/
JSFX.startFading = function()
{
if(!JSFX.ImageFadeRunning)
JSFX.ImageFadeAnimation();
}
/*****************************
*
* Function : ImageFadeAnimation
*
* Description : This function is based on the Animate function
* of animate2.js (animated rollovers from
www.roy.whittle.com).
* Each image object has a state. This function
* modifies each object and (possibly) changes its state.
*****************************/
JSFX.ImageFadeAnimation = function()
{
JSFX.ImageFadeRunning = false;
for(i=0 ; i<document.images.length ; i++)
{
var img = document.images[i];
if(img.state)
{
if(img.state == "FADE_IN")
{
img.index+=FadeInStep;
if(img.index > 100)
img.index = 100;
if(img.filters)
img.filters.alpha.opacity = img.index;
else
img.style.MozOpacity = img.index/101;
if(img.index == 100)
img.state="ON";
else
JSFX.ImageFadeRunning = true;
}
else if(img.state == "FADE_IN_OUT")
{
img.index+=FadeInStep;
if(img.index > 100)
img.index = 100;
if(img.filters)
img.filters.alpha.opacity = img.index;
else
img.style.MozOpacity = img.index/101;
if(img.index == 100)
img.state="FADE_OUT";
JSFX.ImageFadeRunning = true;
}
else if(img.state == "FADE_OUT")
{
img.index-=FadeOutStep;
if(img.index < 0)
img.index = 0;
if(img.filters)
img.filters.alpha.opacity = img.index;
else
img.style.MozOpacity = img.index/101;
if(img.index == 0)
img.state="OFF";
else
JSFX.ImageFadeRunning = true;
}
else if(img.state == "FADE_OUT_IN")
{
img.index-=FadeOutStep;
if(img.index < 0)
img.index = 0;
if(img.filters)
img.filters.alpha.opacity = img.index;
else
img.style.MozOpacity = img.index/101;
if(img.index == 0)
{
img.src = img.next_on;
img.currSrc = img.next_on;
img.state="FADE_IN";
}
JSFX.ImageFadeRunning = true;
}
}
}
/*** Check to see if we need to animate any more frames. ***/
if(JSFX.ImageFadeRunning)
setTimeout("JSFX.ImageFadeAnimation()", JSFX.ImageFadeInterval);
}
/**********************
*
* Function : hasOpacity
*
* Description : Tests if the browser allows Opacity
*
************************************************** ***************/
JSFX.hasOpacity = function(obj)
{
if(document.layers)
return false;
if(window.opera)
return false;
if(navigator.userAgent.toLowerCase().indexOf("mac" ) != -1)
return false;
return true;
}
/************************************************** *****************
*
* Function : fadeIn /fadeOut
*
* Description : Detects browser that can do opacity and fades the images
* For browsers that do not support opacity it just does an image swap.
* (I only know about NS4 but maybe IE on a Mac also ?)
* For these functions to work you need to name the image
* e.g. for an image named "home" you need
* <IMG .... NAME="home">
* and you need 2 images, the on and the off image
**************/
JSFX.fadeIn = function(imgName, rollName)
{
if(rollName == null)
rollName=imgName;
/*** Stop emails because the rollover was named incorrectly ***/
if(!JSFX.RolloverObjects[rollName])
{
JSFX.Rollover.error(rollName);
return;
}
var img = JSFX.findImg(imgName, document);
if(JSFX.hasOpacity(img))
JSFX.imgFadeIn(img, JSFX.RolloverObjects[rollName].img_src);
else
{
if(img.offSrc==null)
img.offSrc=img.src;
img.src=JSFX.RolloverObjects[rollName].img_src;
}
}
JSFX.fadeOut = function(imgName)
{
var img = JSFX.findImg(imgName, document);
if(JSFX.hasOpacity(img))
JSFX.imgFadeOut(img);
else
img.src=img.offSrc;
}
/**********************
*
* Function : imgOn /imgOff
*
* Description : Included these functions so you can mix simple and
* fading rollovers without having to include 2 ".js" files
*
*********************/
JSFX.imgOn = function(imgName, rollName)
{
if(rollName == null)
rollName=imgName;
/*** Stop emails because the rollover was named incorrectly ***/
if(!JSFX.RolloverObjects[rollName])
{
JSFX.Rollover.error(rollName);
return;
}
var img = JSFX.findImg(imgName,document);
if(img.offSrc==null)
img.offSrc=img.src;
img.src=JSFX.RolloverObjects[rollName].img_src;
}
JSFX.imgOff = function(imgName)
{
var img = JSFX.findImg(imgName,document);
img.src=img.offSrc;
}