First look at css hooks. These hooks provide a way to change how jQuery handles getting and setting certain css properties. This means normalizing properties like background-position can easily be done via plugins.

They are similar in concept to the special event hooks. Return false from the hook to revert control back to jQuery's normal processes for getting and setting certain css properties.
This commit is contained in:
Brandon Aaron 2010-09-02 21:06:40 -05:00
parent 97cbd76695
commit 65b24861bc

View file

@ -25,7 +25,7 @@ jQuery.fn.css = function( name, value ) {
if ( value === undefined ) {
return jQuery.curCSS( elem, name );
}
if ( typeof value === "number" && !rexclude.test(name) ) {
value += "px";
}
@ -35,6 +35,42 @@ jQuery.fn.css = function( name, value ) {
};
jQuery.extend({
cssHooks: {
opacity: {
get: function( elem, force ) {
var style = elem.style;
if ( jQuery.support.opacity && !style.filter ) {
return false; // move along, nothing to see here
}
// IE uses filters for opacity
var ret = ropacity.test(elem.currentStyle.filter || "") ?
(parseFloat(RegExp.$1) / 100) + "" :
"";
return ret === "" ?
"1" :
ret;
},
set: function( elem, value ) {
var style = elem.style;
if ( jQuery.support.opacity && !style.filter ) {
return false; // move along, nothing to see here
}
// IE has trouble with opacity if it does not have layout
// Force it by setting the zoom level
style.zoom = 1;
// Set the alpha filter to set the opacity
var opacity = parseInt( value, 10 ) + "" === "NaN" ? "" : "alpha(opacity=" + value * 100 + ")";
var filter = style.filter || jQuery.curCSS( elem, "filter" ) || "";
style.filter = ralpha.test(filter) ? filter.replace(ralpha, opacity) : opacity;
}
}
},
style: function( elem, name, value ) {
// don't set styles on text and comment nodes
if ( !elem || elem.nodeType === 3 || elem.nodeType === 8 ) {
@ -48,24 +84,6 @@ jQuery.extend({
var style = elem.style || elem, set = value !== undefined;
// IE uses filters for opacity
if ( !jQuery.support.opacity && name === "opacity" && style.filter ) {
if ( set ) {
// IE has trouble with opacity if it does not have layout
// Force it by setting the zoom level
style.zoom = 1;
// Set the alpha filter to set the opacity
var opacity = parseInt( value, 10 ) + "" === "NaN" ? "" : "alpha(opacity=" + value * 100 + ")";
var filter = style.filter || jQuery.curCSS( elem, "filter" ) || "";
style.filter = ralpha.test(filter) ? filter.replace(ralpha, opacity) : opacity;
}
return style.filter && style.filter.indexOf("opacity=") >= 0 ?
(parseFloat( ropacity.exec(style.filter)[1] ) / 100) + "":
"";
}
// Make sure we're using the right name for getting the float value
if ( rfloat.test( name ) ) {
name = styleFloat;
@ -73,8 +91,19 @@ jQuery.extend({
name = name.replace(rdashAlpha, fcamelCase);
var hooks = jQuery.cssHooks[name] || {};
if ( set ) {
style[ name ] = value;
if ( !('set' in hooks) || hooks.set( elem, value ) === false ) {
style[ name ] = value;
}
}
if ( 'get' in hooks ) {
var cssHookReturn = hooks.get( elem, false );
if ( cssHookReturn !== false ) {
return cssHookReturn;
}
}
return style[ name ];
@ -98,24 +127,17 @@ jQuery.extend({
},
curCSS: function( elem, name, force ) {
var ret, style = elem.style, filter;
// IE uses filters for opacity
if ( !jQuery.support.opacity && name === "opacity" && elem.currentStyle ) {
ret = ropacity.test(elem.currentStyle.filter || "") ?
(parseFloat(RegExp.$1) / 100) + "" :
"";
return ret === "" ?
"1" :
ret;
}
var ret, style = elem.style, filter, hooks = jQuery.cssHooks[name] || {};
// Make sure we're using the right name for getting the float value
if ( rfloat.test( name ) ) {
name = styleFloat;
}
if ( 'get' in hooks && ( ret = hooks.get( elem, force ) ) !== false ) {
return ret;
}
if ( !force && style && style[ name ] ) {
ret = style[ name ];