extension of the backgroundposition in the function animate() dosen't work in IE7 or IE8

Question

This code is extension created by Alexander Farkas http://bit.ly/bZzOC8 It is usefull for could used two values on the function animate() as in this example:

$('div').animate({
   backgroundPosition:'(0 -5500)'
},330);

Unfortunately this extension doesn't work when use IE7 or IE8. The next code is the backgroundPosition extension:

/**
 * @author Alexander Farkas
 * v. 1.02
 */
(function($) {
    $.extend($.fx.step,{
        backgroundPosition: function(fx) {
            if (fx.state === 0 && typeof fx.end == 'string') {
                var start = $.curCSS(fx.elem,'backgroundPosition');
                start = toArray(start);
                fx.start = [start[0],start[2]];
                var end = toArray(fx.end);
                fx.end = [end[0],end[2]];
                fx.unit = [end[1],end[3]];
            }
            var nowPosX = [];
            nowPosX[0] = ((fx.end[0] - fx.start[0]) * fx.pos) + fx.start[0] + fx.unit[0];
            nowPosX[1] = ((fx.end[1] - fx.start[1]) * fx.pos) + fx.start[1] + fx.unit[1];           
            fx.elem.style.backgroundPosition = nowPosX[0]+' '+nowPosX[1];

           function toArray(strg){
               strg = strg.replace(/left|top/g,'0px');
               strg = strg.replace(/right|bottom/g,'100%');
               strg = strg.replace(/([0-9\.]+)(\s|\)|$)/g,"$1px$2");
               var res = strg.match(/(-?[0-9\.]+)(px|\%|em|pt)\s(-?[0-9\.]+)(px|\%|em|pt)/);
               return [parseFloat(res[1],10),res[2],parseFloat(res[3],10),res[4]];
           }
        }
    });
})(jQuery);

the IE debugger finded the error on this line.

strg = strg.replace(/left|top/g,'0px');

I want use this plug-in because the backgroundPositionY or X aren't compatible on firefox and Opera. How to fix the error on IE7 and 8?.

This thread may be what you're looking for (the 2nd answer): http://stackoverflow.com/questions/1780617/ie8-and-jquery-null-pointers/12080450 — dauble, Aug 22 '12 at 20:13
Thanks you very much, if you want you can create an answer and I can accept your response. — Matteo Gilardoni, Aug 23 '12 at 19:43

score 1 · Accepted Answer · edited May 23 '17 at 11:56

It's possible find the solution in this link, IE8 and jQuery null pointers In any case this is the code that fix the ie bug

/**
 * @author Alexander Farkas
 * v. 1.02
 */
(function($){   
    $.extend($.fx.step,{       
        backgroundPosition: function(fx){            
            if (fx.state === 0 && typeof fx.end == 'string'){
                if(navigator.appName == 'Microsoft Internet Explorer'){ //bugfix to IE
                    var start = $.curCSS(fx.elem,'backgroundPositionX');
                    start +=  ' ';
                    start += $.curCSS(fx.elem,'backgroundPositionY');
                }
                else {
                    var start = $.curCSS(fx.elem,'backgroundPosition');
                }
                start = toArray(start);
                fx.start = [start[0],start[2]];
                var end = toArray(fx.end);
                fx.end = [end[0],end[2]];
                fx.unit = [end[1],end[3]];
            }

            var nowPosX = [];
            nowPosX[0] = ((fx.end[0] - fx.start[0]) * fx.pos) + fx.start[0] + fx.unit[0];
            nowPosX[1] = ((fx.end[1] - fx.start[1]) * fx.pos) + fx.start[1] + fx.unit[1];
            fx.elem.style.backgroundPosition = nowPosX[0]+' '+nowPosX[1];

            function toArray(strg){               
                strg = strg.replace(/left|top/g,'0px');
                strg = strg.replace(/right|bottom/g,'100%');
                strg = strg.replace(/([0-9\.]+)(\s|\)|$)/g,"$1px$2");
                var res = strg.match(/(-?[0-9\.]+)(px|\%|em|pt)\s(-?[0-9\.]+)(px|\%|em|pt)/);
                return [parseFloat(res[1],10),res[2],parseFloat(res[3],10),res[4]];
            }        
        }   
    });
})(jQuery);

@Mattea Gilardoni works in IE 7 as well thumbs up for this fix — mirza, Oct 08 '12 at 11:50

extension of the backgroundposition in the function animate() dosen't work in IE7 or IE8

1 Answers1

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