开发豆丸（http://douwan.tudou.com/）时做的slider组件

gistfile1.js

/**
 * TUI::ui::slider
 * @created: Dexter.Yy
 * @modified: $Author$ 
 * @version: $Rev$
 */

/**
 * 滑块组件
 * @class TUI.widget.slider
 */ 
TUI.newModule("TUI.widget.slider", function(sandbox, $, TUI){
    var Slider = {
        event: {},
        setByValue: function(v, anime){
            this.value = v;
            this.rank = parseInt( ( v - this.start ) / this.step );
            this.change(anime);
        },
        setByRank: function(r, anime){
            this.rank = r;
            this.value = this.start + this.rank * this.step;
            this.change(anime);
        },
        change: function(anime){
            var dist = this.stepWidth * this.rank;
            if (anime || this.anime)
                $(this.block).animate({ left: dist }, 100, "easeOutQuad");
            else
                this.block.style.left = dist + "px";
            /**
             * 滑块的值发生改变
             * @event change
             */  
            this.event.fire("change", [this.value, this.rank]);
        }
    };
    return function(op){
        var o = TUI.clone(Slider);
        $.extend(o, op);
        o.event = new TUI.eventClass();
        var t = o.track;
        var s = o.block = t.firstChild;
        var blockWidth = s.offsetWidth || parseInt($(s).css("width"));
        var rangeWidth = ( t.offsetWidth || parseInt($(t).css("width")) ) - blockWidth;
        o.stepWidth = Math.abs(o.step) / ( o.max - o.min ) * rangeWidth;
        o.start = o.step > 0 ? o.min : o.max;
        o.setByValue(o.initial);

        var start;
        var mousemove = function(e){
            if (!start) {
                $(document).unbind("mousemove", mousemove);
                return false;
            }
            var m = o;
            var end = e.pageX;
            var n = parseInt( ( end - start ) / m.stepWidth ); 
            if ( Math.abs(n) > 1 ) {
                var rank = m.rank + n;
                var v = m.start + rank * m.step;
                if (v <= m.max && v >= m.min) {
                    m.setByValue(v);
                    start = end;
                }
            }
        };
        var mouseup = function(){
            start = null;
            $(document).unbind("mousemove", mousemove).unbind("mouseup", mouseup);  
            /**
             * 鼠标释放滑块
             * @event release
             */ 
            o.event.fire("release", [o.value, o.rank]);
        };
        $(s).mousedown(function(e){
            e.preventDefault();
            start = e.pageX;
            $(document).mousemove(mousemove).mouseup(mouseup);
        }).click(function(){
            return false;   
        });
        $(t).click(function(e){
            var d = e.pageX - TUI.pos.elementLeft(t) - blockWidth / 2;
            if ( d > rangeWidth )
                d = rangeWidth;
            else if ( d < 0 )
                d = 0;
            var rank = parseInt(d / o.stepWidth);
            o.setByRank(rank, true);
            o.event.fire("release", [o.value, o.rank]);
        });

        return o;
    };
}, [jQuery, TUI]);