http://www.stoneandstang.com/themes/mobile/static/js/cart_icon.js

1$(document).ready(function() {//panmove
2    var tb = false;
3    function panmove(){
4        var pan_in=$(".site_nav");
5        var scr_w=parseInt($(".allpage").width())-parseInt($(".site_btn").width());
6        var scr_h=parseInt($(".allpage").height())-parseInt($(".site_btn").height());
7        var half_w=parseInt(parseInt($(".allpage").width())/2);
8        var half_h=parseInt(parseInt($(".allpage").height())/2);
9        var isdrag=false;
10        var tx,ty,x,y,n,m;
11        function movemouse(e){
12            if(isdrag){
13                if((tx+e.touches[0].pageX-x)>scr_w){
14                    n=scr_w;
15                    tb = true;
16                }else{
17                    n=(tx+e.touches[0].pageX-x)>0?(tx+e.touches[0].pageX-x):0;
18                    if(n<=half_w){ // 小于50%
19                        pan_in.css("right","auto");
20                        pan_in.css("left","100%");
21                        tb = false;
22                    }else{ // 大于50%
23                        pan_in.css("left","auto");
24                        pan_in.css("right","100%");
25                        tb = true;
26                    }
27                }
28                if((ty+e.touches[0].pageY-y)>scr_h){
29                    m=scr_h;
30                    pan_in.css("top","auto");
31                    pan_in.css("bottom","100%");
32                }else{
33                    m=(ty+e.touches[0].pageY-y)>0?(ty+e.touches[0].pageY-y):0;
34                    if(m<=half_h){ // 大于50% 屏幕底部
35                        pan_in.css("top","0");
36                        pan_in.css("bottom","auto");
37                    }else{
38                        pan_in.css("top","auto");
39                        pan_in.css("bottom","100%");
40                    }
41                }
42                $("#pbtn-nav").css("left",n);
43                $("#pbtn-nav").css("top",m);
44                e.preventDefault();
45            }
46            pan_in.removeClass("slideup");
47            pan_in.removeClass("slidedown");
48        }
49        function selectmouse(e){
50            isdrag=true;
51            tx=parseInt($(".site_btn").css("left"));
52            ty=parseInt($(".site_btn").css("top"));
53            x=e.touches[0].pageX;
54            y=e.touches[0].pageY;
55            e.preventDefault();
56        }
57        document.getElementById("pbtn-nav").addEventListener('touchend',function(){isdrag=false;});
58        document.getElementById("pbtn-nav").addEventListener('touchstart',selectmouse);
59        document.getElementById("pbtn-nav").addEventListener('touchmove',movemouse);
60    }
61    //panmove();
62    $("#pbtn-nav").click(function(){
63        if(tb == true){
64            $(".site-nav").toggleClass("slidedown");
65        }else{
66            $(".site-nav").toggleClass("slideup");
67        }
68    });
69});