html5 web 摇一摇切换歌曲

 1 <!DOCTYPE html>  
 2 <html lang="en">  
 3 <head>  
 4     <meta charset="utf-8" />  
 5     <meta name="viewport" content="width=device-width, initial-scale=1.0" />  
 6     <title>摇一摇功能</title>  
 7 </head>  
 8 <body onload="init()">  
 9 <p>用力摇一摇你手机</p>  
10 <audio id="musicBox" controls src=""/>  
11 </body>  
12 </html>  
13 <script type="text/javascript">  
14         //Javascript  
15         var SHAKE_THRESHOLD = 3000;  
16         var last_update = 0;  
17         var x = y = z = last_x = last_y = last_z = 0;  
18         function init() {  
19             if (window.DeviceMotionEvent) {  
20                 window.addEventListener('devicemotion', deviceMotionHandler, false);  
21             } else {  
22                 alert('not support mobile event');  
23             }  
24         }  
25         function deviceMotionHandler(eventData) {  
26             var acceleration = eventData.accelerationIncludingGravity;  
27             var curTime = new Date().getTime();  
28             if ((curTime - last_update) > 100) {  
29                 var diffTime = curTime - last_update;  
30                 last_update = curTime;  
31                 x = acceleration.x;  
32                 y = acceleration.y;  
33                 z = acceleration.z;  
34                 var speed = Math.abs(x + y + z - last_x - last_y - last_z) / diffTime * 10000;  
35   
36                 if (speed > SHAKE_THRESHOLD) {  
37                  alert("摇动了，播放");
38                     var media=document.getElementById("musicBox");//获取音频控件
39                     media.setAttribute("src","http://1.html5weby1y.sinaapp.com/2.mp3");
40                     media.load();//加载音频
41                     media.play();//播放音频 
42                 }  
43                 last_x = x;  
44                 last_y = y;  
45                 last_z = z;  
46             }  
47         }  
48     </script>