利用HTML5的devicemotion事件实现手机摇一摇抽奖,年会抽奖
摇一摇JS脚本逻辑:
接下来是移动端JS脚本逻辑的实现,摇一摇的实现需借助html5新增的devicemotion事件,获取设备在位置和方向上的改变速度的相关信息,该事件的基本使用如下:
if (window.DeviceMotionEvent) { window.addEventListener('devicemotion', handler, !1); lastTime = new Date(); } else { alert('你的浏览器不支持摇一摇功能.'); }
devicemotion事件对象中有一个accelerationIncludingGravity属性,该属性包括:一个包含x、y 和z 属性的对象,在考虑z 轴自然重力加速度的情况下,告诉你在每个方向上的加速度。该API的具体使用大家可以参考网上的资料,非常多,这里就不重复了。 摇一摇的具体逻辑如下:
function handler(e) { var current = e.accelerationIncludingGravity; var currentTime; var timeDifference; var deltaX = 0; var deltaY = 0; var deltaZ = 0; //记录上一次设备在x,y,z方向上的加速度 if ((lastX === null) && (lastY === null) && (lastZ === null)) { lastX = current.x; lastY = current.y; lastZ = current.z; return; } //得到两次移动各个方向上的加速度绝对差距 deltaX = Math.abs(lastX - current.x); deltaY = Math.abs(lastY - current.y); deltaZ = Math.abs(lastZ - current.z); //当差距大于设定的阀值并且时间间隔大于指定阀值时,触发摇一摇逻辑 if (((deltaX > threshold) && (deltaY > threshold)) || ((deltaX > threshold) && (deltaZ > threshold)) || ((deltaY > threshold) && (deltaZ > threshold))) { currentTime = new Date; timeDifference = currentTime.getTime() - lastTime.getTime(); //时间间隔 if (timeDifference > timeout) { //触发摇一摇事件 dealShake(); lastTime = new Date; } } lastX = current.x; lastY = current.y; lastZ = current.z; }
不考虑各等奖的中奖概率问题
最终完整代码示例:
![](https://images.cnblogs.com/OutliningIndicators/ExpandedBlockStart.gif)
1 <!DOCTYPE html> 2 <html> 3 <head> 4 <meta charset="UTF-8"> 5 <meta name="viewport" content="width=device-width,initial-scale=1.0,maximum-scale=1.0,minimum-scale=1.0,user-scalable=no"> 6 <title>摇一摇抽奖</title> 7 <style type="text/css"> 8 html,body{ width:100%; height:100%; background-color: #000; margin:0; overflow: hidden;} 9 .tip{ position: absolute; bottom: 30px; left: 10px; color: #fff; font-family: '楷体'; text-align: center; right: 10px; height: 32px; line-height: 32px; background-color: rgba(255,255,255,.4); border-radius: 3px; } .tip.active{ -webkit-animation: jump 1.5s linear; animation: jump 1s linear; } 10 </style> 11 </head> 12 <body> 13 <div class="tip" id="tip"> </div> 14 15 <script type="text/javascript"> 16 var lastX = null, 17 lastY = null, 18 lastZ = null; 19 var threshold = 3; //灵敏度(值越小灵敏度越高) 20 var timeout = 1000; 21 var lastTime = null; 22 var isShaking = !1; 23 document.addEventListener('DOMContentLoaded', function (e) { 24 ready(); 25 }, !1); 26 27 /*脚本逻辑: 28 *移动端JS脚本逻辑的实现,摇一摇的实现需借助html5新增的devicemotion事件,获取设备在位置和方向上的改变速度的相关信息。 29 *devicemotion事件对象中有一个accelerationIncludingGravity属性,该属性包括:一个包含x、y 和z 属性的对象,在考虑z 轴自然重力加速度的情况下,告诉你在每个方向上的加速度。 30 */ 31 function ready() { 32 if (window.DeviceMotionEvent) { 33 window.addEventListener('devicemotion', handler, !1); 34 lastTime = new Date(); 35 } else { 36 alert('你的浏览器不支持摇一摇功能.'); 37 } 38 } 39 40 function handler(e) { 41 var current = e.accelerationIncludingGravity; 42 var currentTime; 43 var timeDifference; 44 var deltaX = 0; 45 var deltaY = 0; 46 var deltaZ = 0; 47 48 //记录上一次设备在x,y,z方向上的加速度 49 if ((lastX === null) && (lastY === null) && (lastZ === null)) { 50 lastX = current.x; 51 lastY = current.y; 52 lastZ = current.z; 53 return; 54 } 55 56 //得到两次移动各个方向上的加速度绝对差距 57 deltaX = Math.abs(lastX - current.x); 58 deltaY = Math.abs(lastY - current.y); 59 deltaZ = Math.abs(lastZ - current.z); 60 //当差距大于设定的阀值并且时间间隔大于指定阀值时,触发摇一摇逻辑 61 if (((deltaX > threshold) && (deltaY > threshold)) || ((deltaX > threshold) && (deltaZ > threshold)) || ((deltaY > threshold) && (deltaZ > threshold))) { 62 currentTime = new Date; 63 timeDifference = currentTime.getTime() - lastTime.getTime(); 64 //时间间隔 65 if (timeDifference > timeout) { 66 //触发摇一摇事件 67 dealShake(); 68 lastTime = new Date; 69 } 70 } 71 72 lastX = current.x; 73 lastY = current.y; 74 lastZ = current.z; 75 } 76 77 function dealShake() { 78 if (isShaking) return; 79 isShaking = !0; 80 81 document.getElementById("tip").innerHTML = "恭喜您,摇中:" + GetName(); 82 83 setTimeout(function () { 84 isShaking = !1; 85 document.getElementById("tip").innerHTML = " "; 86 }, 1000); 87 88 } 89 90 function GetName() { 91 var chars = ["一等奖", "二等奖", "三等奖", "四等奖", "五等奖"]; 92 return chars[GetRandom(0, chars.length - 1)]; 93 } 94 function GetRandom(minValue, maxValue) { 95 return Math.round(Math.random() * (maxValue - minValue)) + minValue; 96 } 97 </script> 98 99 </body>