var SHAKE_THRESHOLD = 800;//摇动强度var lastUpdate = 0;var x, y, z, last_x, last_y, last_z;var canshake = false;function deviceMotionHandler(eventData) {    var acceleration = eventData.accelerationIncludingGravity;    var curTime = new Date().getTime();    if ((curTime - lastUpdate) > 100) {        var diffTime = (curTime - lastUpdate);        lastUpdate = curTime;        x = acceleration.x;        y = acceleration.y;        z = acceleration.z;        var speed = Math.abs(x + y + z - last_x - last_y - last_z) / diffTime * 10000;        if (canshake && speed > SHAKE_THRESHOLD) {            canshake = false;            //DO STH　　　　　　　if (window.DeviceMotionEvent) { window.removeEventListener(‘devicemotion‘, deviceMotionHandler, false); }        }        last_x = x;        last_y = y;        last_z = z;    }}