装备事宜
orientationchange
事宜
该事宜的window.orientation
属性中包括3个值:0示意肖像形式、90示意左扭转的横向形式、-90示意右扭转的横向形式。event对象不包括任何信息:
window.onload = function () {
var div = document.getElementById("info");
div.innerHTML = "Current orientation is " + window.orientation;
};
window.addEventListener("orientationchange", function () {
div.innerHTML = "Current orientation is " + window.orientation;
});
deviceorientationevent
事宜
MozOrientation
事宜,该事宜已被移除,应当运用DeviceOrientationEvent
事宜
Warning: This experimental API was removed in Gecko 6.0 (Firefox 6.0 / Thunderbird 6.0 / SeaMonkey 2.3), when support for the standard DeviceOrientationEvent was implemented. You should use that API instead.
然则DeviceOrientationEvent事宜仍然是实验性的事宜,现在有部份浏览器临时不支持。
该事宜的企图是通知开发者装备在空间中朝向哪儿,装备在三维空间中是靠x、y、z轴来定位的。
事宜对象包括:
alpha:缭绕z轴扭转,y轴的度数差;0~360的值;
beta:缭绕x轴扭转,z轴的度数差;-180~180的值;
gamma:缭绕y轴扭转,z轴的度数差;-90~90的值;
absolute:示意装备是不是返回一个绝对值;
compassCalibrated:示意装备的指南针是不是校准过;
如:
<div id="info">丄</div>
window.addEventListener("deviceorientation", function () {
var info = document.getElementById("info");
info.style.webkitTransform = "rotate(" + -Math.round(event.alpha) + "deg)";
});
devicemotion
事宜
该事宜是要通知开发者装备什么时候挪动,如经由过程该事宜检测装备是不是在往下掉,是不是被走着的人拿在手里等等。
属性:
acceleration:包括x、y、z属性的对象,不斟酌重力的情况下,每一个方向的加速度;
accelerationIncludingGravity:包括x、y、z属性的对象,在斟酌z天然重力加速度的情况下,每一个方向上的加速度;
interval:毫秒值,必须在另一个devicemotion事宜触发前传入;
rotationRate:包括示意方向的alpha、beta和gamma属性的对象;
假如读取不到值,会返回null,所以应当先检测它们的值是不是为null:
window.addEventListener("devicemotion", function () {
if (event.rotationRate !== null) {
// statement
}
});
触摸与手势事宜
触摸事宜
兼容DOM的触摸事宜
touchstart:触摸屏幕时触发;
touchmove:滑动时触发,挪用preventDefault()函数可阻挠转动;
touchend:当手指从屏幕上移开时触发;
touchcancel:当体系住手跟踪触摸时触发;
上面的事宜都邑冒泡,都可以作废。每一个触摸事宜的event对象都供应了在鼠标事宜中常见的属性。
跟踪触摸的事宜
touches:示意当前跟踪的触摸操纵的Touch对象的数组;
targetTouches:特定于事宜目的的Touch对象的数组;
changedTouches:示意自上次触摸以来发生了什么转变的Touch对象的数组;
每一个Touch对象包括的属性:
clientX:视口中的x坐标;
clientY:;
identifier:标识触摸的唯一ID;
pageX:触摸目的在页面中的x坐标;
pageY:;
screenX:触摸目的在屏幕中的x坐标;
screenY:;
target:触摸DOM节点目的;
如:
function handleTouchEvent () {
if (event.touches.length == 1) {
var output = document.getElementById("output");
switch (event.type) {
case "touchstart":
output.innerHTML = "Touch started (" + event.touches[0].clientX + "," + event.touches[0].clientY + ")";
break;
case "touchmove":
event.preventDefault();
output.innerHTML = "Touch moved (" + event.changedTouches[0].clientX + "," + event.changedTouches[0].clientY + ")";
break;
case "touchend":
output.innerHTML = "Touch ended (" + event.changedTouches[0].clientX + "," + event.changedTouches[0].clientY + ")";
break;
}
}
}
window.addEventListener("touchstart", handleTouchEvent);
window.addEventListener("touchmove", handleTouchEvent);
window.addEventListener("touchend", handleTouchEvent);
临时不清楚为何touchend无回响反映。
手势事宜
gesturestart:当一个手指已按在屏幕上而另一个手指又触摸屏幕时触发;
gesturechange:当触摸屏幕的任何一个手指的位置发生变化时触发;
gestureend:当任何一个手指从屏幕上面移开时触发;
个中event还包括除鼠标事宜的属性以外别的两个属性:rotation
和scale
:个中rotation属性示意扭转的角度,从0最先,负值示意逆时针扭转,正值示意顺时针扭转;scale属性从1最先,跟着间隔拉大而增添,跟着间隔减少而减小:
var output = document.getElementById("output");
document.addEventListener("gesturestart", function () {
output.innerHTML = "rotation: " + event.rotation + ";" + "scale: " + event.scale;
});
document.addEventListener("gestureend", function () {
output.innerHTML = "rotation: " + event.rotation + ";" + "scale: " + event.scale;
});
document.addEventListener("gesturechange", function () {
event.preventDefault();
output.innerHTML = "rotation: " + event.rotation + ";" + "scale: " + event.scale;
});
写成:
function handleGestureEvent() {
var output = document.getElementById("output");
switch (event.type) {
case "gesturestart":
output.innerHTML = "rotation: " + event.rotation + ";" + "scale: " + event.scale;
break;
case "gestureend":
output.innerHTML = "rotation: " + event.rotation + ";" + "scale: " + event.scale;
break;
case "gesturechange":
event.preventDefault();
output.innerHTML = "rotation: " + event.rotation + ";" + "scale: " + event.scale;
break;
}
}
document.addEventListener("gesturestart", handleGestureEvent);
document.addEventListener("gestureend", handleGestureEvent);
document.addEventListener("gesturechange", handleGestureEvent);