我正在使用jQuery的mousewheel插件,并且我想检测用户何时已经完成使用鼠标滚轮。
类似于可拖动组件中的stop:事件的功能。
有人可以指引我正确的方向吗?
$("#myElem").mousewheel(function() {
clearTimeout($.data(this, 'timer'));
$.data(this, 'timer', setTimeout(function() {
alert("Haven't scrolled in 250ms!");
//do something
}, 250));
});
您可以在此处尝试,我们所做的就是使用 $.data()
在每次使用时存储超时时间,如果在该时间结束之前再次使用,则会清除...否则,您想要运行的任何代码都将被触发,用户已经“完成”了他们想要测试的时间段内的鼠标滚轮使用。请注意保留HTML标签。为了完成Nick Craver的回答:
var wheeldelta = {
x: 0,
y: 0
};
var wheeling;
$('#foo').on('mousewheel', function (e) {
if (!wheeling) {
console.log('start wheeling!');
}
clearTimeout(wheeling);
wheeling = setTimeout(function() {
console.log('stop wheeling!');
wheeling = undefined;
// reset wheeldelta
wheeldelta.x = 0;
wheeldelta.y = 0;
}, 250);
wheeldelta.x += e.deltaFactor * e.deltaX;
wheeldelta.y += e.deltaFactor * e.deltaY;
console.log(wheeldelta);
});
滚动输出:
start wheeling!
Object {x: -1, y: 0}
Object {x: -36, y: 12}
Object {x: -45, y: 12}
Object {x: -63, y: 12}
Object {x: -72, y: 12}
Object {x: -80, y: 12}
Object {x: -89, y: 12}
Object {x: -97, y: 12}
Object {x: -104, y: 12}
Object {x: -111, y: 12}
Object {x: -117, y: 12}
Object {x: -122, y: 12}
Object {x: -127, y: 12}
Object {x: -131, y: 12}
Object {x: -135, y: 12}
Object {x: -139, y: 12}
Object {x: -145, y: 12}
Object {x: -148, y: 12}
Object {x: -152, y: 12}
Object {x: -154, y: 12}
Object {x: -156, y: 12}
Object {x: -157, y: 12}
Object {x: -158, y: 12}
Object {x: -159, y: 12}
Object {x: -161, y: 12}
Object {x: -162, y: 12}
Object {x: -164, y: 12}
Object {x: -166, y: 12}
Object {x: -167, y: 12}
Object {x: -169, y: 12}
stop wheeling!
以下是用纯 JavaScript 实现的方法:
var _scrollTimeout = null;
function onMouseWheel() {
var d = ((typeof e.wheelDelta != "undefined") ? (-e.wheelDelta) : e.detail);
d = 100 * ((d>0)?1:-1);
console.log("Scroll delta", d);
clearTimeout(_scrollTimeout);
_scrollTimeout = setTimeout(function() {
console.log("Haven't scrolled in 250ms");
}, 250);
}
window.addEventListener( 'mousewheel', onMouseWheel, false );
window.addEventListener( 'DOMMouseScroll', onMouseWheel, false ); // firefox
//initialise the new variables
var wheelMap = new Map;
var deltaXEnded = false;
var deltaYEnded = false;
var previousSwipe = Object;
previousSwipe.timeStamp = 0;
previousSwipe.deltaX = 0;
previousSwipe.deltaY = 0;
var wheelstart = false;
var wheelstop = new Event("wheelstop");
function wheelstopcallback(event){
wheelstart = false;
console.log("wheel event has ended");
}
window.addEventListener("wheelstop", wheelstopcallback.bind(this));
window.addEventListener("wheel", normalWheelEventCallbackFunction.bind(this));
滚轮事件回调函数
function normalWheelEventCallbackFunction(event){
if(previousSwipe.timeStamp !== 0){
if(event.timeStamp - previousSwipe.timeStamp < 1000)
wheelMap.set(event.timeStamp, event);
else
wheelMap.clear();
}
else{previousSwipe.timeStamp = event.timeStamp;}
if(event.deltaX > 2 && event.deltaX > previousSwipe.deltaX){
//forward
wheelstart = true
}
else if(event.deltaX < -2&& event.deltaX < previousSwipe.deltaX){
//backward
wheelstart = true;
}
else if(event.deltaY > 2 && event.deltaY > previousSwipe.deltaY){
wheelstart = true;
}
else if(event.deltaY < 2 && event.deltaY < previousSwipe.deltaY){
wheelstart = true;
}
if(
((event.deltaX === 1 || event.deltaX === 0 || event.deltaX === -1) && ((event.deltaX > 0 && event.deltaX < previousSwipe.deltaX) || (event.deltaX < 0 && event.deltaX > previousSwipe.deltaX)) && wheelstart)
|| (wheelstart && (event.deltaX === 0 && previousSwipe.deltaX === 0))
)
{
deltaXEnded = true;
console.log("deltaXEnded");
}
if(
(((event.deltaY === 1 || event.deltaY === 0 || event.deltaY === -1) && ((event.deltaY > 0 && event.deltaY < previousSwipe.deltaY) || (event.deltaY < 0 && event.deltaY > previousSwipe.deltaY))) && wheelstart)
|| (wheelstart && (event.deltaY === 0 && previousSwipe.deltaY === 0))) {
deltaYEnded = true;
console.log("deltaYEnded");
}
if(deltaXEnded && deltaYEnded){
deltaXEnded = false;
deltaYEnded = false;
window.dispatchEvent(wheelstop);
}
previousSwipe.deltaX = event.deltaX;
previousSwipe.deltaY = event.deltaY;
}
这段代码可能有一些错误,但大部分逻辑还是比较合理的。如果你需要捕获每个滚轮事件,建议添加备用方案,因为有些事件可能会在“wheelstop”事件之后触发。
最后,请确保实现了处理程序,以防被点击事件打断滚轮事件...
function wheelstopdispatch(){
if(wheelstart)
window.dispatchEvent(wheelstop);
}
window.addEventListener("click", wheelstopdispatch);
// do something
时有小延迟(250毫秒)。更好的选择是立即执行您的代码,然后在等待delay
毫秒之后再捕获进一步事件。processing
,将其初始化为false
,并在代码执行前后切换其值。window.processing = false;
$("#myElem").mousewheel(function() {
if (processing === false) {
processing = true;
// do something
setTimeout(function() {
processing = false;
}, 250)); // waiting 250ms to change back to false.
}
});