I use the following iScroll 5 code (generally, not so important: just a common scrolling page-by-page):
var myScroll = new IScroll('.scroller', {
mouseWheel: true,
scrollbars: true,
keyBindings: {
// doesn't matter
},
preventDefault: false,
fadeScrollbars: true,
snap: 'section', // <-- that's the key
wheelAction: 'scroll',
});
myScroll.on('beforeScrollStart', function (e) {
myScroll.preventDisabling = true;
});
myScroll.on('scrollMove', function (e) {
});
myScroll.on('scrollStart', function (e) {
// !!! I need the detection somewhere here !!!
if (!myScroll.preventDisabling) {
myScroll.disable();
disabledWasCalledInMeanwhile = true;
}
myScroll.preventDisabling = false;
});
var disabledWasCalledInMeanwhile = false;
// that's just to prevent jumping to another page before scrolling is finished
myScroll.on('scrollEnd', function (e) {
disabledWasCalledInMeanwhile = false;
window.setTimeout(function () {
if (!disabledWasCalledInMeanwhile)
myScroll.enable();
}, 250);
$('.labels>*').toggleClass('active', false)
.eq(this.currentPage.pageY).toggleClass('active', true);
});
myScroll.on('scrollCancel', function (e) {
myScroll.enable();
});
So, is there any chance to detect in beforeScrollStart or scrollStart the page I am going to scroll to? That's important to know for triggering that page items animation.
I've used iScroll for a number of years (it is a excellent library), and I don't know of a built-in method of doing it. All the scroll events (except scrollEnd) before the iScroll snap is determined. However, with a slight modification of the library, I believe it is possible.
First, go into iScroll.js source and find the _nearestSnap method. At the bottom of the method, you will find the object you seek returned. Before the return, grab that data and pass it to a custom event. Unfortunately, iScroll's event system doesn't permit you to pass custom variables to events, so you'll have to do a work-around. In addition, you'll need to track the "flick" event because it won't trigger the _nearestSnap method.
iScroll modification in _nearestSnap method
this.customSnap({
x: x,
y: y,
pageX: i,
pageY: m
});
Update to class instance. Note the addition of "customSnap" method and the flick event.
myScroll = new IScroll('#wrapper', {snap: "p"});
myScroll.customSnap = function(data) {
console.log(data);
};
myScroll.on('flick', function() {
console.log(data.currentPage);
});
That should do it. Not necessarily the cleanest update, but in my testing, it does work.