jQuery Mobile 1.4 infinite scrolling: Window scroll not firing

Question

In jQuery Mobile 1.4, why isn't $(window).scroll firing? Here's a non-working example trying to detect when the user has scrolled to the end of the page:

http://jsfiddle.net/5x6T2/

$(document).on('pagecontainershow', function () {
    $(window).scroll(function () {
        if ($(window).scrollTop() + $(window).height() == $(document).height()) {
            alert("Bottom reached!");
        }
    });
});

This was all working fine in jQuery Mobile 1.3 prior to the deprecation of pageshow:

http://jsfiddle.net/Demr7/

$(document).on('pageshow', '.ui-page', function() {
    $(window).scroll(function () {
        if ($(window).scrollTop() + $(window).height() == $(document).height()) {
            alert("Bottom reached!");
        }
    });
});

Anybody know what to do?

Answer 1

You don't have to use any third party plugin to achieve infinity scrolling. You simply need to listen to either scrollstart or scrollstop and do some math.

What you need is $(window).scrollTop(), $.mobile.getScreenHeight(), $(".ui-content").outerHeight(), $(".ui-header").outerHeight() and $(".ui-footer").outerHeight().

When $(window).scrollTop()'s value matches the value of viewport's height minus content div's height plus toolbars height, it means you have reached the bottom of the page.

Note that you should remove 1px of retrieved height of each fixed toolbars.

Attach scrollstop listener to document and then define heights variables.

$(document).on("scrollstop", function (e) {

        /* active page */
    var activePage = $.mobile.pageContainer.pagecontainer("getActivePage"),

        /* window's scrollTop() */
        scrolled = $(window).scrollTop(),

        /* viewport */
        screenHeight = $.mobile.getScreenHeight(),

        /* content div height within active page */
        contentHeight = $(".ui-content", activePage).outerHeight(),

        /* header's height within active page (remove -1 for unfixed) */
        header = $(".ui-header", activePage).outerHeight() - 1,

        /* footer's height within active page (remove -1 for unfixed) */
        footer = $(".ui-footer", activePage).outerHeight() - 1,

        /* total height to scroll */
        scrollEnd = contentHeight - screenHeight + header + footer;

    /* if total scrolled value is equal or greater
       than total height of content div (total scroll)
       and active page is the target page (pageX not any other page)
       call addMore() function */
    if (activePage[0].id == "pageX" && scrolled >= scrollEnd) {
        addMore();
    }
});

Demo ⁽¹⁾

⁽¹⁾ Tested on iPhone 5 Safari Mobile