Detect end of horizontal scrolling div with jQuery

问题:

So, I've got some data tossed in a div. It's split up into chunks by date. It scrolls horizontally with the use of jQuery and the mousewheel plugin.

I need to fire an event when the div has reached it's terminal point (farthest left, farthest right). I think that it is possible with the way it is currently implemented to calculate when you cannot scroll any further by detecting the data fetched in the mousewheel plugin. I just need a nudge in the right direction. Here's the code that does the horizontal scrolling for me:

$(document).ready(function () {        
    $('#timeline').mousedown(function (event) {
        $(this)
            .data('down', true)
            .data('x', event.clientX)
            .data('scrollLeft', this.scrollLeft);
        return false;
    }).mouseup(function (event) {
        $(this).data('down', false);
    }).mousemove(function (event) {
        if ($(this).data('down') == true) {
            this.scrollLeft = $(this).data('scrollLeft') + $(this).data('x') - event.clientX;
        }
    }).mousewheel(function (event, delta) {
        this.scrollLeft -= (delta * 30);
    }).css({
        'overflow' : 'hidden',
        'cursor' : '-moz-grab'
    });
});

Can anybody give me some direction? Thanks!

回答1:

Hey, I've prepared a page for you with the implementation. You can see how to detect the end of scrolling area with jQuery.

For the document as a whole you must detect in javascript whether .scrollTop has become equal to .scrollHeight. With jQuery it would be to detect:

if ( $(document).scrollTop() == ( $(document).height() - $(window).height() ) {
  // Do something here ...
}

The same is done for width. Have a look on example with div here.

回答2:

Here is the code that you want. It's proved that works on IE, Safari, Chrome, Firefox, etc.

Here is the HTML part.

    <div id="slide-wrap" style="width:1000px; height:200px; overflow:hidden; padding:0 auto;">
        <div id="inner-wrap" style="float:left;">
            <!-- 'Put Inline contains here like below.' -->
            <div class='containBox' style="width:250px; height:100%; float:left; display:inline-block;"></div>
            <!--  ...  -->
            <div class='containBox' style="width:250px; height:100%; float:left; display:inline-block;"></div>
            <!-- 'Put Inline contains here like above.' -->
        </div>
        <div style="display: block; width:40px; height:60px; position: absolute; margin-left:0px;   margin-top:40px">
            <img id='scroll_L_Arrow' src='../assets/img/l-arrow.png' onclick="scrollThumb('Go_L')"/>
        </div>
        <div style="display: block; width:40px; height:60px; position: absolute; margin-left:960px; margin-top:40px">
            <img id='scroll_R_Arrow' src='../assets/img/r-arrow.png' onclick="scrollThumb('Go_R')"/>
        </div>
    </div>

Here is jQuery part in JavaScript functions.

    function scrollArrowShow() {
        var maxScroll = ($('#inner-wrap').width() - $('#slide-wrap').scrollLeft()) - $('#slide-wrap').width();
        if ( 0 == $('#slide-wrap').scrollLeft()) {
            $('#scroll_L_Arrow').css({visibility: 'hidden'});
        }else{
            $('#scroll_L_Arrow').css({visibility: 'visible'});
        }
        if ( 0 == maxScroll) {
            $('#scroll_R_Arrow').css({visibility: 'hidden'});
        }else{
            $('#scroll_R_Arrow').css({visibility: 'visible'});
        }
    }

       function scrollThumb(direction) {
        if (direction=='Go_L') {
            $('#slide-wrap').animate({
                scrollLeft: "-=" + 250 + "px"
            }, function(){
                // createCookie('scrollPos', $('#slide-wrap').scrollLeft());
                scrollArrowShow();
            });
        }else
        if (direction=='Go_R') {
            $('#slide-wrap').animate({
                scrollLeft: "+=" + 250 + "px"
            }, function(){
                // createCookie('scrollPos', $('#slide-wrap').scrollLeft());
                scrollArrowShow();
            });
        }
       }

回答3:

$('.div-with-scrollbar').scroll(function () {
  var $elem = $('.div-with-scrollbar');
  var newScrollLeft = $elem.scrollLeft(),
      width = $elem.width(),
      scrollWidth = $elem.get(0).scrollWidth;
  var offset = 0;
  if (scrollWidth - newScrollLeft - width === offset) {
    alert('right end')
  }
  if (newScrollLeft === 0) {
    alert('left')
  }
});