当用户滚动到页面末尾时，使用jQuery .load（）

Question

I am using jQuery load() to load more content when the user scrolls to bottom of page. Here is my script.

$(window).scroll(function () {
    if ($(window).scrollTop() >= $(document).height() - $(window).height()) {
        var visible_posts = $('.post').length - 1;
        $(".posts").append('<div class="more-content-'+ visible_posts + '"></div>');
        $(".more-content-" + visible_posts).html('<div class="loading"><img src="/img/loading.gif" alt="" />');
        $(".more-content-" + visible_posts).load('<?php bloginfo('template_directory'); ?>/ajax/get_posts.php?offset=' + visible_posts);
    }
});

The problem is this creates weird behaviour and many loading gifs if scrolling of user is too quick.. I think because it append the div with loading div every and each time condition is met even before load is done.

Question is:

Is there A way to Stop the script after the first execution .. Run load() ... then re-enable the function ? Something similar to unbind click when you want to disable too fast clicks.

Any idea?

Answer 1

How about re-enable the function after load is complete?

var canLoad = true;
$(window).scroll(function () {
    if ($(window).scrollTop() >= $(document).height() - $(window).height() && canLoad) {
        canLoad = false;
        // other stuff
        $(".more-content").load('stuff', function() {
           // re-enable scroll function
           canLoad = true;
        });
    }
});

Answer 2

Set a flag once you start loading the new page, and unset it once the page has been updated..

var loadingMore = false;
$(window).scroll(function () {
    if ( !loadingMore && 
         $(window).scrollTop() >= $(document).height() - $(window).height()) {

        loadingMore = true;

        var visible_posts = $('.post').length - 1;
        $(".posts").append('<div class="more-content-'+ visible_posts + '"></div>');
        $(".more-content-" + visible_posts).html('<div class="loading"><img src="/img/loading.gif" alt="" />');
        $(".more-content-" + visible_posts)
             .load('<?php bloginfo('template_directory'); ?>/ajax/get_posts.php?offset=' + visible_posts, 
                   function(){loadingMore = false;}
                  );
    }
});

It is important to note, that it is not just the div that appears multiple times, you are actually making multiple AJAX requests..

Answer 3

try this

var flag = true;
$(window).scroll(function () {
    if ($(window).scrollTop() >= $(document).height() - $(window).height()) {
        if(flag){
           flag = false;
           var visible_posts = $('.post').length - 1;
           $(".posts").append('<div class="more-content-'+ visible_posts + '"></div>');
           $(".more-content-" + visible_posts).html('<div class="loading"><img src="/img/loading.gif" alt="" />');
           $(".more-content-" + visible_posts).load('<?php bloginfo('template_directory'); ?>/ajax/get_posts.php?offset=' + visible_posts, function(){ 
           flag = true
          });
       }
    }
});

Answer 4

This should work, I've also added comments to help you:

$(window).scroll(function () {
  var bload = 1; // Add a boolean var
    if ($(window).scrollTop() >= $(document).height() - $(window).height() && bload) {
      // Check in the condition to see if we load
      bload = 0; // Set the boolean to false or zero, so that we don't load anything else until the var is true again
        var visible_posts = $('.post').length - 1;
        $(".posts").append('<div class="more-content-'+ visible_posts + '"></div>');
        $(".more-content-" + visible_posts).html('<div class="loading"><img src="/img/loading.gif" alt="" />');
        $(".more-content-" + visible_posts).load('<?php bloginfo('template_directory'); ?>/ajax/get_posts.php?offset=' + visible_posts, function () {
          bload = 1; // This gets fired when the load is done, so we can load again (we set the bool to true)
        });
    }
});