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jQuery Lazy Loading - Problem with display:none

开发者 https://www.devze.com 2023-02-28 11:53 出处:网络
I want to display Lazy Loading in one of my websites, the problem is I have several images that must stay hidden until I need them (for example a warning sign used on a form - the validation process -

I want to display Lazy Loading in one of my websites, the problem is I have several images that must stay hidden until I need them (for example a warning sign used on a form - the validation process - the image becomes visible only when the field is filled incorrectly).

Is there a solution to modify Lazy Loading so it ignores all images containing the "display:none" attribute?

Thank you very much!

Plugin URL: http://www.appelsiini.net/projects/lazyload

Code used on the page:

<script src="js/jquery.lazyload.js />" type="text/javascript"></script>
<script type="text/javascript" charset="utf-8"> 
  $(function() {     
        if      
      $("img").lazyload({
         placeholder : "img/grey.gif",
         effect      : "fadeIn"
      });
  });
</script> 

And the plugin code (jquery.lazyload.js)

(function($) {
    $.fn.lazyload = function(options) {
        var settings = {
            threshold    : 0,
            failurelimit : 0,
            event        : "scroll",
            effect       : "show",
            container    : window
        };

        if(options) {
            $.extend(settings, options);
        }

        /* Fire one scroll event per scroll. Not one scroll event per image. */
        var elements = this;
        if ("scroll" == settings.event) {
            $(settings.container).bind("scroll", function(event) {

                var counter = 0;
                elements.each(function() {
                    if ($.abovethetop(this, settings) ||
                        $.leftofbegin(this, settings)) {
                            /* Nothing. */
                    } else if (!$.belowthefold(this, settings) &&
                        !$.rightoffold(this, settings)) {
                            $(this).trigger("appear");
                    } else {
                        if (counter++ > settings.failurelimit) {
                            return false;
                        }
                    }
                });
                /* Remove image from array so it is not looped next time. */
                var temp = $.grep(elements, function(element) {
                    return !element.loaded;
                });
                elements = $(temp);
            });
        }

        this.each(function() {
            var self = this;

            /* Save original only if it is not defined in HTML. */
            if (undefined == $(self).attr("original")) {
                $(self).attr("original", $(self).attr("src"));     
            }

            if ("scroll" != settings.event || 
                    undefined == $(self).attr("src") || 
                    settings.placeholder == $(self).attr("src") || 
                    ($.abovethetop(self, settings) ||
                     $.leftofbegin(self, settings) || 
                     $.belowthefold(self, settings) || 
                     $.rightoffold(self, settings) )) {

                if (settings.placeholder) {开发者_StackOverflow中文版
                    $(self).attr("src", settings.placeholder);      
                } else {
                    $(self).removeAttr("src");
                }
                self.loaded = false;
            } else {
                self.loaded = true;
            }

            /* When appear is triggered load original image. */
            $(self).one("appear", function() {
                if (!this.loaded) {
                    $("<img />")
                        .bind("load", function() {
                            $(self)
                                .hide()
                                .attr("src", $(self).attr("original"))
                                [settings.effect](settings.effectspeed);
                            self.loaded = true;
                        })
                        .attr("src", $(self).attr("original"));
                };
            });

            /* When wanted event is triggered load original image */
            /* by triggering appear.                              */
            if ("scroll" != settings.event) {
                $(self).bind(settings.event, function(event) {
                    if (!self.loaded) {
                        $(self).trigger("appear");
                    }
                });
            }
        });

        /* Force initial check if images should appear. */
        $(settings.container).trigger(settings.event);

        return this;

    };

    /* Convenience methods in jQuery namespace.           */
    /* Use as  $.belowthefold(element, {threshold : 100, container : window}) */

    $.belowthefold = function(element, settings) {
        if (settings.container === undefined || settings.container === window) {
            var fold = $(window).height() + $(window).scrollTop();
        } else {
            var fold = $(settings.container).offset().top + $(settings.container).height();
        }
        return fold <= $(element).offset().top - settings.threshold;
    };

    $.rightoffold = function(element, settings) {
        if (settings.container === undefined || settings.container === window) {
            var fold = $(window).width() + $(window).scrollLeft();
        } else {
            var fold = $(settings.container).offset().left + $(settings.container).width();
        }
        return fold <= $(element).offset().left - settings.threshold;
    };

    $.abovethetop = function(element, settings) {
        if (settings.container === undefined || settings.container === window) {
            var fold = $(window).scrollTop();
        } else {
            var fold = $(settings.container).offset().top;
        }
        return fold >= $(element).offset().top + settings.threshold  + $(element).height();
    };

    $.leftofbegin = function(element, settings) {
        if (settings.container === undefined || settings.container === window) {
            var fold = $(window).scrollLeft();
        } else {
            var fold = $(settings.container).offset().left;
        }
        return fold >= $(element).offset().left + settings.threshold + $(element).width();
    };
    /* Custom selectors for your convenience.   */
    /* Use as $("img:below-the-fold").something() */

    $.extend($.expr[':'], {
        "below-the-fold" : "$.belowthefold(a, {threshold : 0, container: window})",
        "above-the-fold" : "!$.belowthefold(a, {threshold : 0, container: window})",
        "right-of-fold"  : "$.rightoffold(a, {threshold : 0, container: window})",
        "left-of-fold"   : "!$.rightoffold(a, {threshold : 0, container: window})"
    });

})(jQuery);


Lazy Load is currently not usable. It does not work with the latest browsers as expected.

... from the url of your plugin
and if you still want to use that plugin, i think you can call

$("img:visible").lazyload({
     placeholder : "img/grey.gif",
     effect      : "fadeIn"
  });

hope that help...

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