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javascript - jQuery Lazy Loading - Problem with display:none - Stack Overflow

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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 bees 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:

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) {
                    $(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);

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 bees 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/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) {
                    $(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);
Share Improve this question asked Apr 23, 2011 at 11:46 Adrian M.Adrian M. 7,46315 gold badges48 silver badges54 bronze badges
Add a ment  | 

1 Answer 1

Reset to default 4

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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