jQuery

Create a Sometimes position:fixed Top Menu jQuery

After reading Ben Nadel’s post (www.bennadel.com/blog/1810-Creating-A-Sometimes-Fixed-Position-Element-With-jQuery.htm) I decided that I wanted to implement his first example into my site. Only problem is, I didn’t want to write it out every time I wanted to call a new “sometimes-fixed-position-element” so I decided to make a jQuery plugin called “stickytoolbar” (Yup!).

/**
 * @author Some guy in the back alley
 * @licence WTF? Like I care
 *
 * This plugin is basically designed to allow some one to widgetise the handling of sticky toolbars from the example on
 * http://www.bennadel.com/blog/1810-Creating-A-Sometimes-Fixed-Position-Element-With-jQuery.htm
 *
 * This plugin is very basic and does nothing special tbh.
 *
 */
(function($){
    $.fn.stickytoolbar = function (options) {

        $(this).addClass(options.onStaticClass).data('options', $.extend({
            'onStaticClass': '',
            'onFixedClass': ''
        }, options));

        $(window).bind(
            'scroll resize', function () {
                $('.stickytoolbar-placeholder').each(function () {

                    var options = $(this).data().options,

                        // Get the current offset of the placeholder.
                        // Since the message might be in fixed
                        // position, it is the plcaeholder that will
                        // give us reliable offsets.
                        placeholderTop = $(this).offset().top,

                        // Gets the message element so it can be used
                        bar = $(this).find('.stickytoolbar-bar'),

                        // Get the current scroll of the window.
                        viewTop = $(window).scrollTop();

                    // Check to see if the view had scroll down
                    // past the top of the placeholder AND that
                    // the message is not yet fixed.
                    if ((viewTop > placeholderTop) && !bar.hasClass('stickytoolbar-fixed')) {

                        // The message needs to be fixed. Before
                        // we change its positon, we need to re-
                        // adjust the placeholder height to keep
                        // the same space as the message.
                        //
                        // NOTE: All we're doing here is going
                        // from auto height to explicit height.
                        $(this).height($(this).height());

                        // Make the message fixed.
                        bar.addClass('stickytoolbar-fixed')
                            .css({
                                left: $(this).offset().left + 'px',
                                top: '0px',
                                position: 'fixed',
                                width: $(this).width() + 'px'
                            })
                            .removeClass(options.onStaticClass)
                            .addClass(options.onFixedClass);

                        // Check to see if the view has scroll back up
                        // above the message AND that the message is
                        // currently fixed.
                    } else if ((viewTop <= placeholderTop) && bar.hasClass('stickytoolbar-fixed')) {

                        // Make the placeholder height auto again.
                        $(this).css({'height': 'auto', 'width': 'auto'});

                        // Remove the fixed position class on the
                        // message. This will pop it back into its
                        // static position.
                        bar.removeClass('stickytoolbar-fixed')
                            .css({left: 'auto', top: 'auto', position: 'static', width: 'auto'})
                            .removeClass(options.onFixedClass)
                            .addClass(options.onStaticClass);

                    }
                });
            }
        );
    };
})(jQuery);

You can use this plugin like so (as an example I have also placed in a setting param):

<script>
    $('.toolbar').stickytoolbar({ onStaticClass: 'sticktoolbar-static' });
</script>

<div class="stickytoolbar-placeholder toolbar">
    <div class="stickytoolbar-bar"></div>
</div>
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