Javascript Fixed Navigation Issue

Question

I'd like to put a fixed navigation on a custom XenForo style, but I've a problem: http://screencast.com/t/ttdpFz4DtQ6

The navigation template:

<xen:edithint template="navigation.css" />

<xen:if is="@fixedNavigation">

<div class="fixedNavigationWrapper">

</xen:if>

<div class="navigationHelper"></div>

<div id="navigation" class="pageWidth {xen:if $canSearch, withSearch}">
    <div class="pageContent">
        <nav>

<div class="navTabs">
    <ul class="publicTabs">

        <!-- home -->
        <xen:if is="{$showHomeLink}">
            <li class="navTab home PopupClosed"><a href="{$homeLink}" class="navLink">{xen:phrase home}</a></li>
        </xen:if>


        <!-- extra tabs: home -->
        <xen:if is="{$extraTabs.home}">
        <xen:foreach loop="$extraTabs.home" key="$extraTabId" value="$extraTab">
            <xen:if is="{$extraTab.linksTemplate}">
                <li class="navTab {$extraTabId} {xen:if $extraTab.selected, 'selected', 'Popup PopupControl PopupClosed'}">

                <a href="{$extraTab.href}" class="navLink">{$extraTab.title}<xen:if is="{$extraTab.counter}"><strong class="itemCount"><span class="Total">{$extraTab.counter}</span><span class="arrow"></span></strong></xen:if></a>
                <a href="{$extraTab.href}" class="SplitCtrl" rel="Menu"></a>

                <div class="{xen:if {$extraTab.selected}, 'tabLinks', 'Menu JsOnly tabMenu'} {$extraTabId}TabLinks">
                    <div class="primaryContent menuHeader">
                        <h3>{$extraTab.title}</h3>
                        <div class="muted">{xen:phrase quick_links}</div>
                    </div>
                    {xen:raw $extraTab.linksTemplate}
                </div>
            </li>
            <xen:else />
                <li class="navTab {$extraTabId} {xen:if $extraTab.selected, 'selected', 'PopupClosed'}">
                    <a href="{$extraTab.href}" class="navLink">{$extraTab.title}<xen:if is="{$extraTab.counter}"><strong class="itemCount"><span class="Total">{$extraTab.counter}</span><span class="arrow"></span></strong></xen:if></a>
                    <xen:if is="{$extraTab.selected}"><div class="tabLinks"></div></xen:if>
                </li>
            </xen:if>
        </xen:foreach>
        </xen:if>


        <!-- forums -->
        <xen:if is="{$tabs.forums}">
            <li class="navTab forums {xen:if $tabs.forums.selected, 'selected', 'Popup PopupControl PopupClosed'}">

                <a href="{$tabs.forums.href}" class="navLink NoPopupGadget" rel="Menu">{$tabs.forums.title}</a>

                <div class="{xen:if {$tabs.forums.selected}, 'tabLinks', 'Menu JsOnly tabMenu'} forumsTabLinks">
                    <div class="primaryContent menuHeader">
                        <h3>{$tabs.forums.title}</h3>
                        <div class="muted">{xen:phrase quick_links}</div>
                    </div>
                    <ul class="secondaryContent blockLinksList">
                    <xen:hook name="navigation_tabs_forums">
                        <xen:if is="{$visitor.user_id}"><li><a href="{xen:link 'forums/-/mark-read', $forum, 'date={$serverTime}'}" class="OverlayTrigger">{xen:phrase mark_forums_read}</a></li></xen:if>
                        <xen:if is="{$canSearch}"><li><a href="{xen:link search, '', 'type=post'}">{xen:phrase search_forums}</a></li></xen:if>
                        <xen:if is="{$visitor.user_id}">
                            <li><a href="{xen:link 'watched/forums'}">{xen:phrase watched_forums}</a></li>
                            <li><a href="{xen:link 'watched/threads'}">{xen:phrase watched_threads}</a></li>
                        </xen:if>
                        <li><a href="{xen:link 'find-new/posts'}" rel="nofollow">{xen:if $visitor.user_id, {xen:phrase new_posts}, {xen:phrase recent_posts}}</a></li>
                    </xen:hook>
                    </ul>
                </div>
            </li>
        </xen:if>


        <!-- extra tabs: middle -->
        <xen:if is="{$extraTabs.middle}">
        <xen:foreach loop="$extraTabs.middle" key="$extraTabId" value="$extraTab">
            <xen:if is="{$extraTab.linksTemplate}">
                <li class="navTab {$extraTabId} {xen:if $extraTab.selected, 'selected', 'Popup PopupControl PopupClosed'}">

                <a href="{$extraTab.href}" class="navLink">{$extraTab.title}<xen:if is="{$extraTab.counter}"><strong class="itemCount"><span class="Total">{$extraTab.counter}</span><span class="arrow"></span></strong></xen:if></a>
                <a href="{$extraTab.href}" class="SplitCtrl" rel="Menu"></a>

                <div class="{xen:if {$extraTab.selected}, 'tabLinks', 'Menu JsOnly tabMenu'} {$extraTabId}TabLinks">
                    <div class="primaryContent menuHeader">
                        <h3>{$extraTab.title}</h3>
                        <div class="muted">{xen:phrase quick_links}</div>
                    </div>
                    {xen:raw $extraTab.linksTemplate}
                </div>
            </li>
            <xen:else />
                <li class="navTab {$extraTabId} {xen:if $extraTab.selected, 'selected', 'PopupClosed'}">
                    <a href="{$extraTab.href}" class="navLink">{$extraTab.title}<xen:if is="{$extraTab.counter}"><strong class="itemCount"><span class="Total">{$extraTab.counter}</span><span class="arrow"></span></strong></xen:if></a>
                    <xen:if is="{$extraTab.selected}"><div class="tabLinks"></div></xen:if>
                </li>
            </xen:if>
        </xen:foreach>
        </xen:if>


        <!-- members -->
        <xen:if is="{$tabs.members}">
            <li class="navTab members {xen:if $tabs.members.selected, 'selected', 'Popup PopupControl PopupClosed'}">

                <a href="{$tabs.members.href}" class="navLink NoPopupGadget" rel="Menu">{$tabs.members.title}</a>

                <div class="{xen:if {$tabs.members.selected}, 'tabLinks', 'Menu JsOnly tabMenu'} membersTabLinks">
                    <div class="primaryContent menuHeader">
                        <h3>{$tabs.members.title}</h3>
                        <div class="muted">{xen:phrase quick_links}</div>
                    </div>
                    <ul class="secondaryContent blockLinksList">
                    <xen:hook name="navigation_tabs_members">
                        <li><a href="{xen:link members}">{xen:phrase notable_members}</a></li>
                        <xen:if is="{$xenOptions.enableMemberList}"><li><a href="{xen:link members/list}">{xen:phrase registered_members}</a></li></xen:if>
                        <li><a href="{xen:link online}">{xen:phrase current_visitors}</a></li>
                        <xen:if is="{$xenOptions.enableNewsFeed}"><li><a href="{xen:link recent-activity}">{xen:phrase recent_activity}</a></li></xen:if>
                        <xen:if is="{$canViewProfilePosts}"><li><a href="{xen:link find-new/profile-posts}">{xen:phrase new_profile_posts}</a></li></xen:if>
                    </xen:hook>
                    </ul>
                </div>
            </li>
        </xen:if>

        <xen:if is="@helpNavigationTab">
        <!-- help -->
        <xen:if is="{$tabs.help}">
            <li class="navTab help <xen:if is="{$controllerName} == 'XenForo_ControllerPublic_Help'">selected<xen:else />Popup PopupControl PopupClosed</xen:if>">

                <a href="{$tabs.help.href}" class="navLink NoPopupGadget" rel="Menu">{$tabs.help.title}</a>

                <div class="<xen:if is="{$controllerName} == 'XenForo_ControllerPublic_Help'">tabLinks<xen:else />Menu JsOnly tabMenu</xen:if>">
                    <div class="primaryContent menuHeader">
                        <h3>{$tabs.help.title}</h3>
                        <div class="muted">{xen:phrase quick_links}</div>
                    </div>
                    <ul class="secondaryContent blockLinksList">
                    <xen:hook name="navigation_tabs_help">
                        <li><a href="{xen:link help/smilies}">{xen:phrase smilies}</a></li>
                        <!-- <li><a href="{xen:link help/bb-codes}">{xen:phrase bb_codes}</a></li> -->
                                    <li><a href="{xen:link help/trophies}">{xen:phrase trophies}</a></li>
                                    <li><a href="{xen:link help/cookies}">{xen:phrase cookie_usage}</a></li>
                        <xen:if is="{$tosUrl}">
                                    <li><a href="{$tosUrl}">{xen:phrase terms_and_rules}</a></li>
                                    </xen:if>
                            </xen:hook>
                    </ul>
                </div>
            </li>
        </xen:if>

        </xen:if>       

        <!-- extra tabs: end -->
        <xen:if is="{$extraTabs.end}">
        <xen:foreach loop="$extraTabs.end" key="$extraTabId" value="$extraTab">
            <xen:if is="{$extraTab.linksTemplate}">
                <li class="navTab {$extraTabId} {xen:if $extraTab.selected, 'selected', 'Popup PopupControl PopupClosed'}">

                <a href="{$extraTab.href}" class="navLink">{$extraTab.title}<xen:if is="{$extraTab.counter}"><strong class="itemCount"><span class="Total">{$extraTab.counter}</span><span class="arrow"></span></strong></xen:if></a>
                <a href="{$extraTab.href}" class="SplitCtrl" rel="Menu"></a>

                <div class="{xen:if {$extraTab.selected}, 'tabLinks', 'Menu JsOnly tabMenu'} {$extraTabId}TabLinks">
                    <div class="primaryContent menuHeader">
                        <h3>{$extraTab.title}</h3>
                        <div class="muted">{xen:phrase quick_links}</div>
                    </div>
                    {xen:raw $extraTab.linksTemplate}
                </div>
            </li>
            <xen:else />
                <li class="navTab {$extraTabId} {xen:if $extraTab.selected, 'selected', 'PopupClosed'}">
                    <a href="{$extraTab.href}" class="navLink">{$extraTab.title}<xen:if is="{$extraTab.counter}"><strong class="itemCount"><span class="Total">{$extraTab.counter}</span><span class="arrow"></span></strong></xen:if></a>
                    <xen:if is="{$extraTab.selected}"><div class="tabLinks"></div></xen:if>
                </li>
            </xen:if>
        </xen:foreach>
        </xen:if>

        <!-- responsive popup -->
        <li class="navTab navigationHiddenTabs Popup PopupControl PopupClosed" style="display:none">    

            <a rel="Menu" class="navLink NoPopupGadget"><span class="menuIcon">{xen:phrase menu}</span></a>

            <div class="Menu JsOnly blockLinksList primaryContent" id="NavigationHiddenMenu"></div>
        </li>


        <!-- no selection -->
        <xen:if is="!{$selectedTab}">
            <li class="navTab selected"><div class="tabLinks"></div></li>
        </xen:if>

    </ul>

    <xen:if is="{$visitor.user_id}"><xen:include template="navigation_visitor_tab" /></xen:if>
</div>

<span class="helper"></span>

        </nav>  
    </div>
</div>

<xen:if is="@fixedNavigation">
</div>
</xen:if>

The js code:

<xen:if is="@fixedNavigation">
<script type="text/javascript">
$(window).scroll( function() {
    if ($(window).scrollTop() > $('.fixedNavigationWrapper').offset().top)
        $('.fixedNavigationWrapper').addClass('fixed');
    else
        $('.fixedNavigationWrapper').removeClass('fixed');
} );
</script>
</xen:if>

CSS:

.fixedNavigationWrapper.fixed
{
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100000;
}

When I scroll the page, the navigation is not visible and it disappears. I'd like to know where the error is coming from.

Answer 1

Try adding a check to see if the fixed class has already been set. Setting it every time the page scroll event is fired will probably cause flicker and may even make the element disappear:

if(!$(".fixedNavigationWrapper").hasClass("fixed")) {
    $('.fixedNavigationWrapper').addClass('fixed');
}