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How to make Twitter Bootstrap menu dropdown on hover rather than click

I'd like to have my Bootstrap menu automatically drop down on hover, rather than having to click the menu title. I'd also like to lose the little arrows next to the menu titles.

There is a solution for that, so mikko's answer is correct but covered now with a plugin for specifically that situation. bootstrap-hover-dropdown
See my newly published proper plugin which prevents the issues of the below CSS and js solutions, and works fine on iOS and on modern desktop browsers with touch events. Even the aria attributes are working fine with that: github.com/istvan-ujjmeszaros/bootstrap-dropdown-hover
I made a pure CSS3 dropdown with a bootstrap navbar check it out on CodePen Pure CSS3 Dropdown
Think twice if you really need it? Bootstrap is using for adaptive sites. It means they will be used on devices with touch controls as well. That's why it is designed this way. There is no "hover" on touch screens.
Possible duplicate of Bootstrap Dropdown with Hover

T
Travis

To get the menu to automatically drop on hover then this can achieved using basic CSS. You need to work out the selector to the hidden menu option and then set it to display as block when the appropriate li tag is hovered over. Taking the example from the twitter bootstrap page, the selector would be as follows:

ul.nav li.dropdown:hover > ul.dropdown-menu {
    display: block;    
}

However, if you are using Bootstrap's responsive features, you will not want this functionality on a collapsed navbar (on smaller screens). To avoid this, wrap the code above in a media query:

@media (min-width: 979px) {
  ul.nav li.dropdown:hover > ul.dropdown-menu {
    display: block;
  }
}

To hide the arrow (caret) this is done in different ways depending on whether you are using Twitter Bootstrap version 2 and lower or version 3:

Bootstrap 3

To remove the caret in version 3 you just need to remove the HTML <b class="caret"></b> from the .dropdown-toggle anchor element:

<a class="dropdown-toggle" data-toggle="dropdown" href="#">
    Dropdown
    <b class="caret"></b>    <-- remove this line
</a>

Bootstrap 2 & lower

To remove the caret in version 2 you need a little more insight into CSS and I suggest looking at how the :after pseudo element works in more detail. To get you started on your way to understanding, to target and remove the arrows in the twitter bootstrap example, you would use the following CSS selector and code:

a.menu:after, .dropdown-toggle:after {
    content: none;
}

It will work in your favour if you look further into how these work and not just use the answers that I have given you.

Thanks to @CocaAkat for pointing out that we were missing the ">" child combinator to prevent sub menus being shown on the parent hover


Also had to add margin: 0;, otherwise the 1px margin above .dropdown-menu causes buggy behavior.
Simple solution, but the parent link is still not clickable. I'm using latest bootstrap with roots theme.
Note: Yes it does - this will work in any browser that twitter bootstrap supports. @GeorgeEdison This is basic CSS - what part would not be supported by IE8? If you are having problems, post a question, not misleading comments.
@MyHeadHurts: After some further research - turns out this was indeed a Bootstrap bug and it was only fixed five days ago.
@Krunal to be able to click the link, you must remove the data-toggle="dropdown" attribute.
P
Peter Mortensen

I created a pure on hover dropdown menu based on the latest (v2.0.2) Bootstrap framework that has support for multiple submenus and thought I'd post it for future users:

body { padding-top: 60px; padding-bottom: 40px; } .sidebar-nav { padding: 9px 0; } .dropdown-menu .sub-menu { left: 100%; position: absolute; top: 0; visibility: hidden; margin-top: -1px; } .dropdown-menu li:hover .sub-menu { visibility: visible; } .dropdown:hover .dropdown-menu { display: block; } .nav-tabs .dropdown-menu, .nav-pills .dropdown-menu, .navbar .dropdown-menu { margin-top: 0; } .navbar .sub-menu:before { border-bottom: 7px solid transparent; border-left: none; border-right: 7px solid rgba(0, 0, 0, 0.2); border-top: 7px solid transparent; left: -7px; top: 10px; } .navbar .sub-menu:after { border-top: 6px solid transparent; border-left: none; border-right: 6px solid #fff; border-bottom: 6px solid transparent; left: 10px; top: 11px; left: -6px; }


Demo


it's a design decision in bootstrap to do not open the dropdowns on hover event...
so good! I also removed class="dropdown-toggle" data-toggle="dropdown" so that only hovers, not click would trigger the menu. Note that when you're using responsive styles, the menus still get swept into the little button at top right, which is still triggered by a click. Big Thanks!
To avoid the auto drop down on smaller devices (such as phones) and aonly allow it as of a min-width of e.g. 768px do @media (min-width: 768px) {.dropdown-menu li:hover .sub-menu {visibility: visible;}} and @media (min-width: 768px) {.dropdown:hover .dropdown-menu {display: block;}}
Also to make link with children clickable, you have to remove the "data-toggle='dropdown'" on tag.
j
johannchopin

In addition to the answer from "My Head Hurts" (which was great):

ul.nav li.dropdown:hover ul.dropdown-menu{
    display: block;    
}

There are 2 lingering issues:

Clicking on the dropdown link will open the dropdown-menu. And it will stay open unless the user clicks somewhere else, or hovers back over it, creating an awkward UI. There is a 1px margin between the dropdown link, and dropdown-menu. This causes the dropdown-menu to become hidden if you move slowly between the dropdown and dropdown-menu.

The solution to (1) is removing the "class" and "data-toggle" elements from the nav link

<a href="#">
     Dropdown
     <b class="caret"></b>
</a>

This also gives you the ability to create a link to your parent page - which wasn't possible with the default implementation. You can just replace the "#" with whatever page you want to send the user.

The solution to (2) is removing the margin-top on the .dropdown-menu selector

.navbar .dropdown-menu {
    margin-top: 0px;
}

To fix the deliberate click, I just removed the data-toggle="dropdown" attribute, which seemed to work.
Solution (2) for nav-pill buttons: .nav-pills .dropdown-menu { margin-top: 0px; }
To fix the problem I noted above li.dropdown:hover > ul.dropdown-menu
removing "class" and "data-toggle" attributes from nav links make it stop working fine in mobile and tablets :(
If you removed the data-toggle="dropdown" attribute, you won't be able to expand the drop down menu using the keyboard. So it will not be 508 compliant. How can you disable the click but keep the keyboard functionality?
P
Peter Mortensen

I've used a bit of jQuery:

// Add hover effect to menus
jQuery('ul.nav li.dropdown').hover(function() {
  jQuery(this).find('.dropdown-menu').stop(true, true).delay(200).fadeIn();
}, function() {
  jQuery(this).find('.dropdown-menu').stop(true, true).delay(200).fadeOut();
});

Like this. Am using JQuery anyway with the Bootstrap stuff and still allows for the default 'click' functionality in touchscreen devices.
Used this. I like that it still allows the click functionality as well, for mobiles, but for desktops the hover is perfect.
I used this but also extended it to be useable for dropdowns that are not in a nav. I add class dropdown-hover to the btn-group div and used this jQuery finder $('ul.nav li.dropdown, .dropdown-hover').hover(function() {. Thanks!
Used this one, nice and small. The css version did not allow submenu to stay displayed, and 200ms was too quick so I changed it to $('ul.nav li.dropdown').hover(function() { $(this).find('.dropdown-menu').stop(true, true).delay(200).fadeIn(); }, function() { $(this).find('.dropdown-menu').stop(true, true).delay(200).fadeOut().hover(function() { $(this).stop(true, true); }); }); : When the submenu is hover stop fadeOut
@nuander, this was intended for Bootstrap V1/2 ::: So this solution is not relevant anymore :::
j
johannchopin

Simply customize your CSS style in three lines of code

.dropdown:hover .dropdown-menu {
   display: block;
}

G
GeoffCodesThings

There are a lot of really good solutions here. But I thought that I would go ahead and put mine in here as another alternative. It's just a simple jQuery snippet that does it the way bootstrap would if it supported hover for dropdowns instead of just click. I've only tested this with version 3 so I don't know if it would work with version 2. Save it as a snippet in your editor and have it at the stroke of a key.

<script>
    $(function() {
        $(".dropdown").hover(
            function(){ $(this).addClass('open') },
            function(){ $(this).removeClass('open') }
        );
    });
</script>

Basically, It's just saying when you hover on the dropdown class, it will add the open class to it. Then it just works. When you stop hovering on either the parent li with the dropdown class or the child ul/li's, it removes the open class. Obviously, this is only one of many solutions, and you can add to it to make it work on only specific instances of .dropdown. Or add a transition to either parent or child.


Great solution! I also removed data-toggle="dropdown" attribute from link in order to make top link clickable.
That's a good tip Sergey. I always make sure the top link goes nowhere so that it works on tablets and phones as well.
@Sergey I wouldn't recommend doing that. You would break the functionality for mobile users. They can't use the hover function to open a menu and need to be able to click it.
This looks really good. Any idea how to add a bit of animation using CSS transitions?
In Bootstrap 4 you can get the same result by finding a child element with the dropdown-menu class and using the show class toggle:function(){ $(this).find(".dropdown-menu").addClass('show') }, function(){ $(this).find(".dropdown-menu").removeClass('show') }
P
Peter Mortensen

If you have an element with a dropdown class like this (for example):

<ul class="list-unstyled list-inline">
    <li class="dropdown">
        <a data-toggle="dropdown" href="#"><i class="fa fa-bars"></i> Dropdown 1</a>
        <ul class="dropdown-menu">
            <li><a href="">Item 1</a></li>
            <li><a href="">Item 2</a></li>
            <li><a href="">Item 3</a></li>
            <li><a href="">Item 4</a></li>
            <li><a href="">Item 5</a></li>
        </ul>
    </li>
    <li class="dropdown">
        <a data-toggle="dropdown" href="#"><i class="fa fa-user"></i> Dropdown 2</a>
        <ul class="dropdown-menu">
            <li><a href="">Item A</a></li>
            <li><a href="">Item B</a></li>
            <li><a href="">Item C</a></li>
            <li><a href="">Item D</a></li>
            <li><a href="">Item E</a></li>
        </ul>
    </li>
</ul>

Then you can have the dropdown menu to be automatically drop down on hover over, rather than having to click its title, by using this snippet of jQuery code:

<script>
    $('.dropdown').hover(
        function() {
            $(this).find('.dropdown-menu').stop(true, true).delay(200).fadeIn();
        },
        function() {
            $(this).find('.dropdown-menu').stop(true, true).delay(200).fadeOut();
        }
    );

    $('.dropdown-menu').hover(
        function() {
            $(this).stop(true, true);
        },
        function() {
            $(this).stop(true, true).delay(200).fadeOut();
        }
    );
</script>

Here is a demo

This answer relied on @Michael answer, I have made some changes and added some additions to get the dropdown menu work properly


C
CWSpear

[Update] The plugin is on GitHub and I am working on some improvements (like use only with data-attributes (no JS necessary). I've leaving the code in below, but it's not the same as what's on GitHub.

I liked the purely CSS version, but it's nice to have a delay before it closes, as it's usually a better user experience (i.e. not punished for a mouse slip that goes 1 px outside the dropdown, etc), and as mentioned in the comments, there's that 1px of margin you have to deal with or sometimes the nav closes unexpectedly when you're moving to the dropdown from the original button, etc.

I created a quick little plugin that I've used on a couple sites and it's worked nicely. Each nav item is independently handled, so they have their own delay timers, etc.

JS

// outside the scope of the jQuery plugin to
// keep track of all dropdowns
var $allDropdowns = $();

// if instantlyCloseOthers is true, then it will instantly
// shut other nav items when a new one is hovered over
$.fn.dropdownHover = function(options) {

    // the element we really care about
    // is the dropdown-toggle's parent
    $allDropdowns = $allDropdowns.add(this.parent());

    return this.each(function() {
        var $this = $(this).parent(),
            defaults = {
                delay: 500,
                instantlyCloseOthers: true
            },
            data = {
                delay: $(this).data('delay'),
                instantlyCloseOthers: $(this).data('close-others')
            },
            options = $.extend(true, {}, defaults, options, data),
            timeout;

        $this.hover(function() {
            if(options.instantlyCloseOthers === true)
                $allDropdowns.removeClass('open');

            window.clearTimeout(timeout);
            $(this).addClass('open');
        }, function() {
            timeout = window.setTimeout(function() {
                $this.removeClass('open');
            }, options.delay);
        });
    });
};  

The delay parameter is pretty self explanatory, and the instantlyCloseOthers will instantly close all other dropdowns that are open when you hover over a new one.

Not pure CSS, but hopefully will help someone else at this late hour (i.e. this is an old thread).

If you want, you can see the different processes I went through (in a discussion on the #concrete5 IRC) to get it to work via the different steps in this gist: https://gist.github.com/3876924

The plugin pattern approach is much cleaner to support individual timers, etc.

See the blog post for more.


j
johannchopin

This worked for me:

.dropdown:hover .dropdown-menu {
    display: block;
}

With mobile however - it is strange.
The margin between menu and dropdown-menu makes this useless.
j
johannchopin

This is built into Bootstrap 3. Just add this to your CSS:

.dropdown:hover .dropdown-menu {
    display: block;
}

c
caarlos0

Even better with jQuery:

jQuery('ul.nav li.dropdown').hover(function() {
  jQuery(this).find('.dropdown-menu').stop(true, true).show();
  jQuery(this).addClass('open');
}, function() {
  jQuery(this).find('.dropdown-menu').stop(true, true).hide();
  jQuery(this).removeClass('open');
});

I changed your code to jQuery('ul.nav li.dropdown').hover(function() { jQuery(this).closest('.dropdown-menu').stop(true, true).show(); jQuery(this).addClass('open'); }, function() { jQuery(this).closest('.dropdown-menu').stop(true, true).hide(); jQuery(this).removeClass('open'); }); so the submenu won't be displayed on hover.
This code won't work anymore with the latest releases.
j
johannchopin

Just want to add, that if you have multiple dropdowns (as I do) you should write:

ul.nav li.dropdown:hover > ul.dropdown-menu {
    display: block;    
}

And it'll work properly.


My .dropdown-menu had margin: 2px 0 0; which meant a slow mouseEnter from above hid the menu prematurely. ul.dropdown-menu{ margin-top: 0; }
s
sdvnksv

You can use the default $().dropdown('toggle') method to toggle the dropdown menu on hover:

$(".nav .dropdown").hover(function() {
  $(this).find(".dropdown-toggle").dropdown("toggle");
});

P
Peter Mortensen

The best way of doing it is to just trigger Bootstrap's click event with a hover. This way, it should still remain touch device friendly.

$('.dropdown').hover(function(){ 
  $('.dropdown-toggle', this).trigger('click'); 
});

Unwanted result: mousein, click and mouseout will leave the menu open. This is not what I want...
Using this, It run the bootstrap function to open the dropdown, That function does many other things, like aria-expanded="true"
P
Peter Mortensen

In my opinion the best way is like this:

;(function($, window, undefined) {
    // Outside the scope of the jQuery plugin to
    // keep track of all dropdowns
    var $allDropdowns = $();

    // If instantlyCloseOthers is true, then it will instantly
    // shut other nav items when a new one is hovered over
    $.fn.dropdownHover = function(options) {

        // The element we really care about
        // is the dropdown-toggle's parent
        $allDropdowns = $allDropdowns.add(this.parent());

        return this.each(function() {
            var $this = $(this),
                $parent = $this.parent(),
                defaults = {
                    delay: 500,
                    instantlyCloseOthers: true
                },
                data = {
                    delay: $(this).data('delay'),
                    instantlyCloseOthers: $(this).data('close-others')
                },
                settings = $.extend(true, {}, defaults, options, data),
                timeout;

            $parent.hover(function(event) {

                // So a neighbor can't open the dropdown
                if(!$parent.hasClass('open') && !$this.is(event.target)) {
                    return true;
                }

                if(settings.instantlyCloseOthers === true)
                    $allDropdowns.removeClass('open');

                window.clearTimeout(timeout);
                $parent.addClass('open');
            }, function() {
                timeout = window.setTimeout(function() {
                    $parent.removeClass('open');
                }, settings.delay);
            });

            // This helps with button groups!
            $this.hover(function() {
                if(settings.instantlyCloseOthers === true)
                    $allDropdowns.removeClass('open');

                window.clearTimeout(timeout);
                $parent.addClass('open');
            });

            // Handle submenus
            $parent.find('.dropdown-submenu').each(function(){
                var $this = $(this);
                var subTimeout;
                $this.hover(function() {
                    window.clearTimeout(subTimeout);
                    $this.children('.dropdown-menu').show();

                    // Always close submenu siblings instantly
                    $this.siblings().children('.dropdown-menu').hide();
                }, function() {
                    var $submenu = $this.children('.dropdown-menu');
                    subTimeout = window.setTimeout(function() {
                        $submenu.hide();
                    }, settings.delay);
                });
            });
        });
    };

    $(document).ready(function() {
        // apply dropdownHover to all elements with the data-hover="dropdown" attribute
        $('[data-hover="dropdown"]').dropdownHover();
    });
})(jQuery, this);

Sample markup:

<li class="dropdown">
    <a href="#" class="dropdown-toggle" data-toggle="dropdown" data-hover="dropdown" data-delay="1000" data-close-others="false">
        Account <b class="caret"></b>
    </a>
    <ul class="dropdown-menu">
        <li><a tabindex="-1" href="#">My Account</a></li>
        <li class="divider"></li>
        <li><a tabindex="-1" href="#">Change Email</a></li>
        <li><a tabindex="-1" href="#">Change Password</a></li>
        <li class="divider"></li>
        <li><a tabindex="-1" href="#">Logout</a></li>
    </ul>
</li>

This is Cameron Spear's work, thought I'd give him the shoutout: cameronspear.com/blog/bootstrap-dropdown-on-hover-plugin
P
Peter Mortensen

I've managed it as follows:

$('ul.nav li.dropdown').hover(function(){
       $(this).children('ul.dropdown-menu').slideDown(); 
    }, function(){
       $(this).children('ul.dropdown-menu').slideUp(); 
});

I hope this helps someone...


P
Peter Mortensen

This is probably a stupid idea, but to just remove the arrow pointing down, you can delete the

<b class="caret"></b>

This does nothing for the up pointing one, though...


Z
Zub

I have published a proper plugin for the Bootstrap 3 dropdown hover functionality, in which you can even define what happens when clicking on the dropdown-toggle element (the click can be disabled):

https://github.com/istvan-ujjmeszaros/bootstrap-dropdown-hover

Why I made it when there are many solutions already?

I had issues with all the previously existing solutions. The simple CSS ones are not using the .open class on the .dropdown, so there will be no feedback on the drop-down toggle element when the drop-down is visible.

The js ones are interfering with clicking on .dropdown-toggle, so the dropdown shows up on hover, then hides it when clicking on an opened drop-down, and moving out the mouse will trigger the drop-down to show up again. Some of the js solutions are breaking iOS compatibility, some plugins are not working on modern desktop browsers which are supporting the touch events.

That's why I made the Bootstrap Dropdown Hover plugin which prevents all these issues by using only the standard Bootstrap javascript API, without any hack. Even the Aria attributes are working fine with this plugin.


What's your opinion about github.com/vadikom/smartmenus ? I cannot decide, both libraries seem to be really good.
Smartmenus looks really good, it may be better for menus. My plugin is just a small addition to the bootstrap dropdowns, it does no more than opening a dropdown on hover, while smartmenu supports submenus as well, and does some other fancy things.
Thanks. I see that smartmenu's code is very extensive and there's also a lot of CSS. So far I went with bootstrap-dropdown-hover, because it seems to do the job and more compact. I'm building a landing site with left side navbar.
J
Jack

This also can do that.


$('.dropdown').on('mouseover',function(){
    $(this).find('.dropdown-menu').show();
});
$('.dropdown').on('mouseleave',function(){
    $(this).find('.dropdown-menu').hide();
});

If the dropdown has a gap between the hovered element the drop down will immediately close as seen in this GIF

https://i.stack.imgur.com/rt10g.gif

To prevent this behaviour you can add a timeout to the events of 100 ms

let dropdownTimer;
$('.dropdown').on('mouseover', () => {
    clearTimeout(dropdownTimer)
    $(this).find('.dropdown-menu').show();
});
$('.dropdown').on('mouseleave', () =>{
    dropdownTimer = setTimeout(() => {
        $(this).find('.dropdown-menu').hide();
    }, 100)
});

https://i.stack.imgur.com/FMvUQ.gif


S
Sudharshan

Also added margin-top:0 to reset the bootstrap css margin for .dropdown-menu so the menu list dosen't dissapear when the user hovers slowly from drop down menu to the menu list.

ul.nav li.dropdown:hover > ul.dropdown-menu {
    display: block;    
}

.nav .dropdown-menu {
    margin-top: 0;
}

this is the correct answer, bootstrap is ready for hover on dropdown, if the mouse doesn't go outside of dropdown menu. Removing margin-top allow to go from link to menu without break and so without auto-close of the menu. And this solution allow to keep the correct behavior for touch devices
D
Drew

This works for Bootstrap V4

JS:

<script>
        $(function() {
            $('.dropdown-hover').hover(
                function() { $(this).addClass('show'); $(this).find('[data-toggle="dropdown"]').attr('aria-expanded', true); $(this).find('.dropdown-menu').addClass('show'); },
                function() { $(this).removeClass('show'); $(this).find('[data-toggle="dropdown"]').attr('aria-expanded',false); $(this).find('.dropdown-menu').removeClass('show'); }
            );
        });
    </script>

Vanilla Bootstrap 4 Dropdown HTML except for the addition of the dropdown-hover class:

<div class="dropdown dropdown-hover">
<button class="btn btn-text dropdown-toggle" type="button" id="dropdownMenuButton" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    ABOUT
</button>
<div class="dropdown-menu" aria-labelledby="dropdownMenuButton">
    <a class="dropdown-item" href="#">Action</a>
    <a class="dropdown-item" href="#">Another action</a>
    <a class="dropdown-item" href="#">Something else here</a>
</div>

If you don't want to selectively enable the hover feature by using the .dropdown-hover class then simply change the jquery selector from .dropdown-hover to .dropdown.


J
Jibato

Use this code to open the submenu on mousehover (desktop only):

$('ul.nav li.dropdown').hover(function () {
    if ($(window).width() > 767) {
        $(this).find('.dropdown-menu').show();
    }
}, function () {
    if ($(window).width() > 767) {
        $(this).find('.dropdown-menu').hide().css('display','');
    }
});

And if you want the first level menu to be clickable, even on mobile add this:

    $('.dropdown-toggle').click(function() {
    if ($(this).next('.dropdown-menu').is(':visible')) {
        window.location = $(this).attr('href');
    }
});

The submenu (dropdown-menu) will be opened with mousehover on desktop, and with click/touch on mobile and tablet. Once the submenu was open, a second click will let you open the link. Thanks to the if ($(window).width() > 767), the submenu will take the full screen width on mobile.


I'd like to use your code, but I'm having trouble getting it to work correctly. First, how to remove the hover() for mobile and only use that for desktop? When I use your code, and resize the window to mobile, I get both the hover() and click() functionality. But even more strange... is that this behavior will stop When I refresh the browser, ha! Could you show me how to fix this? I need desktop submenus to show on hover() and click()to show submenus on mobile Without having to refresh the browser even when resizing the window to work properly. I hope this is clear
Use this best method: @falter
N
Nikolay Kostov
$('.dropdown').hover(function(e){$(this).addClass('open')})

Please provide some details to your answer.
K
Kash

The very simple solution for version 2, only CSS. Keeps the same friendly functionality for mobile and tablet.

@media (min-width: 980px) {
    .dropdown:hover .dropdown-menu {
       display: block;
    }
}

This doesn't work great for some themes where there is a gap between the menu item and the dropdown. The menu will disappear when the mouse moves into this gap.
a
allochi

This will hide the up ones

.navbar .dropdown-menu:before {
   display:none;
}
.navbar .dropdown-menu:after {
   display:none;
}

J
Josh Crozier

This should hide the drop downs and their carets if they are smaller than a tablet.

@media (max-width: 768px) {
    .navbar ul.dropdown-menu, .navbar li.dropdown b.caret {
        display: none;
    }
}

Why would you want to hide it? Now the mobile users have no way to access the links that are in the submenu. It's better to turn the hover effect off on a mobile device and keep the dropdown menu intact. That way they can open it by clicking on it.
P
Peter Mortensen

The jQuery solution is good, but it will need to either deal with on click events (for mobile or tablet) as hover won't work properly... Could maybe do some window re-size detection?

Andres Ilich's answer seems to work well, but it should be wrapped in a media query:

@media (min-width: 980px) {

    .dropdown-menu .sub-menu {
        left: 100%;
        position: absolute;
        top: 0;
        visibility: hidden;
        margin-top: -1px;
    }

    .dropdown-menu li:hover .sub-menu {
        visibility: visible;
    }

    .dropdown:hover .dropdown-menu {
        display: block;
    }

    .nav-tabs .dropdown-menu, .nav-pills .dropdown-menu, .navbar .dropdown-menu {
        margin-top: 0;
    }

    .navbar .sub-menu:before {
        border-bottom: 7px solid transparent;
        border-left: none;
        border-right: 7px solid rgba(0, 0, 0, 0.2);
        border-top: 7px solid transparent;
        left: -7px;
        top: 10px;
    }
    .navbar .sub-menu:after {
        border-top: 6px solid transparent;
        border-left: none;
        border-right: 6px solid #fff;
        border-bottom: 6px solid transparent;
        left: 10px;
        top: 11px;
        left: -6px;
    }
}

P
Peter Mortensen

So you have this code:

<a class="dropdown-toggle" data-toggle="dropdown">Show menu</a>

<ul class="dropdown-menu" role="menu">
    <li>Link 1</li>
    <li>Link 2</li> 
    <li>Link 3</li>                                             
</ul>

Normally it works on a click event, and you want it work on a hover event. This is very simple, just use this JavaScript/jQuery code:

$(document).ready(function () {
    $('.dropdown-toggle').mouseover(function() {
        $('.dropdown-menu').show();
    })

    $('.dropdown-toggle').mouseout(function() {
        t = setTimeout(function() {
            $('.dropdown-menu').hide();
        }, 100);

        $('.dropdown-menu').on('mouseenter', function() {
            $('.dropdown-menu').show();
            clearTimeout(t);
        }).on('mouseleave', function() {
            $('.dropdown-menu').hide();
        })
    })
})

This works very well and here is the explanation: we have a button, and a menu. When we hover the button we display the menu, and when we mouseout of the button we hide the menu after 100 ms. If you wonder why I use that, is because you need time to drag the cursor from the button over the menu. When you are on the menu, the time is reset and you can stay there as many time as you want. When you exit the menu, we will hide the menu instantly without any timeout.

I've used this code in many projects, if you encounter any problem using it, feel free to ask me questions.


P
Peter Mortensen

For the caret... I haven't seen any one specifying simple CSS that totally blocks the caret.

Here you go:

.caret {
    display: none !important;
}

P
Peter Mortensen

Here is the JSFiddle -> https://jsfiddle.net/PRkonsult/mn31qf0p/1/

The JavaScript bit at the bottom is what does the actual magic.

HTML

<!--http://getbootstrap.com/components/#navbar-->
<div class="body-wrap">
  <div class="container">
    <nav class="navbar navbar-inverse" role="navigation">
      <div class="container-fluid">
        <!-- Brand and toggle get grouped for better mobile display -->
        <div class="navbar-header">
          <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1">
            <span class="sr-only">Toggle navigation</span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
          </button>
          <a class="navbar-brand" href="#">Brand</a>
        </div>

        <!-- Collect the nav links, forms, and other content for toggling -->
        <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
          <ul class="nav navbar-nav">
            <li class="active"><a href="#">Link</a></li>
            <li><a href="#">Link</a></li>
            <li class="dropdown">
              <a href="#" class="dropdown-toggle" data-toggle="dropdown">Dropdown <b class="caret"></b></a>
              <ul class="dropdown-menu">
                <li><a href="#">Action</a></li>
                <li><a href="#">Another action</a></li>
                <li><a href="#">Something else here</a></li>
                <li class="divider"></li>
                <li><a href="#">Separated link</a></li>
                <li class="divider"></li>
                <li><a href="#">One more separated link</a></li>
              </ul>
            </li>
          </ul>

          <ul class="nav navbar-nav navbar-right">
            <li><a href="#">Link</a></li>
            <li class="dropdown">
              <a href="#" class="dropdown-toggle" data-toggle="dropdown">Dropdown <b class="caret"></b></a>
              <ul class="dropdown-menu">
                <li><a href="#">Action</a></li>
                <li><a href="#">Another action</a></li>
                <li><a href="#">Something else here</a></li>
                <li class="divider"></li>
                <li><a href="#">Separated link</a></li>
              </ul>
            </li>
          </ul>
        </div>
        <!-- /.navbar-collapse -->
      </div>
      <!-- /.container-fluid -->
    </nav>
  </div>
</div>

CSS

/* Bootstrap dropdown hover menu */

body {
  font-family: 'PT Sans', sans-serif;
  font-size: 13px;
  font-weight: 400;
  color: #4f5d6e;
  position: relative;
  background: rgb(26, 49, 95);
  background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, rgba(26, 49, 95, 1)), color-stop(10%, rgba(26, 49, 95, 1)), color-stop(24%, rgba(29, 108, 141, 1)), color-stop(37%, rgba(41, 136, 151, 1)), color-stop(77%, rgba(39, 45, 100, 1)), color-stop(90%, rgba(26, 49, 95, 1)), color-stop(100%, rgba(26, 49, 95, 1)));
  filter: progid: DXImageTransform.Microsoft.gradient(startColorstr='#1a315f', endColorstr='#1a315f', GradientType=0);
}

.body-wrap {
  min-height: 700px;
}

.body-wrap {
  position: relative;
  z-index: 0;
}

.body-wrap: before,
.body-wrap: after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  z-index: -1;
  height: 260px;
  background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, rgba(26, 49, 95, 1)), color-stop(100%, rgba(26, 49, 95, 0)));
  background: linear-gradient(to bottom, rgba(26, 49, 95, 1) 0%, rgba(26, 49, 95, 0) 100%);
  filter: progid: DXImageTransform.Microsoft.gradient(startColorstr='#1a315f', endColorstr='#001a315f', GradientType=0);
}

.body-wrap:after {
  top: auto;
  bottom: 0;
  background: linear-gradient(to bottom, rgba(26, 49, 95, 0) 0%, rgba(26, 49, 95, 1) 100%);
  filter: progid: DXImageTransform.Microsoft.gradient(startColorstr='#001a315f', endColorstr='#1a315f', GradientType=0);
}

nav {
  margin-top: 60px;
  box-shadow: 5px 4px 5px #000;
}

Then the important bit of JavaScript code:

$('ul.nav li.dropdown').hover(function() {
  $(this).find('.dropdown-menu').stop(true, true).delay(200).fadeIn(500);
}, function() {
  $(this).find('.dropdown-menu').stop(true, true).delay(200).fadeOut(500);
});