Bootstrap: How to collapse navbar earlier

问题

I want to collapse my navbar in earlier resolution than 768px, for example 992px, how would I do that? thanks! (I know I can customize it on the bootstrap page, but I don't want to start my project over again with new bootstrap.css file)

回答1:

If you don't want to manipulate Bootstrap by using Less/Sass (maybe because you want to load it via a CDN), this is what did the trick for me:

@media (min-width: 768px) and (max-width: 991px) {
    .navbar-collapse.collapse {
        display: none !important;
    }
    .navbar-collapse.collapse.in {
        display: block !important;
    }
    .navbar-header .collapse, .navbar-toggle {
        display:block !important;
    }
    .navbar-header {
        float:none;
    }
}

Demo: https://jsfiddle.net/0pmy8usr/

Add this in a separate CSS file and include it after bootstrap.css

UPDATE for Bootstrap 4:

@media(max-width:900px) {
  .navbar .navbar-brand {float:none;display: inline-block;}
  .navbar .navbar-nav>.nav-item { float: none; margin-left: .1rem;}
  .navbar .navbar-nav {float:none !important;}
  .nav-item{width:100%;text-align:left;} 
  .navbar-toggler {display: block !important;}
  .navbar-toggleable-sm.collapse {display:none !important}
  .navbar-toggleable-sm.collapse.in {display:block !important}
}

Demo: https://jsfiddle.net/mkvhbgnp/3/

回答2:

In variables.less, change

@grid-float-breakpoint:   @screen-sm-min

@grid-float-breakpoint: @screen-md-min;

回答3:

If you need to collapse your navbar in earlier resolution than 768px so you will need to use @media min-width and max-width, and you don't need to start new project for doing that simply create new .css file ( example: custom.css) and inset it under your main bootstrap.css to override its values. and write this code inside it :

CODE:

@media (min-width: 992px) {
   .collapse {
       display: none !important;
   }
}

Also, you can have a look at this post: change bootstrap navbar collapse.

I hope this will give you the solution.

回答4:

You can also override the bootstrap classes that close the gap. Bellow is the working code that overrides basic navbars with dropdown menus. Not all classes are overriden bellow, so depending on what you are using, you may need to override other classes.

    @media (min-width: 768px) and (max-width: 991px) {
        .navbar-nav .open .dropdown-menu {
            position: static;
            float: none;
            width: auto;
            margin-top: 0;
            background-color: transparent;
            border: 0;
            -webkit-box-shadow: none;
            box-shadow: none;
        }
        .navbar-nav .open .dropdown-menu > li > a {
            line-height: 20px;
        }
        .navbar-nav .open .dropdown-menu > li > a,
        .navbar-nav .open .dropdown-menu .dropdown-header {
            padding: 5px 15px 5px 25px;
        }
        .dropdown-menu > li > a {
            display: block;
            padding: 3px 20px;
            clear: both;
            font-weight: normal;
            line-height: 1.42857143;
            color: #333;
            white-space: nowrap;
        }
        .navbar-header {
            float: none;
        }
        .navbar-toggle {
            display: block;
        }
        .navbar-collapse {
            border-top: 1px solid transparent;
            box-shadow: inset 0 1px 0 rgba(255,255,255,0.1);
        }
        .navbar-collapse.collapse {
            display: none!important;
        }
        .navbar-nav {
            float: none!important;
            /*margin: 7.5px -15px;*/
            margin: 7.5px 50px 7.5px -15px
        }
        .navbar-nav>li {
            float: none;
        }
        .navbar-nav>li>a {
            padding-top: 10px;
            padding-bottom: 10px;
        }
        .navbar-text {
            float: none;
            margin: 15px 0;
        }
        /* since 3.1.0 */
        .navbar-collapse.collapse.in { 
            display: block!important;
        }
        .collapsing {
            overflow: hidden!important;
        }
    }

click here for the live demo code

回答5:

I would suggest bringing in bootstrap into your project in lieu of a CDN and simply look for the media query that looks like this:

@media (min-width: 768px) {
  .navbar-expand-md {
    -ms-flex-flow: row nowrap;
    flex-flow: row nowrap; //...etc.

And change it to:

@media (min-width: 900px) {
  .navbar-expand-md {
    -ms-flex-flow: row nowrap;
    flex-flow: row nowrap; // ...etc.

Or if you are using a CDN, create an override to that specific media query.

来源：https://stackoverflow.com/questions/21076922/bootstrap-how-to-collapse-navbar-earlier

标签

css

twitter-bootstrap

navbar

collapse