Question

我想在悬停时制作引导菜单下拉菜单，而不是点击一些很酷的动画。所以我编写了以下代码，它完全适用于Google Chrome和Internet Explorer。但它不适用于Firefox。

if (matchMedia) {
    var mq = window.matchMedia("(min-width: 768px)");
    mq.addListener(WidthChange);
    WidthChange(mq);
}

function WidthChange(mq) {
    if (mq.matches) {
        $(function () {
            $('li.dropdown').hover(function () {
                $(this).addClass('open');
            }, function () {
                $(this).removeClass('open');
            });
        });
    }
}

@media (min-width: 768px) {
    ul.dropdown-menu {
        opacity: 0;
        transition: all 0.2s linear;
        -webkit-transition: all 0.2s linear;
        transform: translate(0, 10px);
        -webkit-transform: translate(0, 10px);
    }
    li.open > ul.dropdown-menu {
        -webkit-transform: translate(0, 0);
        transform: translate(0, 0);
        opacity: 1;
    }
    li.dropdown:hover ul.dropdown-menu {
        display: block !important;
    }
}

<link href="https://jsfiddle.net/0jbxzh5w/1/vsn4ik.github.io/bootstrap-submenu/dist/css/bootstrap-submenu.css" rel="stylesheet"/>
<script src="https://github.com/vsn4ik/bootstrap-submenu/blob/master/js/bootstrap-submenu.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<nav class="navbar navbar-default">
    <div class="navbar-header">
        <button class="navbar-toggle" type="button" data-toggle="collapse" data-target=".navbar-collapse"> 
            <span class="sr-only">Toggle navigation</span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
        </button>
    </div>
    <div class="collapse navbar-collapse">
        <div class="container">
            <ul class="nav navbar-nav">
                <li class="dropdown"> <a href="#" tabindex="0" data-toggle="dropdown">Menu<span class="caret"></span></a>

                    <ul class="dropdown-menu" role="menu">
                        <li class="dropdown-submenu"> <a href="#" tabindex="0" data-toggle="dropdown">Sub Menu</a>

                        </li>
                        <li class="dropdown-submenu"> <a href="#" tabindex="0" data-toggle="dropdown">Sub Menu</a>

                        </li>
                    </ul>
                </li>
            </ul>
        </div>
    </div>
</nav>

以下是jsfiddle：https://jsfiddle.net/0jbxzh5w/2/ 全屏预览：https://jsfiddle.net/0jbxzh5w/2/embedded/result/

任何人都能说出我做错了什么？为什么它在firefox中不起作用？

Answer 1

以下是使用css执行此操作的方法：

<强> CSS

@media (min-width: 768px) {
    li.dropdown ul.dropdown-menu {
        display: block;
        opacity: 0;
        left: -100000px;
        -webkit-transform: translate(0, 10px);
        transform: translate(0, 10px);
        -webkit-transition: opacity 250ms, transform 250ms, left 0ms 250ms;
        transition: opacity 250ms, transform 250ms, left 0ms 250ms;
    }

    li.dropdown:hover ul.dropdown-menu {
        opacity: 1;
        left: 0px;
        -webkit-transform: translate(0, 0);
        transform: translate(0, 0);
        -webkit-transition: opacity 250ms, transform 250ms;
        transition: opacity 250ms, transform 250ms;
    }
}

<强> JSFiddle demo

根据我的测试，这适用于Firefox 38

Answer 2

试用此代码

if (matchMedia) {
    var mq = window.matchMedia("(min-width: 768px)");
    mq.addListener(WidthChange);
    WidthChange(mq);
}

function WidthChange(mq) {
    if (mq.matches) {
        $(function () {
            $('li.dropdown').hover(function () {
                $(this).addClass('open');
            }, function () {
                $(this).removeClass('open');
            });
        });
    }
}

@media (min-width: 768px) {
    ul.dropdown-menu {
        opacity: 0;
        transition: all 0.2s linear;
        -webkit-transition: all 0.2s linear;
        -moz-transition: all 0.2s linear;
        transform: translate(0, 10px);
        -webkit-transform: translate(0, 10px);
       -moz-transform: translate(0, 10px);
    }
    li.open > ul.dropdown-menu {
        -webkit-transform: translate(0, 0);
        -moz-transform: translate(0, 0);
        transform: translate(0, 0);
        opacity: 1;
    }
    li.dropdown:hover ul.dropdown-menu {
        display: block !important;
    }
}

<link href="https://jsfiddle.net/0jbxzh5w/1/vsn4ik.github.io/bootstrap-submenu/dist/css/bootstrap-submenu.css" rel="stylesheet"/>
<script src="https://github.com/vsn4ik/bootstrap-submenu/blob/master/js/bootstrap-submenu.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/js/bootstrap.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.4/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<nav class="navbar navbar-default">
    <div class="navbar-header">
        <button class="navbar-toggle" type="button" data-toggle="collapse" data-target=".navbar-collapse"> 
            <span class="sr-only">Toggle navigation</span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
        </button>
    </div>
    <div class="collapse navbar-collapse">
        <div class="container">
            <ul class="nav navbar-nav">
                <li class="dropdown"> <a href="#" tabindex="0" data-toggle="dropdown">Menu<span class="caret"></span></a>

                    <ul class="dropdown-menu" role="menu">
                        <li class="dropdown-submenu"> <a href="#" tabindex="0" data-toggle="dropdown">Sub Menu</a>

                        </li>
                        <li class="dropdown-submenu"> <a href="#" tabindex="0" data-toggle="dropdown">Sub Menu</a>

                        </li>
                    </ul>
                </li>
            </ul>
        </div>
    </div>
</nav>

为什么CSS悬停动画与Firefox的工作方式不同？

2 个答案: