我是css和bootstrap的新手,无法弄清楚如何解决这个问题。欢迎任何帮助。
我的代码有两个问题。
1)当我在小屏幕(移动设备)中单击“欢迎,用户”菜单时,导航栏内的下拉菜单会打开,扭曲栏并更改其高度。我希望它的行为方式与大屏幕(例如桌面)相同。单击时,我希望它在不更改导航栏的情况下打开菜单项,在导航栏前面但不在内部。
2)另一个问题:即使在较大的屏幕上,我也看不到菜单项。项目的某些文本隐藏在屏幕的边缘。我希望菜单完全出现在屏幕上,无论是桌面还是移动。
为了说清楚,我录制了一个非常小的视频来证明这个问题:https://puu.sh/Bq34w/ac56908be0.mp4
完整的代码:https://jsfiddle.net/fredslz/0v7qwjdm/12/
<!doctype html>
<html lang="en">
<body class="text-center">
<nav class="navbar navbar-expand-md navbar-light fixed-top" style="background-color: #FFFFFF;">
<button class="navbar-toggler navbar-nav mr-auto" type="button" data-toggle="collapse" data-target="#navbarCollapse" aria-controls="navbarCollapse" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<a class="navbar-brand mx-auto" href="#">My Brand</a>
<ul class="nav navbar-nav ml-md--auto">
<li class="dropdown">
<a href="#" class="nav-link dropdown-toggle" id="navbarDropdown" data-toggle="dropdown" aria-expanded="false">
Welcome, User <b class="caret"></b>
</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</li>
</ul>
</nav>
</body>
</html>
而CSS:
.navbar {
-webkit-box-shadow: 0 8px 6px -6px #999;
-moz-box-shadow: 0 8px 6px -6px #999;
box-shadow: 0 8px 6px -6px #999;
}
如果您希望菜单项正确对齐,则需要在下拉列表中使用dropdown-menu-right
。
不清楚的是你使用切换器的原因,因为你没有任何可折叠的菜单项(navbar-collapse
)。只需删除切换器并使用navbar-expand
,以便Navbar不会在移动视图中折叠。
<nav class="navbar navbar-expand navbar-light fixed-top" style="background-color: #FFFFFF;">
<a class="navbar-brand mx-auto" href="#">My Brand</a>
<ul class="nav navbar-nav">
<li class="dropdown">
<a href="#" class="nav-link dropdown-toggle" id="navbarDropdown" data-toggle="dropdown" aria-expanded="false">
Welcome, User <b class="caret"></b>
</a>
<div class="dropdown-menu dropdown-menu-right">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</li>
</ul>
</nav>
https://www.codeply.com/go/j1HZLEdyrC
下拉列表将始终在移动折叠的Navbar中打开,这是按设计的。如果您确实希望保留移动切换器,并打算添加可折叠项,则可以在position-absolute
上使用dropdown-menu
来覆盖默认行为。
<nav class="navbar navbar-expand-md navbar-light" style="background-color: #FFFFFF;">
<button class="navbar-toggler navbar-nav mr-auto" type="button" data-toggle="collapse" data-target="#navbarCollapse" aria-controls="navbarCollapse" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<a class="navbar-brand mx-auto" href="#">My Brand</a>
<ul class="nav navbar-nav">
<li class="dropdown">
<a href="#" class="nav-link dropdown-toggle" id="navbarDropdown" data-toggle="dropdown" aria-expanded="false">
Welcome, User <b class="caret"></b>
</a>
<div class="dropdown-menu dropdown-menu-right position-absolute" aria-labelledby="navbarDropdown">
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</li>
</ul>
</nav>
演示两种选择:https://www.codeply.com/go/j1HZLEdyrC
对于移动下拉菜单的问题,您也可以使用它在移动视图中绝对定位:
.navbar-nav .dropdown-menu {
position: absolute;
}
对于下拉列表的对齐,只需将类dropdown-menu-right
添加到dropdown-menu
。
请参阅下面的演示(我已经给了!important
来处理代码段中的级联顺序)和working fiddle here:
.navbar {
-webkit-box-shadow: 0 8px 6px -6px #999;
-moz-box-shadow: 0 8px 6px -6px #999;
box-shadow: 0 8px 6px -6px #999;
/* the rest of your styling */
}
.navbar-nav .dropdown-menu {
position: absolute !important;
}
<script type="text/javascript" src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js"></script>
<link rel="stylesheet" type="text/css" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css">
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js"></script>
<script type="text/javascript" src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"></script>
<nav class="navbar navbar-expand-md navbar-light fixed-top" style="background-color: #FFFFFF;">
<button class="navbar-toggler navbar-nav mr-auto" type="button" data-toggle="collapse" data-target="#navbarCollapse" aria-controls="navbarCollapse" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<a class="navbar-brand mx-auto" href="#">My Brand</a>
<ul class="nav navbar-nav ml-md--auto">
<li class="dropdown">
<a href="#" class="nav-link dropdown-toggle" id="navbarDropdown" data-toggle="dropdown" aria-expanded="false">
Welcome, User <b class="caret"></b>
</a>
<div class="dropdown-menu dropdown-menu-right" aria-labelledby="navbarDropdown">
<!-- ADDED CLASS -->
<a class="dropdown-item" href="#">Action</a>
<a class="dropdown-item" href="#">Another action</a>
<div class="dropdown-divider"></div>
<a class="dropdown-item" href="#">Something else here</a>
</div>
</li>
</ul>
</nav>