我正在制作导航标签,需要有一个元素只显示在活动的一个。在我的例子中,是指向内容的白色箭头。当你点击另一个标签时,我怎么能让它消失呢?或者,我怎样才能把它移到那个标签上,让它指向它的内容呢?
以下是我的代码大纲:
.arrow-down {
position: absolute;
width: 0;
height: 0;
border-left: 15px solid transparent;
border-right: 15px solid transparent;
border-top: 15px solid white;
margin-left: 20px;
}
.nav-tabs {
background-color: black;
}
.tab-content {
background-color: #ccc
}
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css" integrity="sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.1.1.slim.min.js" integrity="sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/tether/1.4.0/js/tether.min.js" integrity="sha384-DztdAPBWPRXSA/3eYEEUWrWCy7G5KFbe8fFjk5JAIxUYHKkDx6Qin1DkWx51bBrb" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/js/bootstrap.min.js" integrity="sha384-vBWWzlZJ8ea9aCX4pEW3rVHjgjt7zpkNpZk+02D9phzyeVkE+jo0ieGizqPLForn" crossorigin="anonymous"></script>
<ul class="nav nav-tabs" role="tablist">
<li class="nav-item">
<a class="nav-link active" data-toggle="tab" href="#home" role="tab">Home</a>
<div class="arrow-down"></div>
</li>
<li class="nav-item">
<a class="nav-link" data-toggle="tab" href="#profile" role="tab">Profile</a>
</li>
<li class="nav-item">
<a class="nav-link" data-toggle="tab" href="#messages" role="tab">Messages</a>
</li>
<li class="nav-item">
<a class="nav-link" data-toggle="tab" href="#settings" role="tab">Settings</a>
</li>
</ul>
<div class="tab-content">
<div class="tab-pane active" id="home" role="tabpanel">...</div>
<div class="tab-pane" id="profile" role="tabpanel">...</div>
<div class="tab-pane" id="messages" role="tabpanel">...</div>
<div class="tab-pane" id="settings" role="tabpanel">...</div>
</div>
最佳答案
添加一个类以显示箭头,然后将单击事件添加到所有菜单,删除上一个箭头并添加到当前选项卡。
.active-arrow {
display: block;
}
要使箭头居中,可以使用flexbox,并将
margin-top
添加到每个箭头以将其向右定位。.nav-item {
display: flex;
align-items: center;
justify-content: center;
}
$('ul a.nav-link').on('click', function(e) {
$('.arrow-down').removeClass('active-arrow');
$(this).next('.arrow-down').addClass('active-arrow');
})
.arrow-down {
position: absolute;
width: 0;
height: 0;
border-left: 15px solid transparent;
border-right: 15px solid transparent;
border-top: 15px solid white;
display: none;
margin-top: 28px;
}
.nav-item {
display: flex;
align-items: center;
justify-content: center;
}
.active-arrow {
display: block;
}
.nav-tabs {
background-color: black;
}
.tab-content {
background-color: #ccc
}
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css" integrity="sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.1.1.slim.min.js" integrity="sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/tether/1.4.0/js/tether.min.js" integrity="sha384-DztdAPBWPRXSA/3eYEEUWrWCy7G5KFbe8fFjk5JAIxUYHKkDx6Qin1DkWx51bBrb" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/js/bootstrap.min.js" integrity="sha384-vBWWzlZJ8ea9aCX4pEW3rVHjgjt7zpkNpZk+02D9phzyeVkE+jo0ieGizqPLForn" crossorigin="anonymous"></script>
<ul class="nav nav-tabs" role="tablist">
<li class="nav-item">
<a class="nav-link active" data-toggle="tab" href="#home" role="tab">Home</a>
<div class="arrow-down active-arrow"></div>
</li>
<li class="nav-item">
<a class="nav-link" data-toggle="tab" href="#profile" role="tab">Profile</a>
<div class="arrow-down"></div>
</li>
<li class="nav-item">
<a class="nav-link" data-toggle="tab" href="#messages" role="tab">Messages</a>
<div class="arrow-down"></div>
</li>
<li class="nav-item">
<a class="nav-link" data-toggle="tab" href="#settings" role="tab">Settings</a>
<div class="arrow-down"></div>
</li>
</ul>
<div class="tab-content">
<div class="tab-pane active" id="home" role="tabpanel">1</div>
<div class="tab-pane" id="profile" role="tabpanel">2</div>
<div class="tab-pane" id="messages" role="tabpanel">3</div>
<div class="tab-pane" id="settings" role="tabpanel">4</div>
</div>