Question

我有一个导航栏，其中有li项居中。将其中两个li悬停在它们上面时，应该有一个下拉菜单。我尝试了此操作，但dropdown-content出现在导航栏容器中。我使用.dropdown进行了尝试，将鼠标悬停在它上面时，在导航栏的红色边框下应该可以看到.dropdwon-content。

我的代码：

function resNavBar() {
  var x = document.getElementById("idTopNav");
  var y = document.getElementById("idHomeBtn");
  var z = document.getElementById("idIconClose");
  var zz = document.getElementById("idIconMenu");
  if (x.className === "topnav" & y.className === "homebtn") {
    x.className += " responsive";
    y.className += " responsive";
    z.className = "icon-close";
    zz.className += " invisible";
  } else {
    x.className = "topnav";
    y.className = "homebtn";
    z.className += " invisible";
    zz.className = "icon-menu";
  }
}

* {
  padding: 0;
  margin: 0;
  font-family: 'Roboto', sans-serif;
}

body {
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
  padding: 0;
  margin: 0;
  height: 100%;
}

html {
  height: 100%;
}

body * {
  -webkit-box-sizing: border-box;
  box-sizing: border-box;
}

header .topnav {
  background-color: #201D1D;
  overflow: hidden;
  border-bottom: 4px solid #A90101;
}

header .topnav li {
  list-style: none;
  list-style-type: none;
}

header .topnav li a {
  color: #fff;
  display: block;
  text-align: center;
  float: left;
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 25px;
  text-decoration: none;
  padding: 0.5em 1.2em;
}

header .topnav li a:hover {
  background-color: #A90101;
  color: #201D1D;
}

header .topnav .icon-home {
  display: none;
  font-size: 1.5rem;
  padding: 0.5em 1em;
  color: #fff;
}

header .topnav .topnav a.icon-menu,
header .topnav .topnav a.icon-close {
  display: none;
}

header .topnav .dropdown {
  position: relative;
  display: inline-block;
}

header .topnav .dropdown .dropdown-content {
  display: none;
  position: absolute;
  background-color: #f8f9fa;
  min-width: 10vw;
  z-index: 1;
  padding: 12px 16px;
}

header .topnav .dropdown:hover .dropdown-content {
  display: block;
}

// Responsive: 
@media screen and (max-width: 1000px) {
  .topnav ul li a {
    display: none;
  }
  .topnav a.icon-home {
    float: left;
    display: block;
  }
  .topnav a.icon-menu {
    float: right;
    display: block;
    font-size: 1.5rem;
    padding: 0.5em 1em;
    color: #fff;
  }
  .topnav a.icon-close {
    float: right;
    display: block;
    font-size: 1.6rem;
    padding: 0.5em 1em;
    color: #fff;
  }
}

@media screen and (max-width: 1000px) {
  .topnav.responsive {
    position: relative;
  }
  .topnav.responsive a.icon-home {
    position: absolute;
    right: 0;
    top: 0;
  }
  .topnav.responsive a.icon-menu {
    position: absolute;
    right: 0;
    top: 0;
  }
  .topnav.responsive a.icon-close {
    position: absolute;
    right: 0;
    top: 0;
  }
  .topnav.responsive a {
    float: none;
    display: block;
    text-align: left;
  }
  .homebtn.responsive {
    display: none;
  }
  .topnav a.icon-close.invisible {
    display: none;
  }
  .topnav a.icon-menu.invisible {
    display: none;
  }
}

@media screen and (min-width: 1000px) {
  .topnav-mid {
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    text-align: center;
    -webkit-box-align: center;
    -ms-flex-align: center;
    align-items: center;
    -webkit-box-pack: center;
    -ms-flex-pack: center;
    justify-content: center;
  }
  .topnav a.icon-close {
    display: none;
  }
  .topnav a.icon-menu {
    display: none;
  }
}

<!---HTML:--->

<header>
  <nav class="topnav">
    <div class="homebtn" id="idHomeBtn">
      <a href="index.html" class="icon-home" onclick="none">
        <i class="fas fa-home"></i>
      </a>
    </div>

    <ul class="topnav-mid">
      <li><a href="#">link</a></li>
      <li><a href="#">link</a></li>
      <li><a href="#">link</a></li>

      <li class="dropdown"><a href="#">link</a>
        <!--! DROPDOWN -->
        <div class="dropdown-content dropdown-content-about">
          <a href="#">link</a>

          <li><a href="#">link</a></li>
    </ul>

    <a href="javascript:void(0);" class="icon-close invisible" id="idIconClose" onclick="resNavBar()">
      <i class="fas fa-times"></i>
    </a>

    <a href="javascript:void(0);" class="icon-menu" id="idIconMenu" onclick="resNavBar()">
      <i class="fas fa-bars"></i>
    </a>
  </nav>
</header>


<script src="js/responsive.js"></script>

有人知道为什么下拉列表在导航栏中吗？

Answer 1

该下拉菜单位于导航栏中，因为您没有为其指定位置。只需将top属性添加到.dropdown-content。

header .topnav .dropdown .dropdown-content {
  display: none;
  position: absolute;
  background-color: #f8f9fa;
  min-width: 10vw;
  z-index: 1;
  padding: 12px 16px;
  top: 100%;
}

您需要摆脱.topnav元素上的溢出。

导航栏中的CSS下拉菜单不起作用-下拉菜单显示在导航栏中

1 个答案: