Bootstrap4 - 使用剪辑路径属性时，下拉菜单未出现

Question

我使用的剪辑路径属性bootstrap4导航栏。当我用这个，这是对导航栏的下拉菜单无法正常工作。注：请参阅在桌面视图小提琴。

我尝试使用Z-index属性也。但是下拉仍然出现在元素下方。

其实点击它时，下拉应该是在元素上可见。现在看来元素的下方。

.navbar {
  background: #ffcc29;
  padding-bottom: 50px !important;
  -webkit-clip-path: polygon(0 0, 100% 0, 100% 70%, 0% 100%);
  clip-path: polygon(0 0, 100% 0, 100% 70%, 0% 100%);
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>
<nav class="navbar navbar-expand-lg navbar-light">
  <a class="navbar-brand" href="#">Navbar</a> <button aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation" class="navbar-toggler" data-target="#navbarSupportedContent" data-toggle="collapse" type="button"><span class="navbar-toggler-icon"></span></button>
  <div class="collapse navbar-collapse" id="navbarSupportedContent">
    <form class="form-inline my-2 my-lg-0">
      <input aria-label="Search" class="form-control mr-sm-2" placeholder="Search" type="search"> <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
    </form>
    <ul class="navbar-nav ml-auto">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item dropdown">
        <a aria-expanded="false" aria-haspopup="true" class="nav-link dropdown-toggle" data-toggle="dropdown" href="#" id="navbarDropdown" role="button">Dropdown</a>
        <div aria-labelledby="navbarDropdown" class="dropdown-menu">
          <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> <a class="dropdown-item" href="#">Something else here</a> <a class="dropdown-item" href="#">Something else here</a> <a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item"
            href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a>
          <a
            class="dropdown-item" href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a>
        </div>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Link</a>
      </li>
      <li class="nav-item">
        <a class="nav-link disabled" href="#">Disabled</a>
      </li>
    </ul>
  </div>
</nav>

Answer 1

嗯，这是怎么夹路径工作。

CSS中的clip-path属性允许您指定一个元素的特定区域进行显示，而不是显示完整的区域。

因此，它隐藏元素的其余部分。

你可以实现你使用伪元素，在下面的示例中呈三角形，像要在其他方面的东西，例如。或jsFIddle

.navbar {
  background: #ffcc29;
  padding-bottom: 50px !important;
}

.navbar:after {
  content: "";
  position: absolute;
  bottom: 0;
  right: 0;
  width: 0;
  height: 0;
  border-width: 30px 100vw 0px 0;
  border-color: transparent white transparent transparent;
  border-style: solid;
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>
<nav class="navbar navbar-expand-lg navbar-light">
  <a class="navbar-brand" href="#">Navbar</a> <button aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation" class="navbar-toggler" data-target="#navbarSupportedContent" data-toggle="collapse" type="button"><span class="navbar-toggler-icon"></span></button>
  <div class="collapse navbar-collapse" id="navbarSupportedContent">
    <form class="form-inline my-2 my-lg-0">
      <input aria-label="Search" class="form-control mr-sm-2" placeholder="Search" type="search"> <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
    </form>
    <ul class="navbar-nav ml-auto">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item dropdown">
        <a aria-expanded="false" aria-haspopup="true" class="nav-link dropdown-toggle" data-toggle="dropdown" href="#" id="navbarDropdown" role="button">Dropdown</a>
        <div aria-labelledby="navbarDropdown" class="dropdown-menu">
          <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> <a class="dropdown-item" href="#">Something else here</a> <a class="dropdown-item" href="#">Something else here</a> <a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item"
            href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a>
          <a class="dropdown-item" href="#">Something else here</a><a class="dropdown-item" href="#">Something else here</a>
        </div>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Link</a>
      </li>
      <li class="nav-item">
        <a class="nav-link disabled" href="#">Disabled</a>
      </li>
    </ul>
  </div>
</nav>