我只是切换到bootstrap 4和重做我所有的html和scss与它一起工作,我似乎不知道如何把一组导航项在导航栏的右侧。这是我的导航条码:

<nav class="navbar navbar-full navbar-dark bg-primary">
        <button class="navbar-toggler hidden-md-up" type="button" data-toggle="collapse" data-target="#navbarResponsive" aria-controls="navbarResponsive" aria-expanded="false" aria-label="Toggle navigation"></button>
        <%= link_to "Living Recipe", recipes_path(sort_attribut: "popularity", sort_order: :desc), class: "navbar-brand" %>
        <div class="collapse navbar-toggleable-sm" id="navbarResponsive">   
            <ul class="nav navbar-nav float-md-left">
                <li class="nav-item">
                    <%= form_tag(recipes_path, :method => "get", id: "search-form", class: "form-inline") do %>
                            <%= text_field_tag :search, params[:search], placeholder: "Search Recipes", class: "form-control col-md-8" %>
                    <% end %>
                </li>
                <li class="nav-item dropdown">
                    <a class="nav-link dropdown-toggle" href="http://example.com" id="responsiveNavbarDropdown" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Browse</a>
                    <div class="dropdown-menu" aria-labelledby="responsiveNavbarDropdown">
                        <%= link_to "Popular", recipes_path(sort_attribute: "popularity", sort_order: :desc), class: "dropdown-item" %>
                        <%= link_to "Newest", recipes_path(sort_attribute: "created_at", sort_order: :desc), class: "dropdown-item" %>
                        <%= link_to "Most Updated", recipes_path(sort_attribute: "most_active", sort_order: :desc), class: "dropdown-item" %>
                        <%= link_to "Most Saved", recipes_path(sort_attribute: "save_count", sort_order: :desc), class: "dropdown-item" %>
                    </div>
                </li>
            </ul>
            <ul class="nav navbar-nav float-md-right">
                <% if user_signed_in? %>
                    <li class="dropdown">
                        <a class="nav-link dropdown-toggle" href="http://example.com" id="navbarDropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
                            <%= current_user.displayname.present? ? "D-ring" : current_user.firstname %>
                        </a>
                        <div class="dropdown-menu" aria-labelledby="responsiveNavbarDropdown">
                            <%= link_to "Profile", user_path(current_user.id), class: "dropdown-item" %>
                            <%= link_to "Recipe Box", user_saved_recipes_path(current_user.id), class: "dropdown-item" %>
                            <%= link_to "Add Recipe", new_recipe_path, class: "dropdown-item" %>
                            <%= link_to "Submitted Recipes", user_path(current_user.id), class: "dropdown-item" %>
                            <%= link_to "Sign Out", destroy_user_session_path, :method => :delete, class: "dropdown-item" %>
                        </div>
                    </li>
                <% else %>
                    <li class="nav-item">
                        <%= link_to "Create Account", '', data: {:'toggle' => 'modal', :'target' => '#signupModal'}, class: "nav-link" %>
                    </li>
                    <li class="nav-item">
                        <%= link_to "Login", '', data: {:'toggle' => 'modal', :'target' => '#loginModal'}, class: "nav-link" %>
                    </li>           
                <% end %>
            </ul>
        </div>
    </nav>

这是它的截图


当前回答

在上一个版本中,它更简单。只需要在ul中放入一个ml-auto类,如下所示:

<ul class="nav navbar-nav ml-auto">

其他回答

在上一个版本中,它更简单。只需要在ul中放入一个ml-auto类,如下所示:

<ul class="nav navbar-nav ml-auto">

使用Bootstrap v4.0.0-alpha。6:两个<ul>s (.navbar-na),一个带有。mr-auto,一个带有。ml-auto:

<nav ...> 
  ...     
  <div class="collapse navbar-collapse">
    <ul class="navbar-nav mr-auto">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Left Link </a>
      </li>
    </ul>
    <ul class="navbar-nav ml-auto">
      <li class="nav-item">
        <a class="nav-link" href="#">Right Link </a>
      </li>
    </ul>
  </div>
</nav>

TL; diana:

为右侧的导航栏项创建另一个<ul class="navbar-nav ml-auto">。 Ml-auto会把你的导航条拉到右边,而mr-auto会把它拉到左边。

根据引导程序v4.5.2进行测试

<!DOCTYPE html> <html lang="en"> <head> <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css"/> <style> /* Stackoverflow preview fix, please ignore */ .navbar-nav { flex-direction: row; } .nav-link { padding-right: .5rem !important; padding-left: .5rem !important; } /* Fixes dropdown menus placed on the right side */ .ml-auto .dropdown-menu { left: auto !important; right: 0px; } </style> </head> <body> <nav class="navbar navbar-expand-lg navbar-dark bg-primary rounded"> <a class="navbar-brand" href="#">Navbar</a> <ul class="navbar-nav mr-auto"> <li class="nav-item active"> <a class="nav-link">Left Link 1</a> </li> <li class="nav-item"> <a class="nav-link">Left Link 2</a> </li> </ul> <ul class="navbar-nav ml-auto"> <li class="nav-item"> <a class="nav-link">Right Link 1</a> </li> <li class="nav-item dropdown"> <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false"> Dropdown on Right</a> <div class="dropdown-menu" aria-labelledby="navbarDropdown"> <a class="dropdown-item" href="#">Action</a> <a class="dropdown-item" href="#">Another action with a lot of text inside of an item</a> </div> </li> </ul> </nav> <script src="https://code.jquery.com/jquery-3.2.1.slim.min.js"></script> <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"></script> </body> </html>

正如你所看到的,在Stackoverflows预览框中添加了一些奇怪的样式规则。 您应该能够在项目中安全地忽略这些规则。

从v4.0.0开始,这似乎是官方的方式。

编辑:根据@Bruno的建议,我修改了帖子,在导航栏右侧添加了一个下拉菜单。它需要它的左属性和右属性颠倒。我在示例代码的开头添加了一个额外的css代码片段。 请注意,当单击Run代码片段按钮时,示例将显示移动版本。要查看桌面版本,必须单击“展开代码片段”按钮。

.ml-auto .dropdown-menu {
    left: auto !important;
    right: 0px;
}

在样式表中包含这一点就可以了。

在Bootstrap 4 alpha-6版本中,由于导航栏使用flex模型,您可以在父div中使用justify-content-end并删除mr-auto。

<div class="collapse navbar-collapse justify-content-end" id="navbarText">
  <ul class="navbar-nav">
    <li class="nav-item active">
      <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
    </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>

这就像一个咒语一样:)

在我的情况下,我正在寻找一个解决方案,允许一个导航栏项目是右对齐。为了做到这一点,你必须添加style="width:100%;"到<ul class="navbar-nav">,然后添加ml-auto类到你的导航栏项目。