如何使Bootstrap下拉列表符合移动设备上的水平视口限制? [英] How to make Bootstrap dropdown respect horizontal viewport limits on mobile?

问题描述

Bootstrap类 dropdown-menu 可以自动检测屏幕的视口并进行相应调整

Bootstrap class dropdown-menu can autodetect the viewport of the screen and adapt accordingly

因此，如果没有足够的空间可以打开下拉菜单的底部，如下面的示例所示，则打开

So if there is no room for the dropdown to open to the bottom it opens up, as shown by the example bellow

但是对于视口的水平限制并没有发生这种情况，我最终得到了这种水平滚动，这是发生这种情况的一个示例:

However it doesn't happen for the horizontal limits of the viewport, and I end up getting this horizontal scroll, here's an example of this happening:

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"></script>
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" rel="stylesheet"/>

<div class="bd-example">
  <div class="btn-group">
    <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Primary</button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Secondary</button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-success dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Success</button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-info dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Info</button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-warning dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Warning</button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-danger dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Danger</button>
    <div class="dropdown-menu">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
</div>

我还创建了一个gif演示了我的意思:

I also created a gif demonstrating exacly what I mean:

如何重现与垂直视口检测相同的行为以重新定位元素?理想情况下，它应该看起来像这样，使其与按钮的另一端对齐.

How can I reproduce the same behavior as vertical viewport detection to reposition the element? Ideally it should look like this, aligning itself with the other end of the button.

推荐答案

在所有具有类 dropdown-menu 的地方添加 dropdown-menu-right 类，并且 dropdown-menu-right 应该是第二位.即 class ="dropwdown-menu dropdown-menu-right"

Everywhere you have the class dropdown-menu add dropdown-menu-right Note that you need both classes, and dropdown-menu-right should be second. i.e. class="dropwdown-menu dropdown-menu-right"

这应该让您拥有这个:

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"></script>
<link href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" rel="stylesheet"/>

<div class="bd-example">
  <div class="btn-group">
    <button type="button" class="btn btn-primary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Primary</button>
    <div class="dropdown-menu dropdown-menu-right">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Secondary</button>
    <div class="dropdown-menu dropdown-menu-right">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-success dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Success</button>
    <div class="dropdown-menu dropdown-menu-right">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-info dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Info</button>
    <div class="dropdown-menu dropdown-menu-right">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-warning dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Warning</button>
    <div class="dropdown-menu dropdown-menu-right">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
  <div class="btn-group">
    <button type="button" class="btn btn-danger dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">Danger</button>
    <div class="dropdown-menu dropdown-menu-right">
      <a class="dropdown-item" href="#">Action</a>
      <a class="dropdown-item" href="#">Another action</a>
      <a class="dropdown-item" href="#">Something else here</a>
      <div class="dropdown-divider"></div>
      <a class="dropdown-item" href="#">Separated link</a>
    </div>
  </div><!-- /btn-group -->
</div>

这篇关于如何使Bootstrap下拉列表符合移动设备上的水平视口限制?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！