时间戳

首页 > 解决方案 > 捕捉 .bs.dropdown 事件

javascript - 捕捉 .bs.dropdown 事件

问题描述

我正在尝试从引导下拉列表中捕获事件。似乎没有任何效果，尽管很明显我做错了什么。

代码，简化为问题......

<!DOCTYPE html>

<html>
    <head>
        <meta charset="UTF-8">
        <meta http-equiv="X-UA-Compatible" content="IE=edge">
        <meta name="viewport" content="width=device-width, initial-scale=1, minimum-scale=1">
        <title>Demo</title>
        <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
        <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.0/jquery.js" integrity="sha256-DYZMCC8HTC+QDr5QNaIcfR7VSPtcISykd+6eSmBW5qo=" crossorigin="anonymous"></script>
    </head>

    <body>
        <div class="navbar">
            <a class="nav-link dropdown-toggle" href="#" id="search_drop" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              Search
            </a>

            <div class="dropdown-menu" aria-labelledby="search_drop">
                <h2 class="text-primary">Search</h2>
                <form class="navbar-form navbar-right navbar-expand-xl" id="header-searchForm">
                    <input type="text" class="form-control" placeholder="enter terms" name="Search" aria aria-selected="true" id="search_str" required="true">
                    <button type="submit" class="btn btn-sm btn-primary">
                        Search
                    </button>
                </form>
            </div>      
        </div>

        <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.bundle.min.js" integrity="sha384-xrRywqdh3PHs8keKZN+8zzc5TX0GRTLCcmivcbNJWm2rs5C8PRhcEn3czEjhAO9o" crossorigin="anonymous"></script>
        <script type="text/javascript">
            $('#search_drop').on('show.bs.dropdown', function() {
                console.log("show");
            }).on('shown.bs.dropdown', function() {
                console.log("shown");
            }).on('hide.bs.dropdown', function() {
                console.log("hide");
            }).on('hidden.bs.dropdown', function() {
                console.log("hidden");
            });
        </script>

    </body>
</html>

没有一个console.log声明受到打击。

标签： javascriptjqueryhtmlbootstrap-4

解决方案

您需要将触发按钮包装在具有下拉类的元素中，并定位到：

所有下拉事件都在 .dropdown-menu 的父元素上触发，并具有一个 relatedTarget 属性，其值是切换锚元素。

和...

将下拉菜单的切换（您的按钮或链接）和下拉菜单包装在 .dropdown 或另一个声明位置的元素中：relative;。

$('.dropdown').on('show.bs.dropdown', function() {
  console.log("show");
}).on('shown.bs.dropdown', function() {
  console.log("shown");
}).on('hide.bs.dropdown', function() {
  console.log("hide");
}).on('hidden.bs.dropdown', function() {
  console.log("hidden");
});
<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>

<div class="navbar">
  <div class="dropdown">
    <a class="nav-link dropdown-toggle" href="#" id="search_drop" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              Search
            </a>

    <div class="dropdown-menu" aria-labelledby="search_drop">
      <h2 class="text-primary">Search</h2>
      <form class="navbar-form navbar-right navbar-expand-xl" id="header-searchForm">
        <input type="text" class="form-control" placeholder="enter terms" name="Search" aria aria-selected="true" id="search_str" required="true">
        <button type="submit" class="btn btn-sm btn-primary">
                        Search
                    </button>
      </form>
    </div>
  </div>
</div>

推荐阅读