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问题:

How to change caret icon on dropdown in bootstrap nav-pills?

I don't know how to use hide.bs.dropdown

<!DOCTYPE html>
<html>
<head>
  <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
  <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" type="text/css">
  <script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
  <style>
     .caret-container {
      float: right;
    }
    .caret.caret-up {
      border-top-width: 0;
      border-bottom: 4px solid;
    }
  </style>
</head>
<body>
  <ul class="nav nav-pills nav-stacked" id="stacked-menu">
    <a href="" class="list-group-item">Quality</a>
    <a href="zertifikate.html" class="list-group-item active">Cert</a>
    <ul class="nav nav-pills nav-stacked collapse in" id="p1">
      <li data-toggle="collapse" data-parent="#p1" href="#pv1">
        <a class="nav-container list-group-item">Leist<div class="caret-container"><span class="caret caret-up"></span></div></a>
      </li>
      <ul class="nav nav-pills nav-stacked collapse out" id="pv1">
        <li><a href="" class="list-group-item">sub1111</a></li>
        <li><a href="" class="list-group-item">sub2222</a></li>
      </ul>
    </ul>
    <a href="" class="list-group-item">Fdsafdsfs</a>
  </ul>
  <script>
    $(document).ready(function(){
      $(".pv1").on("hide.bs.dropdown", function(){
      $(".pv1").html('<span class="caret"></span>');
  });
      $(".collapse").on("show.bs.dropdown", function(){
        $(".btn").html('<span class="caret caret-up"></span>');
      });
    });
  </script>


  
  <script type="text/javascript" src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</body>
</html>

回答1:

Truly saying after Glyphicons and font-awesome published. No one use caret. So are you looking something like this one CaretLiveFiddle .... Or you can try Ghypicons with the nav-pills collapsing GlyphiconsUseForCollapse. If you have any question you can ask me in comment. Thank you.

<!DOCTYPE html>
<html>
<head>
  <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
  <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" type="text/css">
  <script type="text/javascript" src="https://code.jquery.com/jquery-3.1.0.min.js"></script>
 <script type="text/javascript" src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
  <style>
     .caret-container {
      float: right;
    }
   .caret-up{
        border-top-width: 0;
      border-bottom: 4px solid;
   }
  </style>
</head>
<body>
  <ul class="nav nav-pills nav-stacked" id="stacked-menu">
   

 <a href="" class="list-group-item">Quality</a>
    <a href="zertifikate.html" class="list-group-item active">Cert</a>
    <ul class="nav nav-pills nav-stacked collapse in" id="p1">
      <li data-toggle="collapse" data-parent="#p1" href="#pv1">
        <a class="nav-container list-group-item">Leist<div class="caret-container"><span class="caret caret-down"></span></div></a>
      </li>
      <ul class="nav nav-pills nav-stacked collapse out" id="pv1">
        <li><a href="" class="list-group-item">sub1111</a></li>
        <li><a href="" class="list-group-item">sub2222</a></li>
      </ul>
    </ul>
    <a href="" class="list-group-item">Fdsafdsfs</a>
  </ul>
  <script>
  $('.collapse').on('shown.bs.collapse', function() {
  $(this).parent().find(".caret-down").removeClass("caret-down").addClass("caret-up");
}).on('hidden.bs.collapse', function() {
  $(this).parent().find(".caret-up").removeClass("caret-up").addClass("caret-down");
});

  </script>

</body>
</html>

回答2:

$(document).ready(function(){
  $(".pv1").on("hide.bs.dropdown", function(){
  $(".pv1").html('<span class="caret"></span>');
});
  $(".collapse").on("show.bs.dropdown", function(){
    $(".btn").html('<span class="caret caret-up"></span>');
  });
});

Your javascript is referencing pv1 class. You should change it to

$(document).ready(function(){
  $("#pv1").on("hide.bs.dropdown", function(){
  $("#pv1").html('<span class="caret caret-down"></span>');
});
  $(".collapse").on("show.bs.dropdown", function(){
    $(".btn").html('<span class="caret caret-up"></span>');
  });
});

in order to access your element with pv1 id.

Also, as @mhodges points out, add a caret-down to the "hide", so that it changes to down. Otherwise, when it goes back up, it will change to an up caret, and never revert back to down.