过滤搜索中的ajax调用无效

Question

我有引导标签和过滤器。当用户选择过滤器并提交时，将生成ajax调用，并且选项卡应显示内容。

<ul class="nav nav-tabs " role="tablist">
<li class="active col-md-3"><a data-toggle="tab" href="#home">Notes</a></li>
<li class="col-md-3"><a data-toggle="tab"  href="#menu1">Question Bank</a></li>
<li class="col-md-3"><a data-toggle="tab" href="#menu2">Summary</a></li>
<li class="col-md-3"><a data-toggle="tab"  href="#menu3">Videos</a></li>
 </ul>
 <hr>
<div class="tab-content">
<div id="home" class="tab-pane fade in active">
 <?php 
include "notes.php"
?>
<br><br><hr>
<div class="col-md-12"> 
</div>
</div>

Notes.php包含过滤器的代码，其形式为

 <script type="text/javascript">
 $(function(){
 $('input[type=submit]').click(function(){
    $.ajax({
        type: "GET",
        url: "filter_form.php",
        data: $("#filter_search").serialize(),
        beforeSend: function(){
            $('#home').html('<img src="/img/loading.gif" />');
        },
        success: function(data){
            $('#home').html(data);
        }
    });
});
});
</script>  

form action="" method="GET" id="filter_search">
<ul class="nav navbar-nav container-fluid col-md-12">

      <li class="col-md-3">
      <select class="form-control dropdown-toggle" data-toggle="dropdown" name="select_category">

       <option value="category">Select Category</option>

                    <?php
                        $sql1 = mysqli_query($conn,"call category_dropdown()");
                        while($row = mysqli_fetch_array($sql1))
                        {   

                            echo "<option value='" . $row['category'] ."'>" . $row['category'] . "</option>";
                        }
                        mysqli_free_result($sql1);
                        mysqli_next_result($conn);
                    ?> 
                </select>



    </li>
   <li class="col-md-3">
      <select class="form-control dropdown-toggle" data-toggle="dropdown"     name="select_course"></a>

          <option value="course">Select Course</option>

                    <?php
                        $sql2 = mysqli_query($conn,"call courses_dropdown()");
                        while($row = mysqli_fetch_array($sql2))
                        {   

                            echo "<option value='" . $row['courses'] ."'>" . $row['courses'] . "</option>";
                        }
                        mysqli_free_result($sql2);
                        mysqli_next_result($conn);
                    ?> 
                </select>


    </li>

        <li class="col-sm-3">
        <select class="form-control dropdown-toggle"  name="select_subject">
        <option value="subjects">Select Subjects</option> 
        <?php
         $sql3 = mysqli_query($conn,"call subject_dropdown()");
         while($row = mysqli_fetch_array($sql3))
         {   
             echo "<option value='" . $row['subjects'] ."'>" . $row['subjects'] . "</option>";
          }
          mysqli_free_result($sql3);
                        mysqli_next_result($conn);
        ?>
        </select> 

    </li>

    <li class="col-md-3">
        <input type="submit"  name="filter" class="btn form-control btn-warning" value="Filter Results">
    </li>   
</ul>
</form>  

filter_search.php

     <?php
  include 'includes/dbconfig.php';
  if(isset($_GET['id']))
                        {
                            $id=$_GET['id'];
                            $start=($id-1)*$limit;
                        }
                        else{
                            $id=1;
                        }
     if(isset($_GET['filter']))
                  {
                    $start = 0;
                    $limit = 16;
                    $category = $_GET['select_category'];
                    $course = $_GET['select_course'];
                    $subject = $_GET['select_subject'];
                          $sql = mysqli_query($conn,"call   filter('category','course','subject')") or die('Query failed: '. mysqli_error($conn));

                          while($row = mysqli_fetch_array($sql))
                          {   
                            $title = $row['title'];
                            $description = $row['description'];
                            $url = $row['content_url'];
                            $icon = $row['thumb_icon'];

                          ?>

                        <div class="col-md-3">
                                 <a href="<?php echo $url ;?>">
                              <div class="well well-sm">
                              <img class="img" alt="PDF" src="<?php echo $icon ;?>" >

                              <h4><small><?php echo $title ; ?></small></h4>

                              <p> <a data-toggle="modal" data-target="#myModal">Preview</a></p>
                              </div>

                          </a>

                      </div>

        <?php
     }
        }
       ?>