i have problem when adding a subject it got two subject that need to be selected by teacher , management sub and DBMS sub.. said Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\PhpProject3\navhead_user.php:57) in C:\xampp\htdocs\PhpProject3\teacher_add_subject.php on line 104.. when i select one of them it appear that error.. but when i select DBMS it inserted the subject but with error.. let say 1st i selecting management as the subject, it occur error but after refresh the page it appear in the list of the teacher subject then i add another subject DBMS subject and it occur error but the management subject is dissappear from the teach subject list.. but i try to add the management subject again it said it existed but not listed.. but in my database it inside there already only the data not appear..
teacher_add_subject.php
<?php include ('session.php'); ?>
<?php
include('header.php');
$user_query = mysql_query("select * from teacher where teacher_id='$session_id'") or die(mysql_error());
$user_row = mysql_fetch_array($user_query);
?>
<body>
<?php include('navhead_user.php'); ?>
<div class="container">
<div class="row-fluid">
<div class="span3">
<div class="hero-unit-3">
<div class="alert-index alert-success">
<i class="icon-calendar icon-large"></i>
<?php
$Today = date('y:m:d');
$new = date('l, F d, Y', strtotime($Today));
echo $new;
?>
</div>
</div>
<div class="hero-unit-1">
<ul class="nav nav-pills nav-stacked">
<li class="nav-header">Links</li>
<li>
<a href="teacher_home.php"><i class="icon-home icon-large"></i> Home
<div class="pull-right">
<i class="icon-double-angle-right icon-large"></i>
</div>
</a>
</li>
<li>
<a href="teacher_class.php"><i class="icon-group icon-large"></i> Class
<div class="pull-right">
<i class="icon-double-angle-right icon-large"></i>
</div>
</a></li>
<li class="active"><a href="teacher_subject.php"><i class="icon-file-alt icon-large"></i> Subjects
<div class="pull-right">
<i class="icon-double-angle-right icon-large"></i>
</div>
</a></li>
<li><a href="students.php"><i class="icon-group icon-large"></i> Students
<div class="pull-right">
<i class="icon-double-angle-right icon-large"></i>
</div>
</a></li>
</ul>
</div>
</div>
<div class="span9">
<a href="teacher_subject.php" class="btn btn-success"><i class="icon-arrow-left icon-large"></i> Back</a>
<br>
<br>
<div class="alert alert-info">
<button type="button" class="close" data-dismiss="alert">×</button>
<strong><i class="icon-user icon-large"></i> Add Subject</strong>
</div>
<div class="hero-unit-2">
<form class="form-horizontal" method="POST">
<div class="control-group">
<label class="control-label" for="inputEmail">Subject</label>
<div class="controls">
<select name="subject" class="span6">
<option></option>
<?php
$query = mysql_query("select * from subject") or die(mysql_error());
while ($row = mysql_fetch_array($query)) {
?>
<option value="<?php echo $row['subject_id']; ?>"><?php echo $row['subject_title']; ?></option>
<?php } ?>
</select>
</div>
</div>
<div class="control-group">
<div class="controls">
<button type="submit" name="save_subject" class="btn btn-success"><i class="icon-plus-sign icon-large"></i> Add Subject</button>
</div>
<br>
<?php
if (isset($_POST['save_subject'])) {
$subject = $_POST['subject'];
$result = mysql_query("select * from teacher_suject where teacher_id='$session_id' and subject_id='$subject'") or die(mysql_error());
$count = mysql_num_rows($result);
if ($count > 0) {
?>
<div class="alert alert-danger">Subject <strong>Already Exist</strong></div>
<?php
} else {
mysql_query("insert into teacher_suject (subject_id,teacher_id) values('$subject','$session_id')") or die(mysql_error());
header('location:teacher_subject.php');
}
}
?>
</div>
</form>
<!-- end slider -->
</div>
</div>
</div>
<?php include('footer.php'); ?>
</div>
</div>
</div>
</body>
</html>
teacher_subject.php
<?php include ('session.php'); ?>
<?php
include('header.php');
$user_query = mysql_query("select * from teacher where teacher_id='$session_id'") or die(mysql_error());
$user_row = mysql_fetch_array($user_query);
?>
<body>
<?php include('navhead_user.php'); ?>
<div class="container">
<div class="row-fluid">
<div class="span3">
<div class="hero-unit-3">
<div class="alert-index alert-success">
<i class="icon-calendar icon-large"></i>
<?php
$Today = date('y:m:d');
$new = date('l, F d, Y', strtotime($Today));
echo $new;
?>
</div>
</div>
<div class="hero-unit-1">
<ul class="nav nav-pills nav-stacked">
<li class="nav-header">Links</li>
<li>
<a href="teacher_home.php"><i class="icon-home icon-large"></i> Home
<div class="pull-right">
<i class="icon-double-angle-right icon-large"></i>
</div>
</a>
</li>
<li>
<a href="teacher_class.php"><i class="icon-group icon-large"></i> Class
<div class="pull-right">
<i class="icon-double-angle-right icon-large"></i>
</div>
</a></li>
<li class="active"><a href="teacher_subject.php"><i class="icon-file-alt icon-large"></i> Subjects
<div class="pull-right">
<i class="icon-double-angle-right icon-large"></i>
</div>
</a></li>
<li><a href="students.php"><i class="icon-group icon-large"></i> Students
<div class="pull-right">
<i class="icon-double-angle-right icon-large"></i>
</div>
</a></li>
</ul>
</div>
</div>
<div class="span9">
<a href="teacher_add_subject.php" class="btn btn-success"><i class="icon-plus-sign icon-large"></i> Add Subject</a>
<br>
<br>
<div class="hero-unit-3">
<table cellpadding="0" cellspacing="0" border="0" class="table table-striped table-bordered" id="example">
<div class="alert alert-info">
<button type="button" class="close" data-dismiss="alert">×</button>
<strong><i class="icon-user icon-large"></i> Subject Table</strong>
</div>
<thead>
<tr>
<th>Course Code</th>
<th>Course Description</th>
<th>Action</th>
</tr>
</thead>
<tbody>
<?php
$teacher_subject_query = mysql_query("select * from teacher_suject where teacher_id='$session_id'") or die(mysql_error());
$teacher_row = mysql_fetch_array($teacher_subject_query);
$subject_id = $teacher_row['subject_id'];
$query = mysql_query("select * from subject where subject_id = '$subject_id'") or die(mysql_error());
while ($row = mysql_fetch_array($query)) {
$id = $row['subject_id'];
?>
<!-- script -->
<script type="text/javascript">
$(document).ready(function(){
$('#d<?php echo $subject_id; ?>').tooltip('show')
$('#d<?php echo $subject_id; ?>').tooltip('hide')
});
</script>
<!-- end script -->
<!-- script -->
<script type="text/javascript">
$(document).ready(function(){
$('#e<?php echo $subject_id; ?>').tooltip('show')
$('#e<?php echo $subject_id; ?>').tooltip('hide')
});
</script>
<!-- end script -->
<tr class="odd gradeX">
<td><?php echo $row['subject_code']; ?></td>
<td><?php echo $row['subject_title']; ?></td>
<td width="50">
<a rel="tooltip" title="Delete Subject" id="d<?php echo $subject_id; ?>" href="#id<?php echo $id; ?>" role="button" data-toggle="modal" class="btn btn-danger"><i class="icon-trash icon-large"></i> </a>
</td>
<!-- user delete modal -->
<div id="id<?php echo $id; ?>" class="modal hide fade" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
<div class="modal-header">
</div>
<div class="modal-body">
<div class="alert alert-danger">Are you Sure you Want to <strong>Delete</strong> this Subject?</div>
</div>
<div class="modal-footer">
<button class="btn" data-dismiss="modal" aria-hidden="true"><i class="icon-remove icon-large"></i> Close</button>
<a href="delete_teacher_course.php<?php echo '?id=' . $course_id; ?>" class="btn btn-danger"><i class="icon-trash icon-large"></i> Delete</a>
</div>
</div>
<!-- end delete modal -->
</tr>
<?php } ?>
</tbody>
</table>
<!-- end slider -->
</div>
</div>
</div>
<?php include('footer.php'); ?>
</div>
</div>
</div>
</body>
</html>
navhead_user.php
<div class="row-fluid">
<div class="span12">
<div class="navbar navbar-fixed-top navbar-inverse">
<div class="navbar-inner">
<div class="container">
<!-- .btn-navbar is used as the toggle for collapsed navbar content -->
<a class="btn btn-navbar" data-toggle="collapse" data-target=".nav-collapse">
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</a>
<!-- Be sure to leave the brand out there if you want it shown -->
<!-- Everything you want hidden at 940px or less, place within here -->
<div class="nav-collapse collapse">
<!-- .nav, .navbar-search, .navbar-form, etc -->
<i class="icon-facebook-sign icon-large" id="color_white"></i>
<i class="icon-twitter icon-large" id="color_white"></i>
<i class="icon-google-plus icon-large" id="color_white"></i>
<i class="icon-github-alt icon-large" id="color_white"></i>
<i class="icon-linkedin-sign icon-large" id="color_white"></i>
<div class="pull-right">
<form class="navbar-search pull-left">
<i class="icon-search icon-large" id="color_white"></i>
<input type="text" class="search-query" placeholder="Search">
</form>
</div>
<!-- end collapse -->
</div>
</div>
</div>
</div>
<div class="hero-unit-header">
<div class="container">
<div class="row-fluid">
<div class="span12">
<div class="row-fluid">
<div class="span6">
<img src="admin/images/head.png">
</div>
<div class="span6">
<div class="pull-right">
<!--- login button -->
<?php
$student_query=mysql_query("select * from teacher where teacher_id='$session_id'")or die(mysql_error());
$teacher_row= mysql_fetch_array($student_query);
?>
<img src="admin/<?php echo $teacher_row['location']; ?>" class="img img-rounded" id="picture">
<div class="btn-group">
<button class="btn btn-success"><i class="icon-user icon-large"></i> <?php echo $user_row['firstname'] . " " . $user_row['lastname']; ?></button>
<button class="btn dropdown-toggle" data-toggle="dropdown">
<span class="caret"></span>
</button>
<ul class="dropdown-menu">
<li><a href="#logout" role="button" data-toggle="modal"><i class="icon-signout icon-large"></i> Logout</a></li>
</ul>
</div>
<?php include('logout_modal.php') ?>
</div>
</div>
</div>
</div>
</div>
</div>
</div>