Custom PHP Mailer attachment not attached with email - php

Question

I have customize mailer function where except file attachment, rest of things are working well. To make it simplify, I have added only code related to attachment. As output, I can see file uploaded to server but it's going to attach in email. I am getting all details in email except file attachment. it's customize mailer class which I have created but not sure why attachment not sending to email.
Mailer.class.php
<?php
class Mailer
{
private $addAttachment = [];
public function addAttachment($addAttachment)
{
if (empty($addAttachment))
{
$this->setError('No Attachments','empty');
}else{
$this->addAttachment[] = $addAttachment;
echo $addAttachment;
}
return $this;
}
}
For Sending test.php
require_once 'Mailer.class.php';
$toemails = array("my_email_address#gmail.com");
$toemail = implode(',', $toemails);
if ($_SERVER["REQUEST_METHOD"] == "POST") {
$attachment = $_FILES["uploaded_file"]["tmp_name"];
$folder = '/uploads/';
$file_name1 = $_FILES["uploaded_file"]["name"];
move_uploaded_file($_FILES["uploaded_file"]["tmp_name"], "$folder".$_FILES["uploaded_file"]["name"]);
print_r($_FILES);
$mailer = new Mailer(true);
$mailer->setToEmail($toemail)
->setFromName(isset($_POST['fname'])?$_POST['fname']:'')
->setFromEmail(isset($_POST['email'])?$_POST['email']:'')
->setSubject('Application Regarding'.$_POST['Title'])
->addAttachment('/uploads/'.$_FILES["uploaded_file"]["name"])
->setBody($body)
->run();
exit();
if(!$mailer->sendMail()) {
echo "Something has gone wrong, please contact the site administrator or try again.";
}
else {
echo "Email Successfully Submitted";
}
print "</pre>";
}
?>
print_r($_FILES) gives me following Output for attachment:
Array
(
[uploaded_file] => Array
(
[name] => Image_Manager.pdf
[type] => application/pdf
[tmp_name] => /tmp/phplBV7gV
[error] => 0
[size] => 150300
)
)