Calling a element after login - cakephp

Question

I have a post index view calling a element which content input field for comment.
I call it in this way
<?php echo $this->element('addcomment', array('post_id' => $post['Post']['id'])); ?>
This work fine, I pass the post id parameter, in the addcomment element, because the post_id input field is hidden in the addcomment. and of course I dont want that the user type the post id.
I have set up the authorization mechanism in order to allow adding comment to the user identified (connected).
When a non-connected user try to add a comment, he receives the login screen.
After login, he is redirected to the add commment form. The problem is that in the mean time it loose the value of the post_id variable.
Rem: If the user is connected before adding comments to the post, it works.
Dont hesitate to contact me in case my explanation is not clear or if you need more information.
This is my addcomment element
<div class="Addcomment form">
<?php
echo $this->Form->create('Comment', array(
'url' => array('controller' => 'comments', 'action' => 'add')
)); ?>
<fieldset>
<legend><?php echo __('Add Comment'); ?></legend>
<?php if (isset($current_user['id']) && isset($post_id)): ?>
<?php $this->request->data['Comment']['user_id'] = $current_user['id']; ?>
<?php $this->request->data['Comment']['post_id'] = $post_id; ?>
<?php echo $this->Form->input('post_id', array('type' => 'hidden')); ?>
<?php echo $this->Form->input('user_id', array('type' => 'hidden')); ?>
<?php else: echo $this->Form->input('post_id'); ?>
<?php endif; ?>
<?php echo $this->Form->input('content', array('class' => 'comment')); ?>
</fieldset>
<?php echo $this->Form->end(__('Submit')); ?>
</div>

Answer 1

As per i understand your problem. You can use a session variable to store a post id which should not affected if user logs in. And using this session you can redirect a user to particular post after login.
Set a session value before redirecting user to login.
$this->Session->write('last_post_id',YOUR_POST_ID);
Redirect user to the post if user successfully logged in and if you find a session value not empty.
if ($this->Session->check('last_post_id') && $this->Session->read('last_post_id') != '') {
$this->redirect(YOUR_URL_TO_POST . '?postid=' . $this->Session->read('last_post_id'));
exit;
}else{
//NORMAL REDIRECTION
}
Hope this will help you. Unset session last_post_id after redirection and if no longer required.