Joomla 3.x set User to a specific group with PHP - php

Question

I just want to set a user to a specific group. I have tried many things but not helped. One solutiuon is worked for me, but I think it is deprecated because in the Joomla's admin page I see other groups.
My code:
define( '_JEXEC', 1 );
define( 'DS', DIRECTORY_SEPARATOR );
define( 'JPATH_BASE', $_SERVER[ 'DOCUMENT_ROOT' ] );
require_once( JPATH_BASE . DS . 'includes' . DS . 'defines.php' );
require_once( JPATH_BASE . DS . 'includes' . DS . 'framework.php' );
require_once( JPATH_BASE . DS . 'libraries' . DS . 'joomla' . DS . 'factory.php' );
$user =JFactory::getUser(joe); //joe is the username
$GroupJoomla = array('14'=>14); //I want to change it's group to 14
$user->set('groups',$GroupJoomla); //Method one, which I have found on documentations
print_r ( $user->get('groups')); //Succesfully sets, BUT if I check on the Joomla's admin page, the user is still on other group. Maybe this is a deprecated function and the Joomla didnt use it now.
$user->groups = $GroupJoomla;
$user->save(); //Method two. Unfortunatelly this is always returns to false for me, dont know why. There is no error message. (Apache error log also empty)
print_r ($user->getAuthorisedGroups()); //This is the good to get the user's groups. This is correct.
if ($user->save() === false)
{
throw new Exception($user->getError(), 500); // This gives me this error: Error displaying the error page: Application Instantiation Error: Application Instantiation Error
}
What am I doing wrong? :/
I havent got Joomfish, so it isnt why the $user->save() returns false.
Update:
This code is also returns false on $user->save().
$uid = 1748;
$user =JFactory::getUser($uid); //joe is the username
$GroupJoomla = array(14); //I want to change it's group to 14
$user->set('groups',$GroupJoomla);
$user->groups = $GroupJoomla;
$user->save();
jimport( 'joomla.access.access' );//Call the Access Class
/*If the below code is not there it wont save.*/
if ($user->save() === false){ //This is gives me false somehow
throw new Exception($user->getError(), 500);
}
$groups = JAccess::getGroupsByUser($uid, false);
print_r($groups); exit; //Receives Group id 15 (Not 14)
With both code samples I have got the good user object. $user->get('username'); This gives me the good username. (Joomla 3.6.5)

Answer 1

As #itoctopus said you need to enter id instead of username but also there are some other mistakes that needs to be taken care of like initiating the group variable. It should be
$GroupJoomla = array(14);
if more than one group
$GroupJoomla = array(13,14);
then to get the groups you can use
$groups = JAccess::getGroupsByUser($id, false);
So finally your code will be
<?php
define( '_JEXEC', 1 );
define( 'DS', DIRECTORY_SEPARATOR );
define( 'JPATH_BASE', 'C:\xampp\htdocs\joomla' );
require_once( JPATH_BASE . DS . 'includes' . DS . 'defines.php' );
require_once( JPATH_BASE . DS . 'includes' . DS . 'framework.php' );
require_once( JPATH_BASE . DS . 'libraries' . DS . 'joomla' . DS . 'factory.php' );
$uid = 404;
$user =JFactory::getUser($uid); //joe is the username
$GroupJoomla = array(4,6); //I want to change it's group to 14
$user->set('groups',$GroupJoomla);
$user->groups = $GroupJoomla;
$user->save();
jimport( 'joomla.access.access' );//Call the Access Class
/*If the below code is not there it wont save.*/
if ($user->save() === false){
throw new Exception($user->getError(), 500);
}
$groups = JAccess::getGroupsByUser($uid, false);
print_r($groups); exit;

Answer 2

A quick glimpse at your code, and I think this line:
$user =JFactory::getUser(joe);
Should be:
$user =JFactory::getUser(5);
Where 5 is the id of the user with username "joe". You cannot get a user by username by using the function JFactory::getUser.
Alternatively, if you really want to get a user by username, then you should use:
$userId = JUserHelper::getUserId('joe'); //note that there are quotes around joe (in your code you omitted the quote)
$user =JFactory::getUser($userId);
Hope this helps.