Include helper class in view - yii2

Question

I am working on a requirement of where I have to include all common methods like pagination, etc. which were used in my views into all my views. For this purpose I thought helper file is useful and created helper file in common\helpers\ directory with name Common as helper file name. I am facing difficulty in using this helper file in my view file.
I have included this helper file in my view as
use common\helpers\Common;
When I open the page I am getting error as "Class 'common\helpers\Common' not found"
My helper file: Common.php
namespace common\helpers;
class Common
{
protected $_file;
protected $_data = array();
public function __construct($file)
{
$this->_file = $file;
}
public static function getCommonHtml($id=NULL)
{
----
----
}
-----
--- Some other methods---
-----
}
I googled for this & got few solutions but they never worked.

Answer 1

You need to declare your new namespace in your composer.json:
"autoload": {
"psr-4": {
...
"common\\": "common/"
}
},
And the run:
composer dump-autoload
Alternatively you could declare alias for new namespace, so Yii autoloader will handle it (like in advanced template):
Yii::setAlias('#common', dirname(__DIR__))
But Yii autoloader will be dropped in Yii 2.1, so I would stick to composer-way (or do both - alias may be useful not only for autoloading).