frameworks - How to use models from models/ in layouts/main.php in yii 2.0 (basic template) -

i have started learn yii framework day ago , came problem.

i have downloaded basic application template (so know structure of application).

i use 1 of classes's function "models/" in "views/layouts/main.php", however, not sure how can access them "main.php". have searched around internet , none of solutions have helped me.

1. i've read widget creation, can use in "main.php" in link - yii - how retrieve model data layout page?, not provide version of yii coulnt not find protected folder , etc. kind of confused.
2. also read other solution, did not me well.

what suggest me do? because have no clue solution. newbiew in framework, so, don't judge me hard :)

updated: [solution]

// use statement on top of main.php other use statements use app\models\modelname;   // anywhere in file ....  $mymodel = new modelname;  $mymodel->myfunction(); ...   // or if static function:  modelname::myfunction(); 

this how access model files (classes) folder models/ example views/layouts/main.php.

here deal - view "view". view should represent data, not data. don't want have logic in view.

anyway, if want show model - should pass model through controller, renders view.

controller like:

$model = new device; $this->render('index', array(     'model' => $model )); 

then can use in view, data model.

you directly in view, not practice.

here can read basics models , best practices how use them.

update [yii 1.x]
use model-class in main.php, import @ place want use it:

     yii::import('application.models.loginform'); 

after can use functions model class.

update 2
namespaces in yii2:

use yii\models\loginform; 

at start of main.php layout-file. @ "layouts" part here.