This is my view
'promoter_id' => [ 
    'type' => Form::INPUT_DROPDOWN_LIST,
    'options' => ['prompt' => '--'.Yii::t ( 'app', 'Ventor Type' ).'--',],
    'items' => ArrayHelper::map (
        User::find ()->orderBy ( 'username')->where(['user_type_id' => [13]])->asArray ()->all (),
        'id', 
        'username' 
    )
]
What i did?
show the users filtered by user_type_id = 13.
user_type_id=13 means the users are promoters.
What i want?
I want to show the users like below sql query using ArrayHelper::map.
SELECT u.username 
    FROM tbl_user u,tbl_user_type t
    where u.user_type_id = t.id and t.type='promoter';
				
                        
Since you are using mysql you can simply use an
innerJoin:If you have a relation between
useranduser_typeyou can usejoinWithinstead, which handles the join type and the join condition for you: