Дмитрий

echo FileInput::widget([
            'name'          => 'attachment_' . $id,
            'options'       => [
                'multiple' => true
            ],
            'pluginOptions' => [
                'minFileCount' => 1,
                'required' => true,
                'deleteUrl'            => Url::to(['ajax-cars/del-img-moderator']),
                'initialPreview'       => $initialPreview,
                'initialPreviewConfig' => $caption,
                'initialPreviewAsData' => true,
                'showCaption'          => false,
                'showBrowse'           => false,
                'showRemove'           => false,
                'showUpload'           => false,
                'initialCaption'       => "The Moon and the Earth",
                'overwriteInitial'     => false,
                'fileActionSettings'   => [
                    'showDrag' => false,
                    'showZoom' => false
                ]
            ]
        ])

'initialPreview'       => $initialPreview,
'initialPreviewConfig' => $caption,

$initialPreview = [];
$caption        = [];

foreach ($images as $image) {
     $initialPreview[] = Url::toRoute($image->path . DIRECTORY_SEPARATOR . 'mini' . DIRECTORY_SEPARATOR . $image->title, true);
     $caption[]        = [
           'key'   => $image->id,
           'extra' => [
               'img' => [
                    'big'   => $image->path . DIRECTORY_SEPARATOR . $image->title,
                    'small' => $image->path . DIRECTORY_SEPARATOR . 'mini' . DIRECTORY_SEPARATOR . $image->title
                ]
           ]
     ];
}

$this->registerJs('
  var input = $("#uploadsfiles-imagesfile");
  $("#uploadsfiles-imagesfile").on("filebatchselected", function(){
      input.fileinput("upload")
  })
  
  var OtherActionButtons = "<button class=\"set-main btn btn-sm btn-kv btn-default btn-outline-secondary\" type=\"button\" {dataKey} title=\"Main photo\">";
      OtherActionButtons += "<i class=\"fa fa-star\"></i>";
      OtherActionButtons += "</button>";
      OtherActionButtons += "<button class=\"set-main btn btn-sm btn-kv btn-default btn-outline-secondary\" type=\"button\" {dataKey} title=\"Left\">";
      OtherActionButtons += "<i class=\"fa fa-undo\"></i>";
      OtherActionButtons += "</button>";
      OtherActionButtons += "<button class=\"set-main btn btn-sm btn-kv btn-default btn-outline-secondary\" type=\"button\" {dataKey} title=\"Right\">";
      OtherActionButtons += "<i class=\"fa fa-repeat\"></i>";
      OtherActionButtons += "</button>";
     
/*  $(".btn-submit").on("click", function(){
      var Text = $(".file-caption-name").val();
      input.fileinput("upload");
      if(Text == ""){
        return false;
      }  
  })   */
    
  var funCi = $("#uploadsfiles-imagesfile").on("fileuploaded", function(event, data, previewId, index) {
  input.fileinput("destroy").fileinput({
    maxFileCount: 2,
    validateInitialCount: true,
    overwriteInitial: false,
    required: true,
    multiple: true,
    /*showUpload: false,
    showRemove: false,*/
    initialPreviewAsData: true,
    initialPreview: data.response.initialPreview,
    initialPreviewConfig: data.response.initialPreviewData,
    otherActionButtons: OtherActionButtons,
    uploadUrl: "' . Url::to(['upload-img']) . '",
    deleteUrl: "' . Url::to(['delete-img']) . '",
  })
  // setTimeout(function(){funCi}, 2500)
  input.closest("form").find("button").attr("disabled", false)
    console.log(data);
});
', View::POS_END);

'rules' => [
  // если main у Вас контролер, а search действие
  '' => 'main/index',
 '<_a:(search)>/<request:\w+>' => 'main/search'
]

$query = Profile::find()
   /* получаем все поля из таблицы профиля и считаем записи в таблице полисов */
   ->select(['{{%profile}}.*', 'count' => 'COUNT({{%policy}}.id)'])
   /* подгружаем "не жадно" необходимые данные через связь getPolicy() */
  ->joinWith('policy', false)
 /* группируем записи по id профиля */
  ->groupBy('{{%profile}}.id')
/* сортируем по количеству проданных полисов в порядке убывания */
  ->orderBy(['count' => SORT_DESC]);

$dataProvider = new ActiveDataProvider([
   'query' => $query
]);

public function init()
    {
        $this->sourcePath = __DIR__ . '/assets';
        parent::init();
    }

assets /* js and css */
view /* view widget */
ModalWidget.php
ModalAssets.php

public $js = [
   '/js/modal.js'
]

query = Yii::$app->db->createCommand("SELECT *, DATE_FORMAT(".Cars::tableName().".car_created_date,'%m') as mouth From `cars` WHERE `status` = 3 LIMIT 2")->queryAll();

Если провожу поиск, то контроллер закономерно ругается, что отсутствуют обязательные параметры: course_id.

Есть ли возможно сделать админа без заморочек

'db' => [
   'class' => 'yii\db\Connection',
   'dsn' => 'mysql:host=localhost;dbname=fedorov_shop',
   'username' => 'fedorov_shop',
   'password' => '***',
   'charset' => 'utf8',
   'enableSchemaCache' => true,
   'schemaCacheDuration' => 3600,
]

public function init()
    {
        $this->db = 'db2';
        parent::init();
    }

public function init()
     {
         parent::init();
         Yii::$app->view->setAssetManager(new AssetManager());
     }