Yii2 Kartik Select2 - Template to formatting each list element - yii2

Question

i'm looking to Kartik Select2 Page
In particular i want to add an image to each element of the list like the example:
use kartik\widgets\Select2;
use yii\web\JsExpression;
use yii\bootstrap\Modal;
// Templating example of formatting each list element
$url = \Yii::$app->urlManager->baseUrl . '/images/flags/';
$format = <<< SCRIPT
function format(state) {
if (!state.id) return state.text; // optgroup
src = '$url' + state.id.toLowerCase() + '.png'
return '<img class="flag" src="' + src + '"/>' + state.text;
}
SCRIPT;
$escape = new JsExpression("function(m) { return m; }");
$this->registerJs($format, View::POS_HEAD);
echo '<label class="control-label">Provinces</label>';
echo Select2::widget([
'name' => 'state_12',
'data' => $data,
'options' => ['placeholder' => 'Select a state ...'],
'pluginOptions' => [
'templateResult' => new JsExpression('format'),
'templateSelection' => new JsExpression('format'),
'escapeMarkup' => $escape,
'allowClear' => true
],
]);
In this example as you can see, the filename with the image of the state has the same name of the state.id
src = '$url' + state.id.toLowerCase() + '.png'
and it's simple to use.
But my problem is that the filename for each state is different and is stored in my db. For example i have:
//Active Record
$state->id //my state id
$state->img // the name of the image i want
How can i pass the right image name for each element of the list to the script?
Thank's for any help.