Que dropdownlist no se cambie solo

International Spanish
1

Estoy creando un dropdownlist dependiente y funciona correctamente, lo que deseo es que el segundo select no se cambien automáticamente a los valores que debe traer sino que quede en la ‘prompt’=>‘Selecionar…’

Modelo select 1

<?php $clientes=Clientes::find()->where(['idruta' => Yii::$app->user->identity->idruta])->all();
       $listData=ArrayHelper::map($clientes,'id','fullName');
       echo $form->field($model, 'idcliente')->widget(Select2::className(),   
    )->label('Cliente')->dropDownList(
            $listData,
            ['prompt'=>'Selecionar...',
             'onchange' => '
            $.post(
                "' . Url::toRoute('getoperations') . '", 
                {id: $(this).val()}, 
                function(res){
                    $("#requester").html(res);
                }
            );
        ',]);?>

modelo selet 2

<?= $form->field($model,'idventa')->widget(Select2::className(),   
        )->label('Venta')->dropDownList( [ ],
        [
        'prompt' => 'Selecionar...',
        'placeholder' => 'Selecionar..e.',
        'id' => 'requester',
        ]); ?>

Controller

public function actionGetoperations()
{
if ($id = Yii::$app->request->post('id')) {
    $operationPosts = \app\models\Clientes::find()
        ->where(['id' => $id])
        ->count();

    if ($operationPosts > 0) {
        $mjs1 = "Credito de ";
        $mjs2 = " Cuota de ";
        $operations = \app\models\Ventas::find()
            ->where(['idcliente' => $id])
            ->andwhere(['>=', 'saldo', 1])
            ->all();
        foreach ($operations as $operation)

            echo "<option value='" . $operation->id. "'>" .$mjs1. $operation->valor .$mjs2. $operation->cuotas . "</option>";
    } else
        echo "<option>-</option>";

}
}

Agradezco me ayuden!!!

2

/* Moved to International/Spanish */

3

cambie el código del controlador con uno que me ayudaron en otro foro, lo publico por si a alguien le sirve

public function actionGetoperations() {
if ($id = Yii::$app->request->post('id')) {
    $operationPosts = \app\models\Clientes::find()
            ->where(['id' => $id])
            ->count();

    if ($operationPosts > 0) {
        $mjs1 = "Credito de ";
        $mjs2 = " Cuota de ";
        $operations = \app\models\Ventas::find()
                ->where(['idcliente' => $id])
                ->andwhere(['>=', 'saldo', 1])
                ->all();
        echo "<option value='' selected>Selecionar Venta</option>"; //Add your option at first... it will show at first instead first value of the option 
        foreach ($operations as $operation) {
            echo "<option value='" . $operation->id . "'>" . $mjs1 . $operation->valor . $mjs2 . $operation->cuotas . "</option>";
        }
    } else
        echo "<option>-</option>";
}
}