Sonata admin bundle, how do not show any results and don't execute any query to DB if user don't select any filters?

Question

I have typical sonata-admin list action with createQuery, configureFormFields, etc . How i can render standard page but if user don't select any filters, i show him only "select any filter for getting results"?

I can use hasFilters checked but query still executed.

{% if  admin.hasFilters() %}
    {{ parent() }}
{% else %}

I need some just like that, but without execute any query to DB.

// SomeController
public function listAction()
{
    if (!$this->admin->hasFilters()) {
        return $this->renderWithExtraParams($this->admin->getTemplate('list'), [
            'action' => 'list',
            'form' => $this->admin->getDatagrid()->getForm()->createView(),
            'csrf_token' => $this->getCsrfToken('sonata.batch'),
            'export_formats' => $this->has('sonata.admin.admin_exporter') ?
                $this->get('sonata.admin.admin_exporter')->getAvailableFormats($this->admin) :
                $this->admin->getExportFormats(),
        ], null);
    }

    return parent::listAction();
}

Answer 1

This is kludge but it's working. Just add this:

public function createQuery($context = 'list')
{
    $query = parent::createQuery($context);

    if (!$this->hasFilters()) {
        $query->where('1 = 0');

        return $query;
    }

    // ...
}