Filter/FilterBuilderUpdater.php
protected function prepareFilterValues(FormInterface $form)
    {
        $config = $form->getConfig();
        $values = $this->dataExtractor->extractData($form, $config->getOption('data_extraction_method', 'default'));

        if ($config->hasAttribute('filter_options')) {
            $values = array_merge($values, $config->getAttribute('filter_options'));
        }

        return $values;
    }
protected function prepareFilterValues(FormInterface $form)
    {
        $config = $form->getConfig();
        $values = $this->dataExtractor->extractData($form, $config->getOption('data_extraction_method', 'default'));

        if ($config->hasAttribute('filter_options')) {
            $values = array_merge($values, $config->getAttribute('filter_options'));
        }

        return $values;
    }
protected function prepareFilterValues ( FormInterface $ form ) { $ config = $ form -> getConfig ( ) ; $ values = $ this -> dataExtractor -> extractData ( $ form , $ config -> getOption ( 'data_extraction_method' , 'default' ) ) ; if ( $ config -> hasAttribute ( 'filter_options' ) ) { $ values = array_merge ( $ values , $ config -> getAttribute ( 'filter_options' ) ) ; } return $ values ; }
Prepare all values needed to apply the filter

@param  FormInterface $form
@return array
Prepare all values needed to apply the filter