Hi there,
I am developing front end filters for icagenda events component,i need to populate state in IcagendaModelList like this

protected function populateState($ordering = null, $direction = null)
{
// Initialise variables.
$app = JFactory::getApplication();

// Load the filter state.
$state = $app->getUserStateFromRequest($this->context.'.filter.city', 'filter_city', '', 'string');
$this->setState('filter.city', $state);
parent::populateState('e.title', 'asc');
}

please suggest me how to do this and where to do this.

Thanks in Advance.