aMember (site.php): extend standard filter for payments grid

site.php

<?php

Am_Di::getInstance()->hook->add('gridPaymentInitGrid', function(Am_Event_Grid $e) {
   $e->getGrid()->setFilter(new Am_Grid_Filter_PaymentsAdv);
});

class Am_Grid_Filter_PaymentsAdv extends Am_Grid_Filter_Payments
{
    public function renderInputs()
    {
        return parent::renderInputs()
            . $this->renderCheckbox('only_recurring', ___('display only recurring'))
            . $this->renderCheckbox('only_not_recurring', ___('display only not recurring'));
    }

    public function renderCheckbox($name, $title)
    {
        return sprintf(<<<CUT
            <label>
                <input type="hidden" name="%s_filter[$name]" value="0" />
                <input type="checkbox" name="%s_filter[$name]" value="1" %s /> %s</label>
CUT
            , $this->grid->getId()
            , $this->grid->getId()
            , (!empty($this->vars['filter'][$name]) ? 'checked' : '')
            , Am_Html::escape($title)
        );
    }

    protected function applyFilter()
    {
        parent::applyFilter();
        $filter = (array)$this->vars['filter'];
        if (!empty($filter['only_recurring'])) {
            $q = $this->grid->getDataSource()->getDataSourceQuery();
            if (!$this->isInvoiceJoin) {
                $q->leftJoin('?_invoice', 'i', 't.invoice_id=i.invoice_id');
                $this->isInvoiceJoin = true;
            }
            $q->addWhere('rebill_times>0');
        }
        if (!empty($filter['only_not_recurring'])) {
            $q = $this->grid->getDataSource()->getDataSourceQuery();
            if (!$this->isInvoiceJoin) {
                $q->leftJoin('?_invoice', 'i', 't.invoice_id=i.invoice_id');
                $this->isInvoiceJoin = true;
            }
            $q->addWhere('IFNULL(rebill_times,0) = 0');
        }
    }
}