Grid/Grid.php
public function isReadyForRedirect()
    {
        if ($this->source === null) {
            throw new \Exception(self::SOURCE_NOT_SETTED_EX_MSG);
        }

        if ($this->redirect !== null) {
            return $this->redirect;
        }

        $this->createHash();

        $this->requestData = (array) $this->request->get($this->hash);

        $this->processPersistence();

        $this->sessionData = (array) $this->session->get($this->hash);

        $this->processLazyParameters();

        // isReadyForRedirect ?
        if (!empty($this->requestData)) {
            $this->processRequestData();

            $this->redirect = true;
        }

        if ($this->redirect === null || ($this->request->isXmlHttpRequest() && !$this->isReadyForExport)) {
            if ($this->newSession) {
                $this->setDefaultSessionData();
            }

            $this->processPermanentFilters();

            //Configures the grid with the data read from the session.
            $this->processSessionData();

            $this->prepare();

            $this->redirect = false;
        }

        return $this->redirect;
    }
public function isReadyForRedirect()
    {
        if ($this->source === null) {
            throw new \Exception(self::SOURCE_NOT_SETTED_EX_MSG);
        }

        if ($this->redirect !== null) {
            return $this->redirect;
        }

        $this->createHash();

        $this->requestData = (array) $this->request->get($this->hash);

        $this->processPersistence();

        $this->sessionData = (array) $this->session->get($this->hash);

        $this->processLazyParameters();

        // isReadyForRedirect ?
        if (!empty($this->requestData)) {
            $this->processRequestData();

            $this->redirect = true;
        }

        if ($this->redirect === null || ($this->request->isXmlHttpRequest() && !$this->isReadyForExport)) {
            if ($this->newSession) {
                $this->setDefaultSessionData();
            }

            $this->processPermanentFilters();

            //Configures the grid with the data read from the session.
            $this->processSessionData();

            $this->prepare();

            $this->redirect = false;
        }

        return $this->redirect;
    }
Handle the grid redirection, export, etc..