Prado\Web\UI\WebControls\TDataBoundControl::determineDataSource PHP Method

    protected function determineDataSource()
    {
        if (!$this->_currentDataSourceValid) {
            if (($dsid = $this->getDataSourceID()) !== '') {
                if (($dataSource = $this->getNamingContainer()->findControl($dsid)) === null) {
                    throw new TInvalidDataValueException('databoundcontrol_datasourceid_inexistent', $dsid);
                } else {
                    if (!$dataSource instanceof IDataSource) {
                        throw new TInvalidDataValueException('databoundcontrol_datasourceid_invalid', $dsid);
                    } else {
                        $this->_currentDataSource = $dataSource;
                    }
                }
            } else {
                if (($dataSource = $this->getDataSource()) !== null) {
                    $this->_currentDataSource = new TReadOnlyDataSource($dataSource, $this->getDataMember());
                } else {
                    $this->_currentDataSource = null;
                }
            }
            $this->_currentDataSourceValid = true;
        }
        return $this->_currentDataSource;
    }