private function _validateColumn(array $data)
    {
        if (!isset($data['label'])) {
            return 'Label key is required.';
        }
        if (!isset($data['index'])) {
            return 'Index key is required.';
        }

        if (isset($data['renderer']) && (!$data['renderer'] instanceof \Closure && !is_string($data['renderer']))) {
            return 'Renderer must be a string or instance of Closure object.';
        }

        if (isset($data['filter']) && !$data['filter'] instanceof \Closure) {
            return 'Filter function must be instance of Closure object.';
        }

        return true;
    }
private function _validateColumn(array $data)
    {
        if (!isset($data['label'])) {
            return 'Label key is required.';
        }
        if (!isset($data['index'])) {
            return 'Index key is required.';
        }

        if (isset($data['renderer']) && (!$data['renderer'] instanceof \Closure && !is_string($data['renderer']))) {
            return 'Renderer must be a string or instance of Closure object.';
        }

        if (isset($data['filter']) && !$data['filter'] instanceof \Closure) {
            return 'Filter function must be instance of Closure object.';
        }

        return true;
    }
private function _validateColumn ( array $ data ) { if ( ! isset ( $ data [ 'label' ] ) ) { return 'Label key is required.' ; } if ( ! isset ( $ data [ 'index' ] ) ) { return 'Index key is required.' ; } if ( isset ( $ data [ 'renderer' ] ) && ( ! $ data [ 'renderer' ] instanceof \ Closure && ! is_string ( $ data [ 'renderer' ] ) ) ) { return 'Renderer must be a string or instance of Closure object.' ; } if ( isset ( $ data [ 'filter' ] ) && ! $ data [ 'filter' ] instanceof \ Closure ) { return 'Filter function must be instance of Closure object.' ; } return true ; }
Checks if provided column data is valid
Returns bool if it's valid
Returns string it it's not valid

@param array $data
@return bool|string
Checks if provided column data is valid Returns bool if it s valid Returns string it it s not valid