public function getColumnSettings()
    {
        if (is_null($this->_columnSettings)) {
            $this->_columnSettings = [];
            foreach ($this->columns as $key => $c) {
                if (!$c->visible) {
                    continue;
                }
                $this->_columnSettings[$key] = ['label' => $c->getDataLabel()];

                if (!isset($c->htmlOptions)) {
                    $c->htmlOptions = [];
                }
                $this->_columnSettings[$key]['htmlOptions'] = $c->htmlOptions;
                $sortableResolve = $this->dataProvider->sort->resolveAttribute($c->name);
                $this->_columnSettings[$key]['sortable'] = !empty($sortableResolve);
            }
        }

        return $this->_columnSettings;
    }