silverstripe-gridfieldextensions/code/GridFieldTitleHeader.php

<?php

use SilverStripe\Forms\GridField\GridField_HTMLProvider;
use SilverStripe\ORM\ArrayList;
use SilverStripe\View\ArrayData;

/**
 * A simple header which displays column titles.
 */
class GridFieldTitleHeader implements GridField_HTMLProvider {

	public function getHTMLFragments($grid) {
		$cols = new ArrayList();

		foreach ($grid->getColumns() as $name) {
			$meta = $grid->getColumnMetadata($name);

			$cols->push(new ArrayData(array(
				'Name'  => $name,
				'Title' => $meta['title']
			)));
		}

		return array(
			'header' => $cols->renderWith('GridFieldTitleHeader'),
		);
	}

}