protected function render_context_header(context_header $contextheader) {

        $showheader = empty($this->page->layout_options['nocontextheader']);
        if (!$showheader) {
            return '';
        }

        // All the html stuff goes here.
        $html = html_writer::start_div('page-context-header');

        // Image data.
        if (isset($contextheader->imagedata)) {
            // Header specific image.
            $html .= html_writer::div($contextheader->imagedata, 'page-header-image');
        }

        // Headings.
        if (!isset($contextheader->heading)) {
            $headings = $this->heading($this->page->heading, $contextheader->headinglevel);
        } else {
            $headings = $this->heading($contextheader->heading, $contextheader->headinglevel);
        }

        $html .= html_writer::tag('div', $headings, array('class' => 'page-header-headings'));

        // Buttons.
        if (isset($contextheader->additionalbuttons)) {
            $html .= html_writer::start_div('btn-group header-button-group');
            foreach ($contextheader->additionalbuttons as $button) {
                if (!isset($button->page)) {
                    // Include js for messaging.
                    if ($button['buttontype'] === 'togglecontact') {
                        \core_message\helper::togglecontact_requirejs();
                    }
                    if ($button['buttontype'] === 'message') {
                        \core_message\helper::messageuser_requirejs();
                    }
                    $image = $this->pix_icon($button['formattedimage'], $button['title'], 'moodle', array(
                        'class' => 'iconsmall',
                        'role' => 'presentation'
                    ));
                    $image .= html_writer::span($button['title'], 'header-button-title');
                } else {
                    $image = html_writer::empty_tag('img', array(
                        'src' => $button['formattedimage'],
                        'role' => 'presentation'
                    ));
                }
                $html .= html_writer::link($button['url'], html_writer::tag('span', $image), $button['linkattributes']);
            }
            $html .= html_writer::end_div();
        }
        $html .= html_writer::end_div();

        return $html;
    }