/**
     * Outputs the contents of a specific column.
     *
     * @since  4.6.0
     * @param  string $column The column-key (defined in post_columns above).
     * @param  int $post_id The ID of the popup.
     */
    public static function post_column_content($column, $post_id)
    {
        $popup = IncPopupDatabase::get($post_id);
        switch ($column) {
            case 'po_name':
                $can_edit = current_user_can('edit_post', $post_id) && 'trash' !== $popup->status;
                $post_type_object = get_post_type_object(IncPopupItem::POST_TYPE);
                $actions = array();
                if ($can_edit) {
                    $actions['edit'] = array('url' => get_edit_post_link($post_id), 'title' => __('Edit this PopUp', PO_LANG), 'attr' => '', 'label' => __('Edit', PO_LANG));
                }
                if ($can_edit && 'active' === $popup->status) {
                    $the_url = 'edit.php?post_type=%1$s&post_id=%2$s&action=deactivate';
                    $the_url = admin_url(sprintf($the_url, IncPopupItem::POST_TYPE, $post_id));
                    $the_url = wp_nonce_url($the_url, 'deactivate-post_' . $post_id);
                    $actions['deactivate'] = array('url' => $the_url, 'title' => __('Deactivate this PopUp', PO_LANG), 'attr' => '', 'label' => __('Deactivate', PO_LANG));
                }
                if ($can_edit && 'inactive' === $popup->status) {
                    $the_url = 'edit.php?post_type=%1$s&post_id=%2$s&action=activate';
                    $the_url = admin_url(sprintf($the_url, IncPopupItem::POST_TYPE, $post_id));
                    $the_url = wp_nonce_url($the_url, 'activate-post_' . $post_id);
                    $actions['activate'] = array('url' => $the_url, 'title' => __('Activate this PopUp', PO_LANG), 'attr' => '', 'label' => __('Activate', PO_LANG));
                }
                $actions['popup_preview'] = array('url' => '#', 'title' => __('Preview this PopUp', PO_LANG), 'attr' => 'class="po-preview" data-id="' . $post_id . '"', 'label' => __('Preview', PO_LANG));
                if (current_user_can('delete_post', $post_id)) {
                    if ('trash' === $popup->status) {
                        $the_url = $post_type_object->_edit_link . '&action=untrash';
                        $the_url = admin_url(sprintf($the_url, $post_id));
                        $the_url = wp_nonce_url($the_url, 'untrash-post_' . $post_id);
                        $actions['untrash'] = array('url' => $the_url, 'title' => __('Restore this PopUp from the Trash', PO_LANG), 'attr' => '', 'label' => __('Restore', PO_LANG));
                    } elseif (EMPTY_TRASH_DAYS) {
                        $actions['trash'] = array('url' => get_delete_post_link($post_id), 'title' => __('Move this PopUp to the Trash', PO_LANG), 'attr' => 'class="submitdelete"', 'label' => __('Trash', PO_LANG));
                    }
                    if ('trash' === $popup->status || !EMPTY_TRASH_DAYS) {
                        $actions['delete'] = array('url' => get_delete_post_link($post_id, '', true), 'title' => __('Delete this PopUp permanently', PO_LANG), 'attr' => 'class="submitdelete"', 'label' => __('Delete Permanently', PO_LANG));
                    }
                }
                if ($can_edit) {
                    ?>
					<a href="<?php 
                    echo esc_url(get_edit_post_link($post_id));
                    ?>
"
						title="<?php 
                    _e('Edit this PopUp', PO_LANG);
                    ?>
">
						<span class="the-title"><?php 
                    echo esc_html($popup->name);
                    ?>
</span>
					</a>
				<?php 
                } else {
                    ?>
					<span class="the-title"><?php 
                    echo esc_html($popup->name);
                    ?>
</span>
				<?php 
                }
                ?>
				<div class="row-actions">
				<?php 
                $action_count = count($actions);
                $i = 0;
                foreach ($actions as $action => $item) {
                    $i += 1;
                    $sep = $i == $action_count ? '' : ' | ';
                    ?>
					<span class="<?php 
                    echo esc_attr($action);
                    ?>
">
					<a href="<?php 
                    echo esc_url($item['url']);
                    ?>
"
						title="<?php 
                    echo esc_attr($item['title']);
                    ?>
"
						<?php 
                    echo '' . $item['attr'];
                    ?>
>
						<?php 
                    echo esc_html($item['label']);
                    ?>
					</a><?php 
                    echo esc_html($sep);
                    ?>
					</span>
					<?php 
                }
                ?>
				</div>
				<?php 
                break;
            case 'po_cond':
                $rule_count = 0;
                ?>
				<div class="rules">
				<?php 
                foreach ($popup->rule as $key) {
                    ?>
					<?php 
                    $label = IncPopupItem::condition_label($key);
                    ?>
					<?php 
                    if (empty($label)) {
                        continue;
                    }
                    ?>
					<?php 
                    $rule_count += 1;
                    ?>
					<span class="rule"><?php 
                    echo esc_html($label);
                    ?>
</span>
				<?php 
                }
                ?>
				<?php 
                if (!$rule_count) {
                    ?>
					<span class="rule-always"><?php 
                    _e('Always Show PopUp', PO_LANG);
                    ?>
</span>
				<?php 
                }
                ?>
				</div>
				<?php 
                break;
            case 'po_pos':
                if ('trash' === $popup->status) {
                    echo '-';
                } else {
                    $order = $popup->order;
                    if (!is_numeric($order) || $order > 999999) {
                        $order = '';
                    }
                    ?>
					<span class="the-pos"><?php 
                    echo esc_html($order);
                    ?>
</span>
					<?php 
                }
                break;
            case 'po_state':
                $title = $popup->status_label($popup->status);
                ?>
				<span title="<?php 
                echo esc_attr($title);
                ?>
">
					<i class="status-icon dashicons"></i>
				</span>
				<?php 
                break;
        }
    }