--- /dev/null
+<?php
+
+namespace Drupal\environment_indicator;
+
+use Drupal\Core\Config\Entity\ConfigEntityListBuilder;
+use Drupal\Core\Entity\EntityInterface;
+
+/**
+ * Provides a listing of environments.
+ */
+class EnvironmentIndicatorListBuilder extends ConfigEntityListBuilder {
+
+ /**
+ * {@inheritdoc}
+ */
+ public function getFormID() {
+ return 'environment_indicator_overview_environments';
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function buildHeader() {
+ $row['name'] = $this->t('Environment name');
+ $row['url'] = $this->t('Environment url');
+ $row += parent::buildHeader();
+ return $row;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function buildRow(EntityInterface $entity) {
+ /* @var \Drupal\environment_indicator\Entity\EnvironmentIndicator $entity */
+ $row = [
+ 'style' => 'color: ' . $entity->getFgColor() . '; background-color: ' . $entity->getBgColor() . ';',
+ ];
+
+ $row['data']['name'] = [
+ 'data' => $entity->label(),
+ ];
+ $row['data']['url'] = [
+ 'data' => $entity->getUrl(),
+ ];
+
+ $row['data'] += parent::buildRow($entity);
+ return $row;
+ }
+
+ /**
+ * {@inheritdoc}
+ */
+ public function render() {
+ $build['action_header']['#markup'] = '<h3>' . t('Available actions:') . '</h3>';
+ $entities = $this->load();
+ // If there are not multiple vocabularies, disable dragging by unsetting the
+ // weight key.
+ if (count($entities) <= 1) {
+ unset($this->weightKey);
+ }
+ $build = parent::render();
+ $build['table']['#empty'] = $this->t('No environment switchers available. <a href=":link">Add environment</a>.', [':link' => \Drupal::url('entity.environment_indicator.add')]);
+ return $build;
+ }
+
+}