Added block for adding activities

src/Plugin/Block/AddActivity.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace Drupal\opencase\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+
+/**
+ * Provides a Block with some help text about actor type fields
+ *
+ * @Block(
+ *   id = "add_activity",
+ *   admin_label = @Translation("Add Activity"),
+ *   category = @Translation("Opencase"),
+ * )
+ */
+class AddActivity extends BlockBase {
+
+    /**
+     * {@inheritdoc}
+     */
+    public function build():array {
+        $target_id = \Drupal::routeMatch()->getParameter('oc_actor')->id();
+        $activity_types = \Drupal::service('entity_type.bundle.info')->getBundleInfo('oc_activity');
+        $markup = "<ul>";
+        foreach($activity_types as $id => $info) {
+            $label = $info['label'];
+            $markup .= "<li><a href='/opencase/oc_activity/add/$id?target_id=$target_id&destination=/opencase/oc_actor/$target_id'>$label</a></li>";
+        }
+        $markup .= "</ul>";
+        return array('#markup' => $markup);
+    }
+
+    public function getCacheMaxAge():int {
+        return 0;
+    }
+
+}