[BEAM-13619] [Playground] Add loading animation to the catalog

playground/frontend/lib/components/loading_indicator/loading_indicator.dart

@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import 'package:flutter/material.dart';
+import 'package:playground/constants/colors.dart';
+
+class LoadingIndicator extends StatelessWidget {
+  final double size;
+
+  const LoadingIndicator({Key? key, required this.size}) : super(key: key);
+
+  @override
+  Widget build(BuildContext context) {
+    return Center(
+      child: SizedBox(
+        height: size,
+        width: size,
+        child: const CircularProgressIndicator(
+          color: kLightPrimary,
+        ),
+      ),
+    );
+  }
+}

playground/frontend/lib/modules/editor/repository/code_repository/code_repository.dart

@@ -166,6 +166,7 @@ class CodeRepository {
         final log = responses[1];
         final error = responses[2];
         return RunCodeResult(
+          pipelineUuid: pipelineUuid,
           status: status,
           output: prevOutput + output.output + error.output,
           log: prevLog + log.output,

playground/frontend/lib/modules/examples/example_selector.dart

@@ -17,6 +17,7 @@
  */
 
 import 'package:flutter/material.dart';
+import 'package:playground/components/loading_indicator/loading_indicator.dart';
 import 'package:playground/config/theme.dart';
 import 'package:playground/constants/sizes.dart';
 import 'package:playground/modules/examples/components/examples_components.dart';
@@ -151,18 +152,10 @@ class _ExampleSelectorState extends State<ExampleSelector>
                           color: Theme.of(context).backgroundColor,
                           borderRadius: BorderRadius.circular(kMdBorderRadius),
                         ),
-                        child: Column(
-                          children: [
-                            SearchField(controller: textController),
-                            const TypeFilter(),
-                            ExampleList(
-                              controller: scrollController,
-                              selectedExample: playgroundState.selectedExample!,
-                              animationController: animationController,
-                              dropdown: examplesDropdown,
-                            ),
-                          ],
-                        ),
+                        child: exampleState.sdkCategories == null ||
+                                playgroundState.selectedExample == null
+                            ? const LoadingIndicator(size: kContainerHeight)
+                            : _buildDropdownContent(playgroundState),
                       ),
                     ),
                   ),
@@ -175,6 +168,21 @@ class _ExampleSelectorState extends State<ExampleSelector>
     );
   }
 
+  Widget _buildDropdownContent(PlaygroundState playgroundState) {
+    return Column(
+      children: [
+        SearchField(controller: textController),
+        const TypeFilter(),
+        ExampleList(
+          controller: scrollController,
+          selectedExample: playgroundState.selectedExample!,
+          animationController: animationController,
+          dropdown: examplesDropdown,
+        ),
+      ],
+    );
+  }
+
   SelectorPositionModel findSelectorPositionData() {
     RenderBox? rBox =
         selectorKey.currentContext?.findRenderObject() as RenderBox;