Wrapping leaf nodes in non polymer elements

runtime/observatory/lib/src/elements/error_ref_wrapper.dart

+// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:html';
+
+import 'package:observatory/app.dart';
+import 'package:observatory/mocks.dart' show ErrorRefMock;
+import 'package:observatory/service_html.dart' show ServiceMap, DartError;
+import 'package:observatory/src/elements/error_ref.dart';
+import 'package:observatory/src/elements/helpers/tag.dart';
+import 'package:observatory/src/elements/shims/binding.dart';
+
+class ErrorRefElementWrapper extends HtmlElement {
+
+  static final binder = new Binder<ErrorRefElementWrapper>(
+    const [const Binding('ref')]);
+
+  static const tag = const Tag<ErrorRefElementWrapper>('error-ref');
+
+  ServiceMap _error;
+  ServiceMap get ref => _error;
+  void set ref(ServiceMap ref) { _error = ref; render(); }
+
+  ErrorRefElementWrapper.created() : super.created() {
+    binder.registerCallback(this);
+    createShadowRoot();
+    render();
+  }
+
+  @override
+  void attached() {
+    super.attached();
+    render();
+  }
+
+  void render() {
+    shadowRoot.children = [];
+    if (_error == null) return;
+
+    if (ref is Map) {
+      shadowRoot.children = [
+        new StyleElement()
+          ..text = '@import "packages/observatory/src/elements/css/shared.css";',
+        new ErrorRefElement(new ErrorRefMock(message: ref['message']))
+      ];
+    } else {
+      shadowRoot.children = [
+        new StyleElement()
+          ..text = '@import "packages/observatory/src/elements/css/shared.css";',
+        new ErrorRefElement(
+                        new ErrorRefMock(message: (ref as DartError).message),
+                        queue: ObservatoryApplication.app.queue)
+      ];
+    }
+  }
+}