Converted Observatory nav-bar element

runtime/observatory/lib/src/elements/nav/bar.dart

+// Copyright (c) 2016, 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 'dart:async';
+import 'package:observatory/src/elements/helpers/tag.dart';
+import 'package:observatory/src/elements/helpers/rendering_scheduler.dart';
+
+class NavBarElement extends HtmlElement implements Renderable {
+  static final StyleElement _style = () {
+      var style = new StyleElement();
+      style.text = 'nav.nav-bar {'
+                     'position: fixed;'
+                     'top: -56px;'
+                     'width: 100%;'
+                     'z-index: 1000;'
+                     '}'
+                   'nav.nav-bar > ul {'
+                     'display: inline-table;'
+                     'position: relative;'
+                     'list-style: none;'
+                     'padding-left: 0;'
+                     'margin-left: 0;'
+                     'width: 100%;'
+                     'z-index: 1000;'
+                     'font: 400 16px \'Montserrat\', sans-serif;'
+                     'color: white;'
+                     'background-color: #0489c3;'
+                   '}'
+                   'nav.nav-bar:after {'
+                     'content: ""; clear: both; display: block;'
+                   '}'
+                   'nav.nav-bar:before {'
+                     'height: 40px;'
+                     'background-color: #0489c3;'
+                     'content: ""; display: block;'
+                   '}';
+      return style;
+  }();
+
+  static const tag = const Tag<NavBarElement>('nav-bar');
+
+  RenderingScheduler _r;
+
+  Stream<RenderedEvent<NavBarElement>> get onRendered => _r.onRendered;
+
+  factory NavBarElement({RenderingQueue queue}) {
+    NavBarElement e = document.createElement(tag.name);
+    e._r = new RenderingScheduler(e, queue: queue);
+    return e;
+  }
+
+  NavBarElement.created() : super.created() {
+    // TODO(cbernaschina) remove when no more needed.
+    _r = new RenderingScheduler(this);
+    createShadowRoot();
+  }
+
+  @override
+  void attached() { super.attached(); _r.enable(); }
+
+  @override
+  void detached() {
+    super.detached(); _r.disable(notify: true);
+    shadowRoot.children = [];
+  }
+
+  void render() {
+    shadowRoot.children = [
+      _style.clone(true),
+      document.createElement('nav')
+        ..classes = ['nav-bar']
+        ..children = [
+          new UListElement()
+            ..children = [
+              new ContentElement()
+            ],
+        ],
+      new DivElement()
+    ];
+  }
+}