Wrapping leaf nodes in non polymer elements

runtime/observatory/lib/src/elements/nav/notify_exception.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';
+import 'package:observatory/models.dart'
+  show ConnectionException;
+
+
+class ExceptionRemoveEvent{
+  final Exception exception;
+  final StackTrace stacktrace;
+
+  ExceptionRemoveEvent(this.exception, {this.stacktrace});
+}
+
+class NavNotifyExceptionElement extends HtmlElement implements Renderable {
+  static const tag = const Tag<NavNotifyExceptionElement>('nav-exception');
+
+  RenderingScheduler _r;
+
+  Stream<RenderedEvent<NavNotifyExceptionElement>> get onRendered =>
+                                                                  _r.onRendered;
+
+  final StreamController<ExceptionRemoveEvent> _onRemove;
+  final Stream<ExceptionRemoveEvent> onRemove;
+
+  Exception _exception;
+  StackTrace _stacktrace;
+  Exception get exception => _exception;
+  StackTrace get stacktrace => _stacktrace;
+
+  factory NavNotifyExceptionElement(Exception exception,
+                              {StackTrace stacktrace: null,
+                               RenderingQueue queue}) {
+    assert(exception != null);
+    NavNotifyExceptionElement e = document.createElement(tag.name);
+    e._r = new RenderingScheduler(e, queue: queue);
+    e._exception = exception;
+    e._stacktrace = stacktrace;
+    return e;
+  }
+
+  NavNotifyExceptionElement.created()
+    : this._(new StreamController<ExceptionRemoveEvent>());
+
+  NavNotifyExceptionElement._(StreamController<ExceptionRemoveEvent> onRemove)
+    : super.created(),
+      this._onRemove = onRemove,
+      this.onRemove = onRemove.stream.asBroadcastStream();
+
+  @override
+  void attached() { super.attached(); _r.enable(); }
+
+  @override
+  void detached() { super.detached(); children = []; _r.disable(notify: true); }
+
+  void render() {
+    if (exception is ConnectionException) {
+      renderConnectionException();
+    } else {
+      renderGenericException();
+    }
+  }
+
+  void renderConnectionException() {
+    children = [
+      new DivElement()
+        ..children = [
+        new SpanElement()..text = 'The request cannot be completed because the '
+                                  'VM is currently disconnected',
+        new BRElement(), new BRElement(),
+        new SpanElement()..text = '[',
+        new AnchorElement(href: '#/vm-connect')
+          ..text = 'Connect to a different VM',
+        new SpanElement()..text = ']',
+        new ButtonElement()..innerHtml = '&times;'
+          ..onClick.map(_toEvent).listen(_remove)
+      ]
+    ];
+  }
+
+  void renderGenericException() {
+    List<Node> content;
+    content = [
+      new SpanElement()..text = 'Unexpected exception:',
+      new BRElement(), new BRElement(),
+      new DivElement()..text = exception.toString(),
+      new BRElement()
+    ];
+    if (stacktrace != null) {
+      content.addAll([
+        new SpanElement()..text = 'Stacktrace:',
+        new BRElement(), new BRElement(),
+        new DivElement()..text = stacktrace.toString(),
+        new BRElement()
+      ]);
+    }
+    content.addAll([
+      new SpanElement()..text = '[',
+      new AnchorElement(href: '#/vm-connect')
+        ..text = 'Connect to a different VM',
+      new SpanElement()..text = ']',
+      new ButtonElement()..innerHtml = '&times;'
+        ..onClick.map(_toEvent).listen(_remove)
+    ]);
+    children = [
+      new DivElement()
+        ..children = content
+    ];
+  }
+
+  ExceptionRemoveEvent _toEvent(_) {
+    return new ExceptionRemoveEvent(exception, stacktrace: stacktrace);
+  }
+
+  void _remove(ExceptionRemoveEvent e) {
+    if (_onRemove.hasListener) {
+      _onRemove.add(e);
+    }
+  }
+}