Centralized event streams

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

 // Copyright (c) 2013, 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.
 
 library flag_list_element;
 
 import 'dart:html';
 import 'dart:async';
 import 'package:observatory/models.dart' as M;
 import 'package:observatory/src/elements/helpers/rendering_scheduler.dart';
@@ skipping 15 matching lines @@
                                           NavRefreshElement.tag,
                                           NavTopMenuElement.tag,
                                           NavVMMenuElement.tag,
                                           ViewFooterElement.tag,]);
 
   RenderingScheduler _r;
 
   Stream<RenderedEvent<FlagListElement>> get onRendered => _r.onRendered;
 
   M.VMRef _vm;
-  Stream<M.VMUpdateEvent> _vmUpdates;
+  M.EventRepository _events;
   M.FlagsRepository _repository;
   M.NotificationRepository _notifications;
   Iterable<M.Flag> _flags;
 
   M.VMRef get vm => _vm;
 
   factory FlagListElement(M.VMRef vm,
-                          Stream<M.VMUpdateEvent> vmUpdates,
+                          M.EventRepository events,
                           M.FlagsRepository repository,
                           M.NotificationRepository notifications,
                           {RenderingQueue queue}) {
     assert(vm != null);
-    assert(vmUpdates != null);
+    assert(events != null);
     assert(repository != null);
     assert(notifications != null);
     FlagListElement e = document.createElement(tag.name);
     e._r = new RenderingScheduler(e, queue: queue);
     e._vm = vm;
-    e._vmUpdates = vmUpdates;
+    e._events = events;
     e._repository = repository;
     e._notifications = notifications;
     return e;
   }
 
   FlagListElement.created() : super.created();
 
   @override
   void attached() {
     super.attached();
+    _refresh();
     _r.enable();
-    _refresh();
   }
 
   @override
   void detached() {
     super.detached();
     children = [];
     _r.disable(notify: true);
   }
 
   void render() {
@@ skipping 18 matching lines @@
         content.add(new HeadingElement.h2()..text = 'None');
       } else {
         content.addAll(unmodified.expand(_renderFlag));
       }
     }
 
     children = [
       new NavBarElement(queue: _r.queue)
         ..children = [
           new NavTopMenuElement(queue: _r.queue),
-          new NavVMMenuElement(_vm, _vmUpdates, queue: _r.queue),
+          new NavVMMenuElement(_vm, _events, queue: _r.queue),
           new NavMenuElement('flags', link: Uris.flags(), last: true,
                              queue: _r.queue),
           new NavRefreshElement(queue: _r.queue)
             ..onRefresh.listen((e) async {
               e.element.disabled = true;
               try {
                 await _refresh();
               } finally {
                 e.element.disabled = false;
               }
             }),
           new NavNotifyElement(_notifications, queue: _r.queue)
         ],
       new DivElement()
         ..classes = ['content-centered']
         ..children = content,
       new ViewFooterElement(queue: _r.queue)
     ];
   }
 
-  Future _refresh() async {
-    _flags = await _repository.list(_vm);
-    _r.dirty();
+  Future _refresh() {
+    return _repository.list().then((flags) {
+      _flags = flags;
+      _r.dirty();
+    });
   }
 
   static bool _isModified(M.Flag flag) => flag.modified;
   static bool _isUnmodified(M.Flag flag) => !flag.modified;
 
   static List<Element> _renderFlag(M.Flag flag) {
     return [
       new SpanElement()..classes = const ['comment']
         ..text = '// ${flag.comment}',
       new DivElement()..classes = flag.modified ? const ['flag', 'modified']
                                                 : const ['flag', 'unmodified']
         ..children = [
           new SpanElement()..classes = const ['name']
             ..text = flag.name,
           new SpanElement()..text = '=',
           new SpanElement()..classes = const ['value']
             ..text = flag.valueAsString ?? 'NULL'
         ],
       new BRElement(),
     ];
   }
 }