Centralized event streams

runtime/observatory/lib/src/elements/vm_connect.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.
 
 library vm_connect_element;
 
 import 'dart:html';
 import 'dart:async';
 import 'dart:convert';
 import 'package:observatory/models.dart' as M;
 import 'package:observatory/src/elements/helpers/tag.dart';
 import 'package:observatory/src/elements/helpers/rendering_scheduler.dart';
 import 'package:observatory/src/elements/nav/bar.dart';
 import 'package:observatory/src/elements/nav/notify.dart';
 import 'package:observatory/src/elements/nav/top_menu.dart';
 import 'package:observatory/src/elements/view_footer.dart';
 import 'package:observatory/src/elements/vm_connect_target.dart';
 
+typedef void CrashDumpLoadCallback(Map dump);
+
 class VMConnectElement extends HtmlElement implements Renderable {
   static const tag = const Tag<VMConnectElement>('vm-connect',
                      dependencies: const [NavBarElement.tag,
                                           NavTopMenuElement.tag,
                                           NavNotifyElement.tag,
                                           ViewFooterElement.tag,
                                           VMConnectTargetElement.tag]);
 
   RenderingScheduler _r;
 
   Stream<RenderedEvent<VMConnectElement>> get onRendered => _r.onRendered;
 
-  M.CrashDumpRepository _dump;
+  CrashDumpLoadCallback _loadDump;
   M.NotificationRepository _notifications;
   M.TargetRepository _targets;
   StreamSubscription _targetsSubscription;
 
   String _address;
 
   factory VMConnectElement(M.TargetRepository targets,
-                           M.CrashDumpRepository dump,
+                           CrashDumpLoadCallback loadDump,
                            M.NotificationRepository notifications,
                            {String address: '', RenderingQueue queue}) {
     assert(address != null);
-    assert(dump != null);
+    assert(loadDump != null);
     assert(notifications != null);
     assert(targets != null);
     VMConnectElement e = document.createElement(tag.name);
     e._r = new RenderingScheduler(e, queue: queue);
     e._address = address;
-    e._dump = dump;
+    e._loadDump = loadDump;
     e._notifications = notifications;
     e._targets = targets;
     return e;
   }
 
   VMConnectElement.created() : super.created();
 
   @override
   void attached() {
-    super.attached(); _r.enable();
+    super.attached();
     _targetsSubscription = _targets.onChange.listen((_) => _r.dirty());
+    _r.enable();
   }
 
   @override
   void detached() {
-    super.detached(); children = []; _r.disable(notify: true);
-    _targetsSubscription.cancel(); _targetsSubscription = null;
+    super.detached();
+    children = [];
+    _r.disable(notify: true);
+    _targetsSubscription.cancel();
   }
 
   void render() {
     final host = window.location.hostname;
     final port = window.location.port;
     children = [
       new NavBarElement(queue: _r.queue)
         ..children = [
           new NavTopMenuElement(last: true, queue: _r.queue),
           new NavNotifyElement(_notifications, queue: _r.queue)
@@ skipping 74 matching lines @@
   }
 
   FileUploadInputElement _createCrushDumpLoader() {
     FileUploadInputElement e = new FileUploadInputElement()
       ..id = 'crashDumpFile';
     e.onChange.listen((_) {
       var reader = new FileReader();
       reader.readAsText(e.files[0]);
       reader.onLoad.listen((_) {
         var crashDump = JSON.decode(reader.result);
-        _dump.load(crashDump);
+        _loadDump(crashDump);
       });
     });
     return e;
   }
   void _create() {
     if (_address == null || _address.isEmpty) return;
     _targets.add(_normalizeStandaloneAddress(_address));
   }
   void _connect(TargetEvent e) => _targets.setCurrent(e.target);
   void _delete(TargetEvent e) => _targets.delete(e.target);
 
   static String _normalizeStandaloneAddress(String networkAddress) {
     if (networkAddress.startsWith('ws://')) {
       return networkAddress;
     }
     return 'ws://${networkAddress}/ws';
   }
 }