Converted Observatory object-common element

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

Index: runtime/observatory/lib/src/elements/retaining_path.dart
diff --git a/runtime/observatory/lib/src/elements/retaining_path.dart b/runtime/observatory/lib/src/elements/retaining_path.dart
new file mode 100644
index 0000000000000000000000000000000000000000..40f77e8cc5878ba027f7bfa8f43145dc2c81f789
--- /dev/null
+++ b/runtime/observatory/lib/src/elements/retaining_path.dart
@@ -0,0 +1,127 @@
+// 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/models.dart' as M;
+import 'package:observatory/src/elements/curly_block.dart';
+import 'package:observatory/src/elements/instance_ref.dart';
+import 'package:observatory/src/elements/helpers/any_ref.dart';
+import 'package:observatory/src/elements/helpers/rendering_scheduler.dart';
+import 'package:observatory/src/elements/helpers/tag.dart';
+
+class RetainingPathElement extends HtmlElement implements Renderable {
+  static const tag = const Tag<RetainingPathElement>('retaining-path',
+    dependencies: const [
+        CurlyBlockElement.tag,
+        InstanceRefElement.tag
+    ]);
+
+  RenderingScheduler<RetainingPathElement> _r;
+
+  Stream<RenderedEvent<RetainingPathElement>> get onRendered =>
+    _r.onRendered;
+
+  M.IsolateRef _isolate;
+  M.ObjectRef _object;
+  M.RetainingPathRepository _retainingPaths;
+  M.InstanceRepository _instances;
+  M.RetainingPath _path;
+  bool _expanded = false;
+
+  M.IsolateRef get isolate => _isolate;
+  M.ObjectRef get object => _object;
+
+  factory RetainingPathElement(M.IsolateRef isolate, M.ObjectRef object,
+      M.RetainingPathRepository retainingPaths, M.InstanceRepository instances,
+      {RenderingQueue queue}) {
+    assert(isolate != null);
+    assert(object != null);
+    assert(retainingPaths != null);
+    assert(instances != null);
+    RetainingPathElement e = document.createElement(tag.name);
+    e._r = new RenderingScheduler(e, queue: queue);
+    e._isolate = isolate;
+    e._object = object;
+    e._retainingPaths = retainingPaths;
+    e._instances = instances;
+    return e;
+  }
+
+  RetainingPathElement.created() : super.created();
+
+  @override
+  void attached() {
+    super.attached();
+    _r.enable();
+  }
+
+  @override
+  void detached() {
+    super.detached();
+    children = [];
+    _r.disable(notify: true);
+  }
+
+  void render() {
+    children = [
+      new CurlyBlockElement(expanded: _expanded, queue: _r.queue)
+        ..children = _createContent()
+        ..onToggle.listen((e) async {
+          _expanded = e.control.expanded;
+          if (_expanded) {
+            e.control.disabled = true;
+            await _refresh();
+            e.control.disabled = false;
+          }
+        })
+    ];
+  }
+
+  Future _refresh() async {
+    _path = null;
+    _path = await _retainingPaths.get(_isolate, _object.id);
+    _r.dirty();
+  }
+
+  List<Element> _createContent() {
+    if (_path == null) {
+      return [
+        new SpanElement()..text = 'Loading'
+      ];
+    }
+    return _path.elements.map(_createItem).toList();
+  }
+
+  Element _createItem(M.RetainingPathItem item) {
+    final content = <Element>[];
+
+    if (item.parentField != null) {
+      content.add(
+        new DivElement()
+          ..children = [
+              new SpanElement()..text = 'from ',
+                new InstanceRefElement(_isolate, item.parentField, _instances,
+                                       queue: _r.queue),
+              new SpanElement()..text = ' of ',
+          ]);
+    } else if (item.parentListIndex != null) {
+      content.add(
+        new SpanElement()
+          ..text = 'from [ ${item.parentListIndex} ] of ');
+    } else if (item.parentWordOffset != null) {
+      content.add(
+        new SpanElement()
+          ..text = 'from word [ ${item.parentWordOffset} ] of ');
+    } else {
+      content.add(new SpanElement()..text = 'from ');
+    }
+
+    content.add(
+      anyRef(_isolate, item.source, _instances, queue: _r.queue)
+    );
+
+    return new DivElement()..classes = ['indent']..children = content;
+  }
+}