Experimental alignment layout manager using a property on the views

ui/views/attributes.cc

+// Copyright (c) 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ui/views/attributes.h"
+
+namespace views {
+
+AttributeId Attribute::Identity() const {
+  return GetAttributeId<Attribute>();
+}
+
+AttributeContainer::AttributeContainer(View* view) : view_(view) {}
+
+AttributeContainer::AttributeContainer() : view_(nullptr) {}
+
+AttributeContainer::~AttributeContainer() {}
+
+bool AttributeContainer::Remove(const AttributeId attributeId) {
+  AttributeMap::const_iterator it = map_.find(attributeId);
+  bool canRemove = it != map_.cend();
+  if (canRemove) {
+    Notification(Attribute::NotifyType::AttributeRemoved, it->second.get());
+    it->second.get()->RemovedFromView();
+    map_.erase(it);
+  }
+  return canRemove;
+}
+
+void AttributeContainer::Notification(Attribute::NotifyType type,
+                                      Attribute* attribute) {
+  for (AttributeMap::const_iterator a = map_.cbegin(); a != map_.cend(); a++) {
+    Attribute* attr = a->second.get();
+    if (attr != attribute)
+      attr->Notification(type, attribute);
+  }
+}
+
+void AttributeContainer::ViewNotification(View* view) {
+  for (AttributeMap::const_iterator a = map_.cbegin(); a != map_.cend(); a++)
+    a->second.get()->ViewNotification(view);
+}
+
+AttributeIdFactory::AttributeIdMap AttributeIdFactory::map_;
+
+AttributeId AttributeIdFactory::GetAttributeId(const char* typeName) {
+  std::string type_name = typeName;
+  AttributeIdMap::const_iterator it = map_.find(type_name);
+  if (it == map_.cend()) {
+    std::unique_ptr<AttributeIdHolder> holder =
+        base::WrapUnique(new AttributeIdHolder());
+    it = map_.insert(AttributeIdMap::value_type(type_name, std::move(holder)))
+             .first;
+  }
+  return it->second.get()->GetAttributeId();
+}
+
+}  // namespace views