Deletion/ownership

mojo/services/public/cpp/view_manager/lib/view_tree_node.cc

 // Copyright 2014 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 "mojo/services/public/cpp/view_manager/view_tree_node.h"
 
 #include "mojo/services/public/cpp/view_manager/lib/view_manager_private.h"
 #include "mojo/services/public/cpp/view_manager/lib/view_manager_synchronizer.h"
 #include "mojo/services/public/cpp/view_manager/lib/view_tree_node_private.h"
 #include "mojo/services/public/cpp/view_manager/view_tree_node_observer.h"
@@ skipping 72 matching lines @@
       std::find(children->begin(), children->end(), child);
   if (it != children->end()) {
     children->erase(it);
     ViewTreeNodePrivate(child).ClearParent();
   }
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // ViewTreeNode, public:
 
-ViewTreeNode::ViewTreeNode()
-    : manager_(NULL),
-      id_(-1),
-      owned_by_parent_(true),
-      parent_(NULL) {}
+// static
+ViewTreeNode* ViewTreeNode::Create(ViewManager* view_manager) {
+  ViewTreeNode* node = new ViewTreeNode(view_manager);
+  ViewManagerPrivate(view_manager).AddNode(node->id(), node);
+  return node;
+}
 
-ViewTreeNode::ViewTreeNode(ViewManager* manager)
-    : manager_(manager),
-      id_(ViewManagerPrivate(manager).synchronizer()->CreateViewTreeNode()),
-      owned_by_parent_(true),
-      parent_(NULL) {}
-
-ViewTreeNode::~ViewTreeNode() {
-  while (!children_.empty()) {
-    ViewTreeNode* child = children_.front();
-    if (child->owned_by_parent_) {
-      delete child;
-      // Deleting the child also removes it from our child list.
-      DCHECK(std::find(children_.begin(), children_.end(), child) ==
-             children_.end());
-    } else {
-      RemoveChild(child);
-    }
-  }
-
-  if (parent_)
-    parent_->RemoveChild(this);
-
+void ViewTreeNode::Destroy() {
   if (manager_)
     ViewManagerPrivate(manager_).synchronizer()->DestroyViewTreeNode(id_);
+  while (!children_.empty())
+    children_.front()->Destroy();
+  LocalDestroy();
 }
 
 void ViewTreeNode::AddObserver(ViewTreeNodeObserver* observer) {
   observers_.AddObserver(observer);
 }
 
 void ViewTreeNode::RemoveObserver(ViewTreeNodeObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
@@ skipping 24 matching lines @@
   Children::const_iterator it = children_.begin();
   for (; it != children_.end(); ++it) {
     ViewTreeNode* node = (*it)->GetChildById(id);
     if (node)
       return node;
   }
   return NULL;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+// ViewTreeNode, protected:
+
+ViewTreeNode::ViewTreeNode()
+    : manager_(NULL),
+      id_(-1),
+      parent_(NULL) {}
+
+ViewTreeNode::~ViewTreeNode() {
+  FOR_EACH_OBSERVER(
+      ViewTreeNodeObserver,
+      observers_,
+      OnNodeDestroy(this, ViewTreeNodeObserver::DISPOSITION_CHANGING));
+  if (parent_)
+    parent_->LocalRemoveChild(this);
+  FOR_EACH_OBSERVER(
+      ViewTreeNodeObserver,
+      observers_,
+      OnNodeDestroy(this, ViewTreeNodeObserver::DISPOSITION_CHANGED));
+  if (manager_)
+    ViewManagerPrivate(manager_).RemoveNode(id_);
+}
+
+////////////////////////////////////////////////////////////////////////////////
 // ViewTreeNode, private:
 
+ViewTreeNode::ViewTreeNode(ViewManager* manager)
+    : manager_(manager),
+      id_(ViewManagerPrivate(manager).synchronizer()->CreateViewTreeNode()),
+      parent_(NULL) {}
+
+void ViewTreeNode::LocalDestroy() {
+  delete this;
+}
+
 void ViewTreeNode::LocalAddChild(ViewTreeNode* child) {
   ScopedTreeNotifier notifier(child, child->parent(), this);
   if (child->parent())
     RemoveChildImpl(child, &child->parent_->children_);
   children_.push_back(child);
   child->parent_ = this;
 }
 
 void ViewTreeNode::LocalRemoveChild(ViewTreeNode* child) {
   DCHECK_EQ(this, child->parent());
   ScopedTreeNotifier(child, this, NULL);
   RemoveChildImpl(child, &children_);
 }
 
 }  // namespace view_manager
 }  // namespace services
 }  // namespace mojo