Add key viewer
diff --git a/src/key-tree-item.cpp b/src/key-tree-item.cpp
new file mode 100644
index 0000000..070537e
--- /dev/null
+++ b/src/key-tree-item.cpp
@@ -0,0 +1,104 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2014, Regents of the University of California,
+ *
+ * This file is part of NFD Control Center.  See AUTHORS.md for complete list of NFD
+ * authors and contributors.
+ *
+ * NFD Control Center is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NFD Control Center is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with NFD
+ * Control Center, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include <QStringList>
+#include "key-tree-item.hpp"
+
+namespace ndn {
+namespace ncc {
+
+KeyTreeItem::KeyTreeItem(const QVariant& name, const QVariant& data, Type type, KeyTreeItem* parent)
+  : m_name(name)
+  , m_data(data)
+  , m_type(type)
+  , m_parentItem(parent)
+{
+}
+
+KeyTreeItem::~KeyTreeItem()
+{
+  qDeleteAll(m_childItems);
+}
+
+void
+KeyTreeItem::setParent(KeyTreeItem* parent)
+{
+  m_parentItem = parent;
+}
+
+void
+KeyTreeItem::appendChild(KeyTreeItem* item)
+{
+  m_childItems.append(item);
+}
+
+KeyTreeItem*
+KeyTreeItem::child(int row)
+{
+  return m_childItems.value(row);
+}
+
+int
+KeyTreeItem::childCount() const
+{
+  return m_childItems.count();
+}
+
+int
+KeyTreeItem::columnCount() const
+{
+  return 1;
+}
+
+QVariant
+KeyTreeItem::name() const
+{
+  return m_name;
+}
+
+QVariant
+KeyTreeItem::data() const
+{
+  return m_data;
+}
+
+KeyTreeItem::Type
+KeyTreeItem::type() const
+{
+  return m_type;
+}
+
+KeyTreeItem*
+KeyTreeItem::parentItem()
+{
+  return m_parentItem;
+}
+
+int
+KeyTreeItem::row() const
+{
+  if (m_parentItem)
+    return m_parentItem->m_childItems.indexOf(const_cast<KeyTreeItem*>(this));
+
+  return 0;
+}
+
+} // namespace ndn
+} // namespace ncc