1 files changed, 53 insertions, 0 deletions
diff --git a/source/blender/editors/space_outliner/tree/tree_element.hh b/source/blender/editors/space_outliner/tree/tree_element.hh
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+++ b/source/blender/editors/space_outliner/tree/tree_element.hh
@@ -0,0 +1,53 @@
+/*
+ * This program 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 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+/** \file
+ * \ingroup spoutliner
+ */
+
+#pragma once
+
+#include "tree_element.h"
+
+namespace blender::ed::outliner {
+
+/* -------------------------------------------------------------------- */
+/* Tree-Display Interface */
+
+class AbstractTreeElement {
+ protected:
+  /**
+   * Reference back to the owning legacy TreeElement.
+   * Most concrete types need access to this, so storing here. Eventually the type should be
+   * replaced by AbstractTreeElement and derived types.
+   */
+  TreeElement &legacy_te_;
+
+ public:
+  AbstractTreeElement(TreeElement &legacy_te) : legacy_te_(legacy_te)
+  {
+  }
+  virtual ~AbstractTreeElement() = default;
+
+  /**
+   * Let the type add its own children.
+   */
+  virtual void expand(SpaceOutliner &) const
+  {
+  }
+};
+
+}  // namespace blender::ed::outliner