Simple Tree View implementation for IMGUI (Editor GUI) in Unity. Includes a special type for working with asset paths, but base data structure and view can be easily extended to support anything.
Built and tested in Unity 5.6.0
The Tree View is made up of two parts, a tree data structure TreeNode and an IMGUI control TreeIMGUI. The project comes with a basic tree data structure which can be easily extended or wrapped in a container class (demonstrated with AssetTree).
The IMGUI control produces a basic tree layout with foldout support, it can be easily extended to customise the appearance of rows by overriding OnDrawTreeNode and for more advanced layouts OnDrawRow and OnGetLayoutHeight.
For the standard IMGUI control to work data contained within a TreeNode must implement the ITreeIMGUIData interface.
The project contains an example implementation AssetTreeWindow which demonstrates how a tree view can be used to list asset search results. The example can be loaded via the Unity editor window under Tools/Tree View Example Window.