This is a small utility that provides quite configurable tree view list. It is based on standard android list view. It separates out different aspects of the tree: there is a separate list view, tree adapter, tree state manager and tree state builder.

Tree view provides the frame to display the view.
Adapter allows to create visual representation of each tree node.
State manager provides storage for tree state (connections between parents and children, collapsed/expanded state). It provides all the low-level tree manipulation methods.
Tree builder allows to build tree easily providing higher level methods. The tree can be build either from prepared sequentially prepared list of nodes (node id, level) or using (parent/child relationships).

For now only in-memory state manager is provided, but Tree State Manger interface is done in the way that database tree manager even for large trees is potentially supported.