Introduce a QML tree model

Goal

Introduce a QML type to create and store tree-like data structures (e.g. JavaScript/JSON objects) for a tree model to be used with TreeView. It is intended to support simple models with pure QML; without requiring the creation of a custom QAbstractItemModel subclass in C++.

Description

The model can be stored as a simple collection of nodes with hierarchical relationship between them. A node can have multiple children but only one parent (with the exception of the root node)

The basic functionalities are expected from QML:

Node management:

• Dynamically add or remove nodes
• Enable node set/update (directly in the model or by using custom delegates)
• Be able to move a node in the structure

Tree traversal

• Easily traverse the tree model
• Iterate the model

Relationship:

• Parent and child access on the node level

Event handling:

• Be able to update the tree on changes in the model

Data validation:

• Consider invalid models, for instance, a child having multiple parents

Tree data:

• Be able to query the number of edges and the depth of a node

Notes

• Consider performance implication for large data sets.
• Consider future improvements where user could add data from XML tree models or JSON files.
• Consider future improvements to search the model
• Consider the possibility to switch the same model as tree or table view.