Tree Nodes

A SharedTree's data is organized into a tree of nodes. See node types for details on the available node types.

Node Utilities

The Tree singleton provides utilities for inspecting and navigating nodes — methods that can't live on TreeNode directly due to the risk of name collisions with object-node fields. The following covers commonly used ones; see the API documentation for the full list.

• Tree.parent — Returns the parent node. Useful when you need to act on a node's container rather than the node itself — for example, to remove it:

  const parent = Tree.parent(note);
  
  if (Tree.is(parent, Notes) || Tree.is(parent, Items)) {
  	const index = parent.indexOf(note);
  	parent.removeAt(index);
  }

• Tree.contains — Returns whether a node is a descendant of another — for example, to confirm a node belongs to a particular section, or to guard against creating a cycle when moving a node.

• Tree.status — Returns the TreeStatus of a node. Many editing operations require a specific status.

  • New — created but not yet inserted into the tree
  • InDocument — parented under the root field
  • Removed — not under the root field, but can be added back
  • Deleted — removed and cannot be added back

• Tree.schema — Returns the TreeNodeSchema for a node; useful when the node's type isn't statically known.

• Tree.shortId — Returns the identifier for a node defined with a SchemaFactory.identifier field — useful for cross-referencing nodes by stable ID rather than position.

• Tree.on — Subscribes to change events on a node. See Events for details.

• Tree.is — Narrows a node's type to a specific SchemaFactory-derived class. Use when the node's type is unknown:

  if (Tree.is(myNode, Note)) {
  	// myNode is typed as Note here
  }