1.175.2 Send methods

tree ->collapsed_handler: recogniser

Attach a recogniser for all nodes that have node<->collapsed. See tree->event for the interpretation.

See also

- node-collapsed
- tree->event

tree ->compute:

Whenever something changes to the tree that might affect its layout, this is notified using graphical->request_compute. tree->compute recomputes the layout of the tree by invoking tree->layout.

tree ->direction: {horizontal,vertical,list}

@see tree-parent_handle

tree ->event: event

tree->event allows for centralised event-processing for all nodes displayed on the tree. It performs the following steps.

1. Invoke device->event. When successful, succeed.
2. Invoke node->event on the node below the pointer.

• * Finding the Context Arguments The most reliable way to find the various context objects are:

  @event?receiver	Graphical receiving the event
  @event?receiver?node	Node object for this graphical
  @event?receiver?device	The tree object

  See also

  - tree->root_handler
  - tree->node_handler
  - tree->leaf_handler
  - tree->collapsed_handler
  - graphical<-node
  - tree-root_handlers
  - tree-node_handlers
  - tree-leaf_handlers
  - tree-collapsed_handlers

tree ->for_some: code

Run code on all nodes.

tree ->for_all: code

Invokes the message to the tree<-root of the tree, iterating over all nodes of the tree. See also node->for_all, node->for_some and tree<-contains.

See also

- node->for_all
- tree->for_some

tree ->initialise: root=[node]*

Create a tree object and assign it a root. When the root is @nil (default), the tree must be assigned a root using tree->root before any other nodes may be attached.

Note that class node defines a convert method for graphicals that creates a node with the specified graphical as node<-image.

See also

tree->root

tree ->layout:

Recompute the layout of the tree. This method is normally called from tree->compute and sends the following three messages to tree<-display_root:

node->compute_level	Update the node<-level slots
node->compute_size	Compute the sizes of all nodes
node->compute_layout	Place the nodes

tree ->leaf_handler: recogniser

Attach a recogniser for all nodes that have no sons (i.e. are leaves). See tree->event for the interpretation.

See also

tree->event

tree ->level_gap: int

@see tree-neighbour_gap

tree ->neighbour_gap: int

@see tree-neighbour_gap

tree ->node_handler: recogniser

Attach a recogniser for all nodes. See tree->event for the interpretation.

See also

tree->event

tree ->root: root=node*, relink=[bool]

@see !already_has_root @see tree->initialise

tree ->root_handler: recogniser

Attach a recogniser for the tree<-display_root node. See‘tree tree->event’for the interpretation.

See also

tree->event

tree ->unzoom:

Equivalent to:

send(Tree, zoom, Tree?root).

To unzoom only one level, use

send(Tree, zoom, Tree?display_root?parents?head).

Note that this method is ambiguous when the display_root has multiple parents.

See also

- node->unzoom
- tree->zoom

tree ->zoom: node

Zoom in for a particular subtree. The visualisation of the tree will behave as if the argument-node of this method is the root. Sets the variable tree<-display_root.

See also

- node->zoom
- node-displayed
- node-collapsed
- tree->unzoom
- tree-display_root