Arborist.Config

Configuration and view context for the tree editor.

Config

type alias Config item =

{ view : Context item -> Maybe item -> Html (Msg item)

, layout : Layout

}

Global configuration for the editor module, consisting of two fields:

view: the view of a single node function, dependent on its Context and the item it holds (may be Nothing in case of a placeholder). Since there are all sorts of event handlers on the node element containing this piece of html, the library essentially disallows any messages (it does so by expecting the message type to be of Msg item, but does not actually expose any Msg constructors)
layout: bits of geometry information, detailed here

type alias Layout =

{ canvasWidth : Float

, canvasHeight : Float

, nodeWidth : Float

, nodeHeight : Float

, level : Float

, gutter : Float

}

Layout dimensions for the tree editor, with the following fields:

canvasWidth: width of the canvas containing the entire editor interface
canvasHeight: height of the canvas containing the entire editor interface
nodeWidth: width of a single node
nodeHeight: height of a single node
level: vertical offset between different levels of nodes (from the bottom of the parent to the top of the child)
gutter: horizontal gutter between two sibling nodes

= Normal

| Active

| Hovered

| DropTarget

The state of a node at a given time. May be normal one of the following:

Normal: node in rest state
Hovered: a hovered over node
Active: an activated node. Overrides hover
DropTarget: indicates that a swap or insert of the dragged subtree will take place at this node upon release

type alias Context item =

{ parent : Maybe item

, siblings : List item

, children : List item

, state : NodeState

}

View context. Contains the following fields: