tree: Inserts a tree widget

The tree tag displays a dynamic tree widget by querying Zope objects.

Syntax

tree tag syntax:

      <dtml-tree [VariableName|expr="VariableExpression"]>
      </dtml-tree>

The tree tag is a block tag. It renders a dynamic tree widget in HTML. The root of the tree is given by variable name or expression, if present, otherwise it defaults to the current object. The tree block is rendered for each tree node, with the current node pushed onto the DTML namespace.

Tree state is set in HTTP cookies. Thus for trees to work, cookies must be enabled. Also you can only have one tree per page.

Attributes

branches=string

Finds tree branches by calling the named method. The default method is tpValues which most Zope objects support.

branches_expr=string

Finds tree branches by evaluating the expression.

id=string

The name of a method or id to determine tree state. It defaults to tpId which most Zope objects support. This attribute is for advanced usage only.

url=string

The name of a method or attribute to determine tree item URLs. It defaults to tpURL which most Zope objects support. This attribute is for advanced usage only.

leaves=string

The name of a DTML Document or Method used to render nodes that don't have any children. Note: this document should begin with <dtml-var standard_html_header> and end with <dtml-var standard_html_footer> in order to ensure proper display in the tree.

header=string

The name of a DTML Document or Method displayed before expanded nodes. If the header is not found, it is skipped.

footer=string

The name of a DTML Document or Method displayed after expanded nodes. If the footer is not found, it is skipped.

nowrap=boolean

If true then rather than wrap, nodes may be truncated to fit available space.

sort=string

Sorts the branches by the named attribute.

reverse

Reverses the order of the branches.

assume_children=boolean

Assumes that nodes have children. This is useful if fetching and querying child nodes is a costly process. This results in plus boxes being drawn next to all nodes.

single=boolean

Allows only one branch to be expanded at a time. When you expand a new branch, any other expanded branches close.

skip_unauthorized

Skips nodes that the user is unauthorized to see, rather than raising an error.

urlparam=string

A query string which is included in the expanding and contracting widget links. This attribute is for advanced usage only.

prefix=string

Provide versions of the tag variables that start with this prefix instead of "tree", and that use underscores () instead of hyphens (-). The prefix must start with a letter and contain only alphanumeric characters and underscores ().

Tag Variables

tree-item-expanded

True if the current node is expanded.

tree-item-url

The URL of the current node.

tree-root-url

The URL of the root node.

tree-level

The depth of the current node. Top-level nodes have a depth of zero.

tree-colspan

The number of levels deep the tree is being rendered. This variable along with the tree-level variable can be used to calculate table rows and colspan settings when inserting table rows into the tree table.

tree-state

The tree state expressed as a list of ids and sub-lists of ids. This variable is for advanced usage only.

Tag Control Variables

You can control the tree tag by setting these variables.

expand_all

If this variable is true then the entire tree is expanded.

collapse_all

If this variable is true then the entire tree is collapsed.

Examples

Display a tree rooted in the current object:

      <dtml-tree>
        <dtml-var title_or_id>
      </dtml-tree>

Display a tree rooted in another object, using a custom branches method:

      <dtml-tree expr="folder.object" branches="objectValues">
        Node id : <dtml-var getId>
      </dtml-tree>