menu

README

menu

Menu provides methods to construct flexible menu trees that are independent from the representation.

Documentation

Index

• type Json
• type Leaf
  • func Item(text, path string) Leaf
• type Node
  • func (n *Node) FindByPath(path string) *Node
  • func (n *Node) FindByText(text string) *Node
  • func (n Node) MarshalJSON() ([]byte, error)
  • func (n *Node) RootAt(depth int, path string) *Node
  • func (n *Node) UnmarshalJSON(data []byte) (err error)
• type WriterTo
• type WriterToFunc
  • func (wf WriterToFunc) WriterTo(root *Node, depth int, path string) io.WriterTo

Types

type Json

type Json struct {
	Text string `json:",omitempty"`
	Path string `json:",omitempty"`
	Subs []Json `json:",omitempty"`
}

helper for simple json based loading and saving

type Leaf

type Leaf interface {

	// Path returns the URL path for the leaf.
	// If it returns an empty string or a string that begins with ~ or $, the leaf
	// is not treated as a link.
	Path() string

	// String returns the string that is used to represent the leaf.
	// If the leaf is treated as a link (see Path()), String() would return the
	// linked text.
	String() string
}

Leaf is the content of a Node It can be used for the html representation of the menu

func Item

func Item(text, path string) Leaf

Item creates a menu item, based on the given text and path. The returned item can be used as leaf in a menu tree.

type Node

type Node struct {
	// Edges is a collection of menu nodes that are children the current node
	Edges []*Node

	// Leaf contains the item of the current node.
	// The root node of a menu tree has no leaf (<nil>).
	Leaf Leaf
}

Node is a node of a menu tree

func (*Node) FindByPath

func (n *Node) FindByPath(path string) *Node

FindByPath returns the first node that has the given path by starting with the leaf of m and then going through its egdes. If no node is found, <nil> is returned

func (*Node) FindByText

func (n *Node) FindByText(text string) *Node

FindByText returns the first node that has the given text by starting with the leaf and then going through its egdes. If no node is found, <nil> is returned

func (Node) MarshalJSON

func (n Node) MarshalJSON() ([]byte, error)

func (*Node) RootAt

func (n *Node) RootAt(depth int, path string) *Node

RootAt looks for the node with the given path and returns its parent node at nesting level depth. It can be used to get a sub menu for the request path within a http handler to show it in the layout at a different place than other parts of the menu tree. The returned node is a copy of the original node (without the leaf) and may not be used to manipulate the original node. For the later, FindByText() or FindByPath() can be used. If a node was found but it has no edges, <nil> is returned.

func (*Node) UnmarshalJSON

func (n *Node) UnmarshalJSON(data []byte) (err error)

UnmarshalJSON([]byte) error

type WriterTo

type WriterTo interface {

	// WriterTo returns an io.WriterTo that writes the menu tree for the given root node.
	// The leaf matching the given path may be treated in a special way.
	// The given path may be seen as "active" or "selected" path.
	// The tree should only be visited up to the given depth.
	// WriterTo must handle the case when the root is <nil> (empty menu).
	WriterTo(root *Node, depth int, path string) io.WriterTo
}

WriterTo provides a WriterTo that writes a representation of a menu tree

type WriterToFunc

type WriterToFunc func(root *Node, depth int, path string) io.WriterTo

func (WriterToFunc) WriterTo

func (wf WriterToFunc) WriterTo(root *Node, depth int, path string) io.WriterTo