React Simple Tree Menu

Inspired by Downshift, a simple, data-driven, light-weight React Tree Menu component that:

• does not depend on any UI framework
• fully customizable with render props and control props
• allows search
• supports keyboard browsing

Check Storybook Demo.

Usage

Install with the following command in your React app:

npm i react-simple-tree-menu
// or
yarn add react-simple-tree-menu

To generate a TreeMenu, you need to provide data in the following structure.

// as an array
const treeData = [
  {
    key: 'first-level-node-1',
    label: 'Node 1 at the first level',
    ..., // any other props you need, e.g. url
    nodes: [
      {
        key: 'second-level-node-1',
        label: 'Node 1 at the second level',
        nodes: [
          {
            key: 'third-level-node-1',
            label: 'Last node of the branch',
            nodes: [] // you can remove the nodes property or leave it as an empty array
          },
        ],
      },
    ],
  },
  {
    key: 'first-level-node-2',
    label: 'Node 2 at the first level',
  },
];
// or as an object
const treeData = {
  'first-level-node-1': {               // key
    label: 'Node 1 at the first level',
    index: 0, // decide the rendering order on the same level
    ...,      // any other props you need, e.g. url
    nodes: {
      'second-level-node-1': {
        label: 'Node 1 at the second level',
        index: 0,
        nodes: {
          'third-level-node-1': {
            label: 'Node 1 at the third level',
            index: 0,
            nodes: {} // you can remove the nodes property or leave it as an empty array
          },
        },
      },
    },
  },
  'first-level-node-2': {
    label: 'Node 2 at the first level',
    index: 1,
  },
};

And then import TreeMenu and use it. By default you only need to provide data. You can have more control over the behaviors of the components using the provided API.

import TreeMenu from 'react-simple-tree-menu';
...
// import default minimal styling or your own styling
import '../node_modules/react-simple-tree-menu/dist/main.css';
// Use the default minimal UI
<TreeMenu data={treeData} />

// Use any third-party UI framework
<TreeMenu
  data={treeData}
  onClickItem={({ key, label, ...props }) => {
    this.navigate(props.url); // user defined prop
  }}
  initialActiveKey='first-level-node-1/second-level-node-1' // the path to the active node
  debounceTime={125}>
    {({ search, items }) => (
        <>
          <Input onChange={e => search(e.target.value)} placeholder="Type and search" />
          <ListGroup>
            {items.map(props => (
              // You might need to wrap the third-party component to consume the props
              // check the story as an example
              // https://github.com/iannbing/react-simple-tree-menu/blob/master/stories/index.stories.js
              <ListItem {...props} />
            ))}
          </ListGroup>
        </>
    )}
</TreeMenu>

If you want to extend the minial UI components, they are exported at your disposal.

// you can import and extend the default minial UI
import TreeMenu, { defaultChildren, ItemComponent } from 'react-simple-tree-menu';

// add custom styling to the list item
<TreeMenu data={treeData}>
    {({ search, items }) => (
        <ul>
            {items.map(({key, ...props}) => (
              <ItemComponent key={key} {...props} />
            ))}
        </ul>
    )}
</TreeMenu>

// add a button to do resetOpenNodes
<TreeMenu data={treeData}>
    {({ search, items, resetOpenNodes }) => (
      <div>
        <button onClick={resetOpenNodes} />
        {defaultChildren({search, items})}
      </div>
    )}
</TreeMenu>

Keyboard browsing

When the tree menu is focused, you can use your keyboard to browse the tree.

• UP: move the focus onto the previous node
• DOWN: move the focus onto the next node
• LEFT: close the current node if it has children and it is open; otherwise move the focus to the parent node
• RIGHT: open the current node if it has children
• ENTER: fire onClick function and set activeKey to current node

Note the difference between the state active and focused. ENTER is equivalent to the onClick event, but focus does not fire onClick.

API

TreeMenu

props	description	type	default
data	Data that defines the structure of the tree. You can nest it as many levels as you want, but note that it might cause performance issue.	{[string]:TreeNode} | TreeNodeInArray[]	-
activeKey	the node matching this key will be active. Note that you need to provide the complete path (e.g. node-level-1/node-level-2/target-node).	string	''
focusKey	the node matching this key will be focused. Note that you need to provide the complete path (e.g. node-level-1/node-level-2/target-node)	string	''
initialActiveKey	set initial state of activeKey. Note that you need to provide the complete path (e.g. node-level-1/node-level-2/target-node).	string	-
initialFocusKey	set initial state of focusKey. Note that you need to provide the complete path (e.g. node-level-1/node-level-2/target-node).	string	-
onClickItem	A callback function that defines the behavior when user clicks on an node	(Item): void	console.warn
debounceTime	debounce time for searching	number	125
openNodes	you can pass an array of node names to control the open state of certain branches	string[]	-
initialOpenNodes	you can pass an array of node names to set some branches open as initial state	string[]	-
locale	you can provide a function that converts label into string	({label, ...other}) => string	({label}) => label
hasSearch	Set to false then children will not have the prop search	boolean	true
cacheSearch	Enable/Disable cache on search	boolean	true
matchSearch	you can define your own search function	({label, searchTerm, ...other}) => boolean	({label, searchTerm}) => isVisible
disableKeyboard	Disable keyboard navigation	boolean	false
children	a render props that provdes two props: search, items and resetOpenNodes	(ChildrenProps) => React.ReactNode	-
keySeparator	an alternative separator for keys in case / regularly occurs in your data	string	'/'

TreeNode

props	description	type	default
label	the rendered text of a Node	string	''
index	a number that defines the rendering order of this node on the same level; this is not needed if data is TreeNode[]	number	-
nodes	a node without this property means that it is the last child of its branch	{[string]:TreeNode} | TreeNode[]	-
...other	User defined props	any	-

TreeNodeInArray

props	description	type	default
key	Node name	string	-
label	the rendered text of a Node	string	''
nodes	a node without this property means that it is the last child of its branch	{[string]:TreeNode} | TreeNode[]	-
...other	User defined props	any	-

Item

props	description	type	default
hasNodes	if a TreeNode is the last node of its branch	boolean	false
isOpen	if it is showing its children	boolean	false
level	the level of the current node (root is zero)	number	0
key	key of a TreeNode	string	-
label	TreeNode label	string	-
...other	User defined props	any	-

ChildrenProps

props	description	type	default
search	A function that takes a string to filter the label of the item (only available if hasSearch is true)	(value: string) => void	-
searchTerm	the search term that is currently applied (only available if hasSearch is true)	string	-
items	An array of TreeMenuItem	TreeMenuItem[]	[]
resetOpenNodes	A function that resets the openNodes, by default it will close all nodes. activeKey is an optional parameter that will highlight the node at the given path. focusKey is also an optional parameter that will set the focus (for keyboard control) to the given path. Both activeKey/focusKey must be provided with the complete path (e.g. node-level-1/node-level-2/target-node). activeKey will not highlight any nodes if not provided. focusKey will default to activeKey if not provided.	(openNodes: string[], activeKey?: string, focusKey?: string) => void	[],'',''

TreeMenuItem

props	description	type	default
hasNodes	if a TreeNode is the last node of its branch	boolean	false
isOpen	if it is showing its children	boolean	false
openNodes	an array of all the open node names	string[]	-
level	the level of the current node (root is zero)	number	0
key	key of a TreeNode	string	-
parent	key of the parent node	string	-
searchTerm	user provided search term	string	-
label	TreeNode label	string	-
active	if current node is being selected	boolean	-
focused	if current node is being focused	boolean	-
onClick	a callback function that is run when the node is clicked	Function	-
toggleNode	a function that toggles the node (only availavble if it has children)	Function	-
...other	User defined props	{[string]: any}	-