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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
const { Component, createFactory } = React;
// Localized strings for (devtools/client/locales/en-US/components.properties)
loader.lazyGetter(this, "L10N_COMPONENTS", function () {
return new LocalizationHelper(
"devtools/client/locales/components.properties"
);
});
loader.lazyGetter(this, "EXPAND_LABEL", function () {
return L10N_COMPONENTS.getStr("treeNode.expandButtonTitle");
});
loader.lazyGetter(this, "COLLAPSE_LABEL", function () {
return L10N_COMPONENTS.getStr("treeNode.collapseButtonTitle");
});
// depth
const AUTO_EXPAND_DEPTH = 0;
// Simplied selector targetting elements that can receive the focus,
const FOCUSABLE_SELECTOR = [
"a[href]:not([tabindex='-1'])",
"button:not([disabled], [tabindex='-1'])",
"iframe:not([tabindex='-1'])",
"input:not([disabled], [tabindex='-1'])",
"select:not([disabled], [tabindex='-1'])",
"textarea:not([disabled], [tabindex='-1'])",
"[tabindex]:not([tabindex='-1'])",
].join(", ");
/**
* An arrow that displays whether its node is expanded (▼) or collapsed
* (▶). When its node has no children, it is hidden.
*/
class ArrowExpander extends Component {
static get propTypes() {
return {
expanded: PropTypes.bool,
};
}
shouldComponentUpdate(nextProps) {
return this.props.expanded !== nextProps.expanded;
}
render() {
const { expanded } = this.props;
const classNames = ["arrow"];
const title = expanded ? COLLAPSE_LABEL : EXPAND_LABEL;
if (expanded) {
classNames.push("expanded");
}
return dom.button({
className: classNames.join(" "),
title,
});
}
}
const treeIndent = dom.span({ className: "tree-indent" }, "\u200B");
const treeLastIndent = dom.span(
{ className: "tree-indent tree-last-indent" },
"\u200B"
);
class TreeNode extends Component {
static get propTypes() {
return {
id: PropTypes.any.isRequired,
index: PropTypes.number.isRequired,
depth: PropTypes.number.isRequired,
focused: PropTypes.bool.isRequired,
active: PropTypes.bool.isRequired,
expanded: PropTypes.bool.isRequired,
item: PropTypes.any.isRequired,
isExpandable: PropTypes.bool.isRequired,
onClick: PropTypes.func,
shouldItemUpdate: PropTypes.func,
renderItem: PropTypes.func.isRequired,
};
}
constructor(props) {
super(props);
this.treeNodeRef = React.createRef();
this._onKeyDown = this._onKeyDown.bind(this);
}
componentDidMount() {
// Make sure that none of the focusable elements inside the tree node
// container are tabbable if the tree node is not active. If the tree node
// is active and focus is outside its container, focus on the first
// focusable element inside.
const elms = this.getFocusableElements();
if (this.props.active) {
const doc = this.treeNodeRef.current.ownerDocument;
if (elms.length && !elms.includes(doc.activeElement)) {
elms[0].focus();
}
} else {
elms.forEach(elm => elm.setAttribute("tabindex", "-1"));
}
}
shouldComponentUpdate(nextProps) {
return (
this.props.item !== nextProps.item ||
(this.props.shouldItemUpdate &&
this.props.shouldItemUpdate(this.props.item, nextProps.item)) ||
this.props.focused !== nextProps.focused ||
this.props.expanded !== nextProps.expanded
);
}
/**
* Get a list of all elements that are focusable with a keyboard inside the
* tree node.
*/
getFocusableElements() {
return this.treeNodeRef.current
? Array.from(
this.treeNodeRef.current.querySelectorAll(FOCUSABLE_SELECTOR)
)
: [];
}
/**
* Wrap and move keyboard focus to first/last focusable element inside the
* tree node to prevent the focus from escaping the tree node boundaries.
* element).
*
* @param {DOMNode} current currently focused element
* @param {Boolean} back direction
* @return {Boolean} true there is a newly focused element.
*/
_wrapMoveFocus(current, back) {
const elms = this.getFocusableElements();
let next;
if (elms.length === 0) {
return false;
}
if (back) {
if (elms.indexOf(current) === 0) {
next = elms[elms.length - 1];
next.focus();
}
} else if (elms.indexOf(current) === elms.length - 1) {
next = elms[0];
next.focus();
}
return !!next;
}
_onKeyDown(e) {
const { target, key, shiftKey } = e;
if (key !== "Tab") {
return;
}
const focusMoved = this._wrapMoveFocus(target, shiftKey);
if (focusMoved) {
// Focus was moved to the begining/end of the list, so we need to prevent
// the default focus change that would happen here.
e.preventDefault();
}
e.stopPropagation();
}
render() {
const {
depth,
id,
item,
focused,
active,
expanded,
renderItem,
isExpandable,
} = this.props;
const arrow = isExpandable
? ArrowExpanderFactory({
item,
expanded,
})
: null;
let ariaExpanded;
if (this.props.isExpandable) {
ariaExpanded = false;
}
if (this.props.expanded) {
ariaExpanded = true;
}
const indents = Array.from({ length: depth }, (_, i) => {
if (i == depth - 1) {
return treeLastIndent;
}
return treeIndent;
});
const items = indents.concat(
renderItem(item, depth, focused, arrow, expanded)
);
return dom.div(
{
id,
className: `tree-node${focused ? " focused" : ""}${
active ? " active" : ""
}`,
onClick: this.props.onClick,
onKeyDownCapture: active ? this._onKeyDown : null,
role: "treeitem",
ref: this.treeNodeRef,
"aria-level": depth + 1,
"aria-expanded": ariaExpanded,
"data-expandable": this.props.isExpandable,
},
...items
);
}
}
const ArrowExpanderFactory = createFactory(ArrowExpander);
const TreeNodeFactory = createFactory(TreeNode);
/**
* Create a function that calls the given function `fn` only once per animation
* frame.
*
* @param {Function} fn
* @param {Object} options: object that contains the following properties:
* - {Function} getDocument: A function that return the document
* the component is rendered in.
* @returns {Function}
*/
function oncePerAnimationFrame(fn, { getDocument }) {
let animationId = null;
let argsToPass = null;
return function (...args) {
argsToPass = args;
if (animationId !== null) {
return;
}
const doc = getDocument();
if (!doc) {
return;
}
animationId = doc.defaultView.requestAnimationFrame(() => {
fn.call(this, ...argsToPass);
animationId = null;
argsToPass = null;
});
};
}
/**
* A generic tree component. See propTypes for the public API.
*
* This tree component doesn't make any assumptions about the structure of your
* tree data. Whether children are computed on demand, or stored in an array in
* the parent's `_children` property, it doesn't matter. We only require the
* implementation of `getChildren`, `getRoots`, `getParent`, and `isExpanded`
* functions.
*
* This tree component is well tested and reliable. See the tests in ./tests
* and its usage in the memory panel in mozilla-central.
*
* This tree component doesn't make any assumptions about how to render items in
* the tree. You provide a `renderItem` function, and this component will ensure
* that only those items whose parents are expanded and which are visible in the
* viewport are rendered. The `renderItem` function could render the items as a
* "traditional" tree or as rows in a table or anything else. It doesn't
* restrict you to only one certain kind of tree.
*
* The tree comes with basic styling for the indent, the arrow, as well as
* hovered and focused styles which can be override in CSS.
*
* ### Example Usage
*
* Suppose we have some tree data where each item has this form:
*
* {
* id: Number,
* label: String,
* parent: Item or null,
* children: Array of child items,
* expanded: bool,
* }
*
* Here is how we could render that data with this component:
*
* class MyTree extends Component {
* static get propTypes() {
* // The root item of the tree, with the form described above.
* return {
* root: PropTypes.object.isRequired
* };
* },
*
* render() {
* return Tree({
* getRoots: () => [this.props.root],
*
* getParent: item => item.parent,
* getChildren: item => item.children,
* getKey: item => item.id,
* isExpanded: item => item.expanded,
*
* renderItem: (item, depth, isFocused, arrow, isExpanded) => {
* let className = "my-tree-item";
* if (isFocused) {
* className += " focused";
* }
* return dom.div({
* className,
* },
* arrow,
* // And here is the label for this item.
* dom.span({ className: "my-tree-item-label" }, item.label)
* );
* },
*
* onExpand: item => dispatchExpandActionToRedux(item),
* onCollapse: item => dispatchCollapseActionToRedux(item),
* });
* }
* }
*/
class Tree extends Component {
static get propTypes() {
return {
// Required props
// A function to get an item's parent, or null if it is a root.
//
// Type: getParent(item: Item) -> Maybe<Item>
//
// Example:
//
// // The parent of this item is stored in its `parent` property.
// getParent: item => item.parent
getParent: PropTypes.func.isRequired,
// A function to get an item's children.
//
// Type: getChildren(item: Item) -> [Item]
//
// Example:
//
// // This item's children are stored in its `children` property.
// getChildren: item => item.children
getChildren: PropTypes.func.isRequired,
// A function to check if the tree node for the item should be updated.
//
// Type: shouldItemUpdate(prevItem: Item, nextItem: Item) -> Boolean
//
// Example:
//
// // This item should be updated if it's type is a long string
// shouldItemUpdate: (prevItem, nextItem) =>
// nextItem.type === "longstring"
shouldItemUpdate: PropTypes.func,
// A function which takes an item and ArrowExpander component instance and
// returns a component, or text, or anything else that React considers
// renderable.
//
// Type: renderItem(item: Item,
// depth: Number,
// isFocused: Boolean,
// arrow: ReactComponent,
// isExpanded: Boolean) -> ReactRenderable
//
// Example:
//
// renderItem: (item, depth, isFocused, arrow, isExpanded) => {
// let className = "my-tree-item";
// if (isFocused) {
// className += " focused";
// }
// return dom.div(
// {
// className,
// style: { marginLeft: depth * 10 + "px" }
// },
// arrow,
// dom.span({ className: "my-tree-item-label" }, item.label)
// );
// },
renderItem: PropTypes.func.isRequired,
// A function which returns the roots of the tree (forest).
//
// Type: getRoots() -> [Item]
//
// Example:
//
// // In this case, we only have one top level, root item. You could
// // return multiple items if you have many top level items in your
// // tree.
// getRoots: () => [this.props.rootOfMyTree]
getRoots: PropTypes.func.isRequired,
// A function to get a unique key for the given item. This helps speed up
// React's rendering a *TON*.
//
// Type: getKey(item: Item) -> String
//
// Example:
//
// getKey: item => `my-tree-item-${item.uniqueId}`
getKey: PropTypes.func.isRequired,
// A function to get whether an item is expanded or not. If an item is not
// expanded, then it must be collapsed.
//
// Type: isExpanded(item: Item) -> Boolean
//
// Example:
//
// isExpanded: item => item.expanded,
isExpanded: PropTypes.func.isRequired,
// Optional props
// The currently focused item, if any such item exists.
focused: PropTypes.any,
// Handle when a new item is focused.
onFocus: PropTypes.func,
// The depth to which we should automatically expand new items.
autoExpandDepth: PropTypes.number,
// Should auto expand all new items or just the new items under the first
// root item.
autoExpandAll: PropTypes.bool,
// Auto expand a node only if number of its children
// are less than autoExpandNodeChildrenLimit
autoExpandNodeChildrenLimit: PropTypes.number,
// Note: the two properties below are mutually exclusive. Only one of the
// label properties is necessary.
// ID of an element whose textual content serves as an accessible label
// for a tree.
labelledby: PropTypes.string,
// Accessibility label for a tree widget.
label: PropTypes.string,
// Optional event handlers for when items are expanded or collapsed.
// Useful for dispatching redux events and updating application state,
// maybe lazily loading subtrees from a worker, etc.
//
// Type:
// onExpand(item: Item)
// onCollapse(item: Item)
//
// Example:
//
// onExpand: item => dispatchExpandActionToRedux(item)
onExpand: PropTypes.func,
onCollapse: PropTypes.func,
// The currently active (keyboard) item, if any such item exists.
active: PropTypes.any,
// Optional event handler called with the current focused node when the
// Enter key is pressed. Can be useful to allow further keyboard actions
// within the tree node.
onActivate: PropTypes.func,
isExpandable: PropTypes.func,
// Additional classes to add to the root element.
className: PropTypes.string,
// style object to be applied to the root element.
style: PropTypes.object,
// Prevents blur when Tree loses focus
preventBlur: PropTypes.bool,
initiallyExpanded: PropTypes.func,
};
}
static get defaultProps() {
return {
autoExpandDepth: AUTO_EXPAND_DEPTH,
autoExpandAll: true,
};
}
constructor(props) {
super(props);
this.state = {
autoExpanded: new Set(),
};
this.treeRef = React.createRef();
const opaf = fn =>
oncePerAnimationFrame(fn, {
getDocument: () =>
this.treeRef.current && this.treeRef.current.ownerDocument,
});
this._onExpand = opaf(this._onExpand).bind(this);
this._onCollapse = opaf(this._onCollapse).bind(this);
this._focusPrevNode = opaf(this._focusPrevNode).bind(this);
this._focusNextNode = opaf(this._focusNextNode).bind(this);
this._focusParentNode = opaf(this._focusParentNode).bind(this);
this._focusFirstNode = opaf(this._focusFirstNode).bind(this);
this._focusLastNode = opaf(this._focusLastNode).bind(this);
this._autoExpand = this._autoExpand.bind(this);
this._preventArrowKeyScrolling = this._preventArrowKeyScrolling.bind(this);
this._preventEvent = this._preventEvent.bind(this);
this._dfs = this._dfs.bind(this);
this._dfsFromRoots = this._dfsFromRoots.bind(this);
this._focus = this._focus.bind(this);
this._activate = this._activate.bind(this);
this._scrollNodeIntoView = this._scrollNodeIntoView.bind(this);
this._onBlur = this._onBlur.bind(this);
this._onKeyDown = this._onKeyDown.bind(this);
this._nodeIsExpandable = this._nodeIsExpandable.bind(this);
}
componentDidMount() {
this._autoExpand();
if (this.props.focused) {
this._scrollNodeIntoView(this.props.focused);
}
}
UNSAFE_componentWillReceiveProps() {
this._autoExpand();
}
componentDidUpdate(prevProps) {
if (this.props.focused && prevProps.focused !== this.props.focused) {
this._scrollNodeIntoView(this.props.focused);
}
}
_autoExpand() {
const { autoExpandDepth, autoExpandNodeChildrenLimit, initiallyExpanded } =
this.props;
if (!autoExpandDepth && !initiallyExpanded) {
return;
}
// Automatically expand the first autoExpandDepth levels for new items. Do
// not use the usual DFS infrastructure because we don't want to ignore
// collapsed nodes. Any initially expanded items will be expanded regardless
// of how deep they are.
const autoExpand = (item, currentDepth) => {
const initial = initiallyExpanded && initiallyExpanded(item);
if (!initial && currentDepth >= autoExpandDepth) {
return;
}
const children = this.props.getChildren(item);
if (
!initial &&
autoExpandNodeChildrenLimit &&
children.length > autoExpandNodeChildrenLimit
) {
return;
}
if (!this.state.autoExpanded.has(item)) {
this.props.onExpand(item);
this.state.autoExpanded.add(item);
}
const length = children.length;
for (let i = 0; i < length; i++) {
autoExpand(children[i], currentDepth + 1);
}
};
const roots = this.props.getRoots();
const length = roots.length;
if (this.props.autoExpandAll) {
for (let i = 0; i < length; i++) {
autoExpand(roots[i], 0);
}
} else if (length != 0) {
autoExpand(roots[0], 0);
if (initiallyExpanded) {
for (let i = 1; i < length; i++) {
if (initiallyExpanded(roots[i])) {
autoExpand(roots[i], 0);
}
}
}
}
}
_preventArrowKeyScrolling(e) {
switch (e.key) {
case "ArrowUp":
case "ArrowDown":
case "ArrowLeft":
case "ArrowRight":
this._preventEvent(e);
break;
}
}
_preventEvent(e) {
e.preventDefault();
e.stopPropagation();
if (e.nativeEvent) {
if (e.nativeEvent.preventDefault) {
e.nativeEvent.preventDefault();
}
if (e.nativeEvent.stopPropagation) {
e.nativeEvent.stopPropagation();
}
}
}
/**
* Perform a pre-order depth-first search from item.
*/
_dfs(item, maxDepth = Infinity, traversal = [], _depth = 0) {
traversal.push({ item, depth: _depth });
if (!this.props.isExpanded(item)) {
return traversal;
}
const nextDepth = _depth + 1;
if (nextDepth > maxDepth) {
return traversal;
}
const children = this.props.getChildren(item);
const length = children.length;
for (let i = 0; i < length; i++) {
this._dfs(children[i], maxDepth, traversal, nextDepth);
}
return traversal;
}
/**
* Perform a pre-order depth-first search over the whole forest.
*/
_dfsFromRoots(maxDepth = Infinity) {
const traversal = [];
const roots = this.props.getRoots();
const length = roots.length;
for (let i = 0; i < length; i++) {
this._dfs(roots[i], maxDepth, traversal);
}
return traversal;
}
/**
* Expands current row.
*
* @param {Object} item
* @param {Boolean} expandAllChildren
*/
_onExpand(item, expandAllChildren) {
if (this.props.onExpand) {
this.props.onExpand(item);
if (expandAllChildren) {
const children = this._dfs(item);
const length = children.length;
for (let i = 0; i < length; i++) {
this.props.onExpand(children[i].item);
}
}
}
}
/**
* Collapses current row.
*
* @param {Object} item
*/
_onCollapse(item) {
if (this.props.onCollapse) {
this.props.onCollapse(item);
}
}
/**
* Sets the passed in item to be the focused item.
*
* @param {Object|undefined} item
* The item to be focused, or undefined to focus no item.
*
* @param {Object|undefined} options
* An options object which can contain:
* - dir: "up" or "down" to indicate if we should scroll the element
* to the top or the bottom of the scrollable container when
* the element is off canvas.
*/
_focus(item, options = {}) {
const { preventAutoScroll } = options;
if (item && !preventAutoScroll) {
this._scrollNodeIntoView(item, options);
}
if (this.props.active != undefined) {
this._activate(undefined);
const doc = this.treeRef.current && this.treeRef.current.ownerDocument;
if (this.treeRef.current !== doc.activeElement) {
this.treeRef.current.focus();
}
}
if (this.props.onFocus) {
this.props.onFocus(item);
}
}
/**
* Sets the passed in item to be the active item.
*
* @param {Object|undefined} item
* The item to be activated, or undefined to activate no item.
*/
_activate(item) {
if (this.props.onActivate) {
this.props.onActivate(item);
}
}
/**
* Sets the passed in item to be the focused item.
*
* @param {Object|undefined} item
* The item to be scrolled to.
*
* @param {Object|undefined} options
* An options object which can contain:
* - dir: "up" or "down" to indicate if we should scroll the element
* to the top or the bottom of the scrollable container when
* the element is off canvas.
*/
_scrollNodeIntoView(item, options = {}) {
if (item !== undefined) {
const treeElement = this.treeRef.current;
const doc = treeElement && treeElement.ownerDocument;
const element = doc.getElementById(this.props.getKey(item));
if (element) {
const { top, bottom } = element.getBoundingClientRect();
const closestScrolledParent = node => {
if (node == null) {
return null;
}
if (node.scrollHeight > node.clientHeight) {
return node;
}
return closestScrolledParent(node.parentNode);
};
const scrolledParent = closestScrolledParent(treeElement);
const scrolledParentRect = scrolledParent
? scrolledParent.getBoundingClientRect()
: null;
const isVisible =
!scrolledParent ||
(top >= scrolledParentRect.top &&
bottom <= scrolledParentRect.bottom);
if (!isVisible) {
const { alignTo } = options;
const scrollToTop = alignTo
? alignTo === "top"
: !scrolledParentRect || top < scrolledParentRect.top;
element.scrollIntoView(scrollToTop);
}
}
}
}
/**
* Sets the state to have no focused item.
*/
_onBlur(e) {
if (this.props.active != undefined) {
const { relatedTarget } = e;
if (!this.treeRef.current.contains(relatedTarget)) {
this._activate(undefined);
}
} else if (!this.props.preventBlur) {
this._focus(undefined);
}
}
/**
* Handles key down events in the tree's container.
*
* @param {Event} e
*/
// eslint-disable-next-line complexity
_onKeyDown(e) {
if (this.props.focused == null) {
return;
}
// Allow parent nodes to use navigation arrows with modifiers.
if (e.altKey || e.ctrlKey || e.shiftKey || e.metaKey) {
return;
}
this._preventArrowKeyScrolling(e);
const doc = this.treeRef.current && this.treeRef.current.ownerDocument;
switch (e.key) {
case "ArrowUp":
this._focusPrevNode();
return;
case "ArrowDown":
this._focusNextNode();
return;
case "ArrowLeft":
if (
this.props.isExpanded(this.props.focused) &&
this._nodeIsExpandable(this.props.focused)
) {
this._onCollapse(this.props.focused);
} else {
this._focusParentNode();
}
return;
case "ArrowRight":
if (
this._nodeIsExpandable(this.props.focused) &&
!this.props.isExpanded(this.props.focused)
) {
this._onExpand(this.props.focused);
} else {
this._focusNextNode();
}
return;
case "Home":
this._focusFirstNode();
return;
case "End":
this._focusLastNode();
return;
case "Enter":
case " ":
if (this.treeRef.current === doc.activeElement) {
this._preventEvent(e);
if (this.props.active !== this.props.focused) {
this._activate(this.props.focused);
}
}
return;
case "Escape":
this._preventEvent(e);
if (this.props.active != undefined) {
this._activate(undefined);
}
if (this.treeRef.current !== doc.activeElement) {
this.treeRef.current.focus();
}
}
}
/**
* Sets the previous node relative to the currently focused item, to focused.
*/
_focusPrevNode() {
// Start a depth first search and keep going until we reach the currently
// focused node. Focus the previous node in the DFS, if it exists. If it
// doesn't exist, we're at the first node already.
let prev;
const traversal = this._dfsFromRoots();
const length = traversal.length;
for (let i = 0; i < length; i++) {
const item = traversal[i].item;
if (item === this.props.focused) {
break;
}
prev = item;
}
if (prev === undefined) {
return;
}
this._focus(prev, { alignTo: "top" });
}
/**
* Handles the down arrow key which will focus either the next child
* or sibling row.
*/
_focusNextNode() {
// Start a depth first search and keep going until we reach the currently
// focused node. Focus the next node in the DFS, if it exists. If it
// doesn't exist, we're at the last node already.
const traversal = this._dfsFromRoots();
const length = traversal.length;
let i = 0;
while (i < length) {
if (traversal[i].item === this.props.focused) {
break;
}
i++;
}
if (i + 1 < traversal.length) {
this._focus(traversal[i + 1].item, { alignTo: "bottom" });
}
}
/**
* Handles the left arrow key, going back up to the current rows'
* parent row.
*/
_focusParentNode() {
const parent = this.props.getParent(this.props.focused);
if (!parent) {
this._focusPrevNode(this.props.focused);
return;
}
this._focus(parent, { alignTo: "top" });
}
_focusFirstNode() {
const traversal = this._dfsFromRoots();
this._focus(traversal[0].item, { alignTo: "top" });
}
_focusLastNode() {
const traversal = this._dfsFromRoots();
const lastIndex = traversal.length - 1;
this._focus(traversal[lastIndex].item, { alignTo: "bottom" });
}
_nodeIsExpandable(item) {
return this.props.isExpandable
? this.props.isExpandable(item)
: !!this.props.getChildren(item).length;
}
render() {
const traversal = this._dfsFromRoots();
const { active, focused } = this.props;
const nodes = traversal.map((v, i) => {
const { item, depth } = traversal[i];
const key = this.props.getKey(item, i);
const focusedKey = focused ? this.props.getKey(focused, i) : null;
return TreeNodeFactory({
// We make a key unique depending on whether the tree node is in active
// or inactive state to make sure that it is actually replaced and the
// tabbable state is reset.
key: `${key}-${active === item ? "active" : "inactive"}`,
id: key,
index: i,
item,
depth,
shouldItemUpdate: this.props.shouldItemUpdate,
renderItem: this.props.renderItem,
focused: focusedKey === key,
active: active === item,
expanded: this.props.isExpanded(item),
isExpandable: this._nodeIsExpandable(item),
onExpand: this._onExpand,
onCollapse: this._onCollapse,
onClick: e => {
// We can stop the propagation since click handler on the node can be
// created in `renderItem`.
e.stopPropagation();
// Since the user just clicked the node, there's no need to check if
// it should be scrolled into view.
this._focus(item, { preventAutoScroll: true });
if (this.props.isExpanded(item)) {
this.props.onCollapse(item, e.altKey);
} else {
this.props.onExpand(item, e.altKey);
}
// Focus should always remain on the tree container itself.
this.treeRef.current.focus();
},
});
});
const style = Object.assign({}, this.props.style || {});
return dom.div(
{
className: `tree ${this.props.className ? this.props.className : ""}`,
ref: this.treeRef,
role: "tree",
tabIndex: "0",
onKeyDown: this._onKeyDown,
onKeyPress: this._preventArrowKeyScrolling,
onKeyUp: this._preventArrowKeyScrolling,
onFocus: ({ nativeEvent }) => {
if (focused || !nativeEvent || !this.treeRef.current) {
return;
}
const { explicitOriginalTarget } = nativeEvent;
// Only set default focus to the first tree node if the focus came
// from outside the tree (e.g. by tabbing to the tree from other
// external elements).
if (
explicitOriginalTarget !== this.treeRef.current &&
!this.treeRef.current.contains(explicitOriginalTarget)
) {
this._focus(traversal[0].item);
}
},
onBlur: this._onBlur,
"aria-label": this.props.label,
"aria-labelledby": this.props.labelledby,
"aria-activedescendant": focused && this.props.getKey(focused),
style,
},
nodes
);
}
}
module.exports = Tree;