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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
+ * file, You can obtain one at <http://mozilla.org/MPL/2.0/>. */
+
+"use strict";
+
+const React = require("devtools/client/shared/vendor/react");
+const { Component, createFactory } = React;
+const dom = require("devtools/client/shared/vendor/react-dom-factories");
+const PropTypes = require("devtools/client/shared/vendor/react-prop-types");
+
+// depth
+const AUTO_EXPAND_DEPTH = 0;
+
+// Simplied selector targetting elements that can receive the focus,
+// full version at https://stackoverflow.com/questions/1599660.
+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, nextState) {
+ return this.props.expanded !== nextProps.expanded;
+ }
+
+ render() {
+ const { expanded } = this.props;
+
+ const classNames = ["arrow"];
+ if (expanded) {
+ classNames.push("expanded");
+ }
+ return dom.button({
+ className: classNames.join(" "),
+ });
+ }
+}
+
+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 > 0 && !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 performance and memory panels 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({
+ * itemHeight: 20, // px
+ *
+ * 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.bool,
+ };
+ }
+
+ 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);
+ }
+ }
+
+ componentWillReceiveProps(nextProps) {
+ this._autoExpand();
+ }
+
+ componentDidUpdate(prevProps, prevState) {
+ 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);
+ 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: focused === item,
+ 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;