Accessibility: Keyboard shortcuts to navigate to/from/in the block's …

…toolbar (#2960)

components/navigable-menu/README.md

@@ -38,3 +38,11 @@ A callback invoked when the menu navigates to one of its children passing the in
 
 - Type: `Function`
 - Required: No
+
+## deep
+
+A boolean to look for navigable children in the direct children or any descendant.
+
+- Type: `Boolean`
+- Required: No
+- default: false

components/navigable-menu/index.js

@@ -26,18 +26,18 @@ class NavigableMenu extends Component {
 	}
 
 	onKeyDown( event ) {
-		const { orientation = 'vertical', onNavigate = noop } = this.props;
+		const { orientation = 'vertical', onNavigate = noop, deep = false } = this.props;
 		if (
 			( orientation === 'vertical' && [ UP, DOWN, TAB ].indexOf( event.keyCode ) === -1 ) ||
 			( orientation === 'horizontal' && [ RIGHT, LEFT, TAB ].indexOf( event.keyCode ) === -1 )
 		) {
 			return;
 		}
-
 		const tabbables = focus.tabbable
 			.find( this.container )
-			.filter( ( node ) => node.parentElement === this.container );
+			.filter( ( node ) => deep || node.parentElement === this.container );
 		const indexOfTabbable = tabbables.indexOf( document.activeElement );
+
 		if ( indexOfTabbable === -1 ) {
 			return;
 		}

editor/block-toolbar/index.js

@@ -8,9 +8,10 @@ import classnames from 'classnames';
 /**
  * WordPress Dependencies
  */
-import { IconButton, Toolbar } from '@wordpress/components';
-import { Component, Children } from '@wordpress/element';
+import { IconButton, Toolbar, NavigableMenu } from '@wordpress/components';
+import { Component, Children, findDOMNode } from '@wordpress/element';
 import { __ } from '@wordpress/i18n';
+import { focus, keycodes } from '@wordpress/utils';
 
 /**
  * Internal Dependencies
@@ -19,19 +20,51 @@ import './style.scss';
 import BlockSwitcher from '../block-switcher';
 import BlockMover from '../block-mover';
 import BlockRightMenu from '../block-settings-menu';
+import { isMac } from '../utils/dom';
+
+/**
+ * Module Constants
+ */
+const { ESCAPE, F10 } = keycodes;
 
 function FirstChild( { children } ) {
 	const childrenArray = Children.toArray( children );
 	return childrenArray[ 0 ] || null;
 }
 
+function metaKeyPressed( event ) {
+	return isMac() ? event.metaKey : ( event.ctrlKey && ! event.altKey );
+}
+
 class BlockToolbar extends Component {
 	constructor() {
 		super( ...arguments );
 		this.toggleMobileControls = this.toggleMobileControls.bind( this );
+		this.bindNode = this.bindNode.bind( this );
+		this.onKeyUp = this.onKeyUp.bind( this );
+		this.onKeyDown = this.onKeyDown.bind( this );
+		this.onToolbarKeyDown = this.onToolbarKeyDown.bind( this );
 		this.state = {
 			showMobileControls: false,
 		};
+
+		// it's not easy to know if the user only clicked on a "meta" key without simultaneously clicking on another key
+		// We keep track of the key counts to ensure it's reliable
+		this.metaCount = 0;
+	}
+
+	componentDidMount() {
+		document.addEventListener( 'keyup', this.onKeyUp );
+		document.addEventListener( 'keydown', this.onKeyDown );
+	}
+
+	componentWillUnmount() {
+		document.removeEventListener( 'keyup', this.onKeyUp );
+		document.removeEventListener( 'keydown', this.onKeyDown );
+	}
+
+	bindNode( ref ) {
+		this.toolbar = findDOMNode( ref );
 	}
 
 	toggleMobileControls() {
@@ -40,6 +73,38 @@ class BlockToolbar extends Component {
 		} ) );
 	}
 
+	onKeyDown( event ) {
+		if ( metaKeyPressed( event ) ) {
+			this.metaCount++;
+		}
+	}
+
+	onKeyUp( event ) {
+		const shouldFocusToolbar = this.metaCount === 1 || ( event.keyCode === F10 && event.altKey );
+		this.metaCount = 0;
+
+		if ( shouldFocusToolbar ) {
+			const tabbables = focus.tabbable.find( this.toolbar );
+			if ( tabbables.length ) {
+				tabbables[ 0 ].focus();
+			}
+		}
+	}
+
+	onToolbarKeyDown( event ) {
+		if ( event.keyCode !== ESCAPE ) {
+			return;
+		}
+
+		// Is there a better way to focus the selected block
+		// TODO: separate focused/selected block state and use Redux actions instead
+		const selectedBlock = document.querySelector( '.editor-visual-editor__block.is-selected .editor-visual-editor__block-edit' );
+		if ( !! selectedBlock ) {
+			event.stopPropagation();
+			selectedBlock.focus();
+		}
+	}
+
 	render() {
 		const { showMobileControls } = this.state;
 		const { uid } = this.props;
@@ -57,8 +122,14 @@ class BlockToolbar extends Component {
 				transitionLeave={ false }
 				component={ FirstChild }
 			>
-				<div className={ toolbarClassname }>
-					<div className="editor-block-toolbar__group">
+				<NavigableMenu
+					className={ toolbarClassname }
+					ref={ this.bindNode }
+					orientation="horizontal"
+					role="toolbar"
+					deep
+				>
+					<div className="editor-block-toolbar__group" onKeyDown={ this.onToolbarKeyDown }>
 						{ ! showMobileControls && [
 							<BlockSwitcher key="switcher" uid={ uid } />,
 							<Slot key="slot" name="Formatting.Toolbar" />,
@@ -80,7 +151,7 @@ class BlockToolbar extends Component {
 							}
 						</Toolbar>
 					</div>
-				</div>
+				</NavigableMenu>
 			</CSSTransitionGroup>
 		);
 	}

editor/utils/dom.js

@@ -86,3 +86,12 @@ export function placeCaretAtEdge( container, start = false ) {
 	sel.addRange( range );
 	container.focus();
 }
+
+/**
+ * Checks whether the user is on MacOS or not
+ *
+ * @return {Boolean}           Is Mac or Not
+ */
+export function isMac() {
+	return window.navigator.platform.toLowerCase().indexOf( 'mac' ) !== -1;
+}

utils/keycodes.js

@@ -8,3 +8,5 @@ export const UP = 38;
 export const RIGHT = 39;
 export const DOWN = 40;
 export const DELETE = 46;
+
+export const F10 = 121;