Add arrow key controls to emoji and reaction pickers

cypress/e2e/threads/threads.spec.ts

@@ -174,7 +174,7 @@ describe("Threads", () => {
             .click({ force: true }); // Cypress has no ability to hover
         cy.get(".mx_EmojiPicker").within(() => {
             cy.get('input[type="text"]').type("wave");
-            cy.contains('[role="menuitem"]', "👋").click();
+            cy.contains('[role="gridcell"]', "👋").click();
         });
 
         cy.get(".mx_ThreadView").within(() => {

res/css/views/emojipicker/_EmojiPicker.pcss

@@ -179,6 +179,14 @@ limitations under the License.
     list-style: none;
     width: 38px;
     cursor: pointer;
+
+    &:focus-within {
+        background-color: $focus-bg-color;
+    }
+}
+
+.mx_EmojiPicker_body .mx_EmojiPicker_item_wrapper[tabindex="0"] .mx_EmojiPicker_item {
+    background-color: $focus-bg-color;
 }
 
 .mx_EmojiPicker_item {

src/accessibility/RovingTabIndex.tsx

@@ -61,7 +61,7 @@ export interface IState {
     refs: Ref[];
 }
 
-interface IContext {
+export interface IContext {
     state: IState;
     dispatch: Dispatch<IAction>;
 }
@@ -80,7 +80,7 @@ export enum Type {
     SetFocus = "SET_FOCUS",
 }
 
-interface IAction {
+export interface IAction {
     type: Type;
     payload: {
         ref: Ref;
@@ -160,7 +160,7 @@ interface IProps {
     handleUpDown?: boolean;
     handleLeftRight?: boolean;
     children(renderProps: { onKeyDownHandler(ev: React.KeyboardEvent): void }): ReactNode;
-    onKeyDown?(ev: React.KeyboardEvent, state: IState): void;
+    onKeyDown?(ev: React.KeyboardEvent, state: IState, dispatch: Dispatch<IAction>): void;
 }
 
 export const findSiblingElement = (
@@ -199,7 +199,7 @@ export const RovingTabIndexProvider: React.FC<IProps> = ({
     const onKeyDownHandler = useCallback(
         (ev: React.KeyboardEvent) => {
             if (onKeyDown) {
-                onKeyDown(ev, context.state);
+                onKeyDown(ev, context.state, context.dispatch);
                 if (ev.defaultPrevented) {
                     return;
                 }

src/accessibility/roving/RovingAccessibleButton.tsx

@@ -22,10 +22,17 @@ import { Ref } from "./types";
 
 interface IProps extends Omit<React.ComponentProps<typeof AccessibleButton>, "inputRef" | "tabIndex"> {
     inputRef?: Ref;
+    focusOnMouseOver?: boolean;
 }
 
 // Wrapper to allow use of useRovingTabIndex for simple AccessibleButtons outside of React Functional Components.
-export const RovingAccessibleButton: React.FC<IProps> = ({ inputRef, onFocus, ...props }) => {
+export const RovingAccessibleButton: React.FC<IProps> = ({
+    inputRef,
+    onFocus,
+    onMouseOver,
+    focusOnMouseOver,
+    ...props
+}) => {
     const [onFocusInternal, isActive, ref] = useRovingTabIndex(inputRef);
     return (
         <AccessibleButton
@@ -34,6 +41,10 @@ export const RovingAccessibleButton: React.FC<IProps> = ({ inputRef, onFocus, ..
                 onFocusInternal();
                 onFocus?.(event);
             }}
+            onMouseOver={(event: React.MouseEvent) => {
+                if (focusOnMouseOver) onFocusInternal();
+                onMouseOver?.(event);
+            }}
             inputRef={ref}
             tabIndex={isActive ? 0 : -1}
         />

src/components/structures/ContextMenu.tsx

@@ -148,7 +148,7 @@ export default class ContextMenu extends React.PureComponent<React.PropsWithChil
 
         const first =
             element.querySelector<HTMLElement>('[role^="menuitem"]') ||
-            element.querySelector<HTMLElement>("[tab-index]");
+            element.querySelector<HTMLElement>("[tabindex]");
 
         if (first) {
             first.focus();

src/components/views/elements/LazyRenderList.tsx

@@ -73,6 +73,7 @@ interface IProps<T> {
 
     element?: string;
     className?: string;
+    role?: string;
 }
 
 interface IState {
@@ -128,6 +129,7 @@ export default class LazyRenderList<T = any> extends React.Component<IProps<T>,
         const elementProps = {
             style: { paddingTop: `${paddingTop}px`, paddingBottom: `${paddingBottom}px` },
             className: this.props.className,
+            role: this.props.role,
         };
         return React.createElement(element, elementProps, renderedItems.map(renderItem));
     }

src/components/views/emojipicker/Category.tsx

@@ -21,6 +21,7 @@ import { CATEGORY_HEADER_HEIGHT, EMOJI_HEIGHT, EMOJIS_PER_ROW } from "./EmojiPic
 import LazyRenderList from "../elements/LazyRenderList";
 import { DATA_BY_CATEGORY, IEmoji } from "../../../emoji";
 import Emoji from "./Emoji";
+import { ButtonEvent } from "../elements/AccessibleButton";
 
 const OVERFLOW_ROWS = 3;
 
@@ -42,18 +43,31 @@ interface IProps {
     heightBefore: number;
     viewportHeight: number;
     scrollTop: number;
-    onClick(emoji: IEmoji): void;
+    onClick(ev: ButtonEvent, emoji: IEmoji): void;
     onMouseEnter(emoji: IEmoji): void;
     onMouseLeave(emoji: IEmoji): void;
     isEmojiDisabled?: (unicode: string) => boolean;
 }
 
+function hexEncode(str: string): string {
+    let hex: string;
+    let i: number;
+
+    let result = "";
+    for (i = 0; i < str.length; i++) {
+        hex = str.charCodeAt(i).toString(16);
+        result += ("000" + hex).slice(-4);
+    }
+
+    return result;
+}
+
 class Category extends React.PureComponent<IProps> {
     private renderEmojiRow = (rowIndex: number): JSX.Element => {
         const { onClick, onMouseEnter, onMouseLeave, selectedEmojis, emojis } = this.props;
         const emojisForRow = emojis.slice(rowIndex * 8, (rowIndex + 1) * 8);
         return (
-            <div key={rowIndex}>
+            <div key={rowIndex} role="row">
                 {emojisForRow.map((emoji) => (
                     <Emoji
                         key={emoji.hexcode}
@@ -63,6 +77,8 @@ class Category extends React.PureComponent<IProps> {
                         onMouseEnter={onMouseEnter}
                         onMouseLeave={onMouseLeave}
                         disabled={this.props.isEmojiDisabled?.(emoji.unicode)}
+                        id={`mx_EmojiPicker_item_${this.props.id}_${hexEncode(emoji.unicode)}`}
+                        role="gridcell"
                     />
                 ))}
             </div>
@@ -101,7 +117,6 @@ class Category extends React.PureComponent<IProps> {
             >
                 <h2 className="mx_EmojiPicker_category_label">{name}</h2>
                 <LazyRenderList
-                    element="ul"
                     className="mx_EmojiPicker_list"
                     itemHeight={EMOJI_HEIGHT}
                     items={rows}
@@ -110,6 +125,7 @@ class Category extends React.PureComponent<IProps> {
                     overflowItems={OVERFLOW_ROWS}
                     overflowMargin={0}
                     renderItem={this.renderEmojiRow}
+                    role="grid"
                 />
             </section>
         );

src/components/views/emojipicker/Emoji.tsx

@@ -17,36 +17,40 @@ limitations under the License.
 
 import React from "react";
 
-import { MenuItem } from "../../structures/ContextMenu";
 import { IEmoji } from "../../../emoji";
+import { ButtonEvent } from "../elements/AccessibleButton";
+import { RovingAccessibleButton } from "../../../accessibility/RovingTabIndex";
 
 interface IProps {
     emoji: IEmoji;
     selectedEmojis?: Set<string>;
-    onClick(emoji: IEmoji): void;
+    onClick(ev: ButtonEvent, emoji: IEmoji): void;
     onMouseEnter(emoji: IEmoji): void;
     onMouseLeave(emoji: IEmoji): void;
     disabled?: boolean;
+    id?: string;
+    role?: string;
 }
 
 class Emoji extends React.PureComponent<IProps> {
     public render(): React.ReactNode {
         const { onClick, onMouseEnter, onMouseLeave, emoji, selectedEmojis } = this.props;
-        const isSelected = selectedEmojis && selectedEmojis.has(emoji.unicode);
+        const isSelected = selectedEmojis?.has(emoji.unicode);
         return (
-            <MenuItem
-                element="li"
-                onClick={() => onClick(emoji)}
+            <RovingAccessibleButton
+                id={this.props.id}
+                onClick={(ev) => onClick(ev, emoji)}
                 onMouseEnter={() => onMouseEnter(emoji)}
                 onMouseLeave={() => onMouseLeave(emoji)}
                 className="mx_EmojiPicker_item_wrapper"
-                label={emoji.unicode}
                 disabled={this.props.disabled}
+                role={this.props.role}
+                focusOnMouseOver
             >
                 <div className={`mx_EmojiPicker_item ${isSelected ? "mx_EmojiPicker_item_selected" : ""}`}>
                     {emoji.unicode}
                 </div>
-            </MenuItem>
+            </RovingAccessibleButton>
         );
     }
 }