Components: Add ItemGroup and Item

packages/components/src/ui/item-group/context.ts

@@ -0,0 +1,11 @@
+/**
+ * WordPress dependencies
+ */
+import { createContext, useContext } from '@wordpress/element';
+
+export const ItemGroupContext = createContext( { size: 'medium' } as {
+	spacedAround: boolean;
+	size: 'small' | 'medium' | 'large';
+} );
+
+export const useItemGroupContext = () => useContext( ItemGroupContext );

packages/components/src/ui/item-group/index.ts

@@ -0,0 +1,2 @@
+export { default as Item } from './item';
+export { default as ItemGroup } from './item-group';

packages/components/src/ui/item-group/item-group.tsx

@@ -0,0 +1,35 @@
+/**
+ * Internal dependencies
+ */
+import type { PolymorphicComponentProps } from '../context';
+// eslint-disable-next-line no-duplicate-imports
+import { contextConnect } from '../context';
+import { useItemGroup } from './use-item-group';
+// eslint-disable-next-line no-duplicate-imports
+import type { Props } from './use-item-group';
+import { ItemGroupContext, useItemGroupContext } from './context';
+import { View } from '../../view';
+
+function ItemGroup( props: PolymorphicComponentProps< Props, 'div' > ) {
+	const { bordered, separated, size: sizeProp, ...otherProps } = useItemGroup(
+		props
+	);
+
+	const { size: contextSize } = useItemGroupContext();
+
+	const spacedAround = ! bordered && ! separated;
+	const size = sizeProp || contextSize;
+
+	const contextValue = {
+		spacedAround,
+		size,
+	};
+
+	return (
+		<ItemGroupContext.Provider value={ contextValue }>
+			<View { ...otherProps } />
+		</ItemGroupContext.Provider>
+	);
+}
+
+export default contextConnect( ItemGroup, 'ItemGroup' );

packages/components/src/ui/item-group/item.ts

@@ -0,0 +1,11 @@
+/**
+ * Internal dependencies
+ */
+import { createComponent } from '../utils';
+import { useItem } from './use-item';
+
+export default createComponent( {
+	useHook: useItem,
+	as: 'div',
+	name: 'Item',
+} );

packages/components/src/ui/item-group/stories/index.js

@@ -0,0 +1,53 @@
+/* eslint-disable no-alert */
+/* globals alert */
+/**
+ * Internal dependencies
+ */
+import { ItemGroup, Item } from '..';
+import { Popover } from '../../popover';
+import Button from '../../../button';
+
+export default {
+	component: ItemGroup,
+	title: 'Components (Experimental)/ItemGroup',
+};
+
+export const _default = () => (
+	<ItemGroup css={ { width: '350px' } } bordered>
+		<Item action onClick={ () => alert( 'WordPress.org' ) }>
+			Code is Poetry — Click me!
+		</Item>
+		<Item action onClick={ () => alert( 'WordPress.org' ) }>
+			Code is Poetry — Click me!
+		</Item>
+		<Item action onClick={ () => alert( 'WordPress.org' ) }>
+			Code is Poetry — Click me!
+		</Item>
+		<Item action onClick={ () => alert( 'WordPress.org' ) }>
+			Code is Poetry — Click me!
+		</Item>
+	</ItemGroup>
+);
+
+export const dropdown = () => (
+	<Popover
+		css={ { width: '350px' } }
+		trigger={ <Button>Open Popover</Button> }
+	>
+		<ItemGroup css={ { padding: 4 } }>
+			<Item action onClick={ () => alert( 'WordPress.org' ) }>
+				Code is Poetry — Click me!
+			</Item>
+			<Item action onClick={ () => alert( 'WordPress.org' ) }>
+				Code is Poetry — Click me!
+			</Item>
+			<Item action onClick={ () => alert( 'WordPress.org' ) }>
+				Code is Poetry — Click me!
+			</Item>
+			<Item action onClick={ () => alert( 'WordPress.org' ) }>
+				Code is Poetry — Click me!
+			</Item>
+		</ItemGroup>
+	</Popover>
+);
+/* eslint-enable no-alert */

packages/components/src/ui/item-group/styles.ts

@@ -0,0 +1,93 @@
+/**
+ * External dependencies
+ */
+import { css } from 'emotion';
+
+/**
+ * Internal dependencies
+ */
+import { CONFIG } from '../../utils';
+import COLORS from '../../utils/colors-values';
+
+export const unstyledButton = css`
+	appearance: none;
+	border: 1px solid transparent;
+	cursor: pointer;
+	background: none;
+	text-align: left;
+
+	&:hover {
+		color: ${ COLORS.admin.theme };
+	}
+
+	&:focus {
+		background-color: transparent;
+		color: ${ COLORS.admin.theme };
+		border-color: ${ COLORS.admin.theme };
+		outline: 3px solid transparent;
+	}
+`;
+
+export const item = css`
+	width: 100%;
+	display: block;
+`;
+
+export const bordered = css`
+	border: 1px solid ${ CONFIG.surfaceBorderColor };
+`;
+
+export const separated = css`
+	> *:not( marquee ) {
+		border-bottom: 1px solid ${ CONFIG.surfaceBorderColor };
+	}
+
+	> *:last-child:not( :focus ) {
+		border-bottom-color: transparent;
+	}
+`;
+
+const borderRadius = CONFIG.controlBorderRadius;
+
+export const spacedAround = css`
+	border-radius: ${ borderRadius };
+`;
+
+export const rounded = css`
+	border-radius: ${ borderRadius };
+
+	> *:first-child {
+		border-top-left-radius: ${ borderRadius };
+		border-top-right-radius: ${ borderRadius };
+	}
+
+	> *:last-child {
+		border-bottom-left-radius: ${ borderRadius };
+		border-bottom-right-radius: ${ borderRadius };
+	}
+`;
+
+const baseFontHeight = `calc(${ CONFIG.fontSize } * ${ CONFIG.fontLineHeightBase })`;
+
+/*
+ * Math:
+ * - Use the desired height as the base value
+ * - Subtract the computed height of (default) text
+ * - Subtract the effects of border
+ * - Divide the calculated number by 2, in order to get an individual top/bottom padding
+ */
+const paddingY = `calc((${ CONFIG.controlHeight } - ${ baseFontHeight } - 2px) / 2)`;
+const paddingYSmall = `calc((${ CONFIG.controlHeightSmall } - ${ baseFontHeight } - 2px) / 2)`;
+const paddingYLarge = `calc((${ CONFIG.controlHeightLarge } - ${ baseFontHeight } - 2px) / 2)`;
+
+export const itemSizes = {
+	small: css`
+		padding: ${ paddingYSmall }, ${ CONFIG.controlPaddingXSmall };
+	`,
+	medium: css`
+		padding: ${ paddingY }, ${ CONFIG.controlPaddingX };
+	`,
+	large: css`
+		padding: ${ paddingYLarge }, ${ CONFIG.controlPaddingXLarge };
+	`,
+};

packages/components/src/ui/item-group/use-item-group.ts

@@ -0,0 +1,51 @@
+/**
+ * External dependencies
+ */
+import { cx } from 'emotion';
+
+/**
+ * Internal dependencies
+ */
+import { useContextSystem } from '../context';
+// eslint-disable-next-line no-duplicate-imports
+import type { PolymorphicComponentProps } from '../context';
+
+/**
+ * Internal dependencies
+ */
+import * as styles from './styles';
+
+export interface Props {
+	bordered?: boolean;
+	rounded?: boolean;
+	separated?: boolean;
+	size?: 'large' | 'medium' | 'small';
+}
+
+export function useItemGroup(
+	props: PolymorphicComponentProps< Props, 'div' >
+) {
+	const {
+		className,
+		bordered = false,
+		rounded = true,
+		separated = false,
+		role = 'list',
+		...otherProps
+	} = useContextSystem( props, 'ItemGroup' );
+
+	const classes = cx(
+		bordered && styles.bordered,
+		( bordered || separated ) && styles.separated,
+		rounded && styles.rounded,
+		className
+	);
+
+	return {
+		bordered,
+		className: classes,
+		role,
+		separated,
+		...otherProps,
+	};
+}

packages/components/src/ui/item-group/use-item.ts

@@ -0,0 +1,50 @@
+/**
+ * External dependencies
+ */
+import { cx } from 'emotion';
+
+/**
+ * Internal dependencies
+ */
+import { useContextSystem } from '../context';
+// eslint-disable-next-line no-duplicate-imports
+import type { PolymorphicComponentProps } from '../context';
+import * as styles from './styles';
+import { useItemGroupContext } from './context';
+
+export interface Props {
+	action?: boolean;
+	size?: 'small' | 'medium' | 'large';
+}
+
+export function useItem( props: PolymorphicComponentProps< Props, 'div' > ) {
+	const {
+		action = false,
+		as: asProp,
+		className,
+		role = 'listitem',
+		size: sizeProp,
+		...otherProps
+	} = useContextSystem( props, 'Item' );
+
+	const { spacedAround, size: contextSize } = useItemGroupContext();
+
+	const size = sizeProp || contextSize;
+
+	const as = asProp || action ? 'button' : 'div';
+
+	const classes = cx(
+		action && styles.unstyledButton,
+		styles.itemSizes[ size ] || styles.itemSizes.medium,
+		styles.item,
+		spacedAround && styles.spacedAround,
+		className
+	);
+
+	return {
+		as,
+		className: classes,
+		role,
+		...otherProps,
+	};
+}

packages/components/src/utils/config-values.js

@@ -5,6 +5,8 @@ import { space } from '../ui/utils/space';
 import { COLORS } from './colors-values';
 
 const CONTROL_HEIGHT = '30px';
+const CONTROL_PADDING_X = '12px';
+
 const CARD_PADDING_X = space( 3 );
 const CARD_PADDING_Y = space( 3 );
 
@@ -34,6 +36,10 @@ export default {
 	fontWeight: 'normal',
 	fontWeightHeading: '600',
 	gridBase: '4px',
+	controlPaddingX: CONTROL_PADDING_X,
+	controlPaddingXLarge: `calc(${ CONTROL_PADDING_X } * 1.3334)`,
+	controlPaddingXSmall: `calc(${ CONTROL_PADDING_X } / 1.3334)`,
+	controlBorderRadius: '2px',
 	controlHeight: CONTROL_HEIGHT,
 	controlHeightLarge: `calc( ${ CONTROL_HEIGHT } * 1.2 )`,
 	controlHeightSmall: `calc( ${ CONTROL_HEIGHT } * 0.8 )`,