@rsmdc/menu-surface NPM

Menu Surface

The MDC Menu Surface component is a reusable surface that appears above the content of the page and can be positioned adjacent to an element. Menu Surfaces require JavaScript to properly position themselves when opening.

Design & API Documentation

Installation

npm install @rsmdc/menu-surface

Usage

HTML Structure

<div class="mdc-menu-surface">
...
</div>

Styles

@import "@rsmdc/menu-surface/mdc-menu-surface";

JavaScript Instantiation

import {MDCMenuSurface} from '@rsmdc/menu-surface';

const menuSurface = new MDCMenuSurface(document.querySelector('.mdc-menu-surface'));

See Importing the JS component for more information on how to import JavaScript.

Variants

Anchors and Positioning

Anchored To Parent

The menu surface can be positioned to automatically anchor to a parent element when opened.

<div id="toolbar" class="toolbar mdc-menu-surface--anchor">
  <div class="mdc-menu-surface">
  ...
  </div>
</div>

Anchor To Element Within Wrapper

The menu surface can be positioned to automatically anchor to another element, by wrapping the other element with the anchor class.

<div class="mdc-menu-surface--anchor">
  <button id="menu-surface-button">Open Menu Surface</button>
  <div class="mdc-menu-surface">
  ...
  </div>
</div>

Fixed Position

The menu surface can use fixed positioning when being displayed.

<div class="mdc-menu-surface mdc-menu-surface--fixed">
...
</div>

Or in JS:

// ...
menuSurface.setFixedPosition(true);

Absolute Position

The menu surface can use absolute positioning when being displayed. This requires that the element containing the menu(body if using hoistMenuToBody()) has the position: relative style.

<div class="mdc-menu-surface">
...
</div>

// ...
menuSurface.hoistMenuToBody(); // Not required if the menu-surface is already positioned on the body.
menuSurface.setAbsolutePosition(100, 100);

Style Customization

CSS Classes

CSS Class	Description
`mdc-menu-surface`	Mandatory.
`mdc-menu-surface--animating-open`	Indicates the menu surface is currently animating open. This class is removed once the animation completes.
`mdc-menu-surface--open`	Indicates the menu surface is currently open, or is currently animating open.
`mdc-menu-surface--animating-closed`	Indicates the menu surface is currently animating closed. This class is removed once the animation completes.
`mdc-menu-surface--anchor`	Used to indicate which element the menu should be anchored to.
`mdc-menu-surface--fixed`	Used to indicate that the menu is using fixed positioning.

Sass Mixins

Mixin	Description
`mdc-menu-surface-ink-color($color)`	Sets the `color` property of the `mdc-menu-surface`.
`mdc-menu-surface-fill-color($color)`	Sets the `background-color` property of the `mdc-menu-surface`.
`mdc-menu-surface-corner-radius($radius)`	Sets the `border-radius` property of the `mdc-menu-surface`.

`MDCMenuSurface` Properties and Methods

Property	Value Type	Description
`open`	Boolean	Proxies to the foundation's `isOpen`/(`open`, `close`) methods.
`quickOpen`	Boolean	Proxies to the foundation's `setQuickOpen()` method.

Method Signature	Description
`setAnchorCorner(Corner) => void`	Proxies to the foundation's `setAnchorCorner(Corner)` method.
`setAnchorMargin(AnchorMargin) => void`	Proxies to the foundation's `setAnchorMargin(AnchorMargin)` method.
`setFixedPosition(isFixed: boolean) => void`	Adds the `mdc-menu-surface--fixed` class to the `mdc-menu-surface` element. Proxies to the foundation's `setIsHoisted()` and `setFixedPosition()` methods.
`setAbsolutePosition(x: number, y: number) => void`	Proxies to the foundation's `setAbsolutePosition(x, y)` method. Used to set the absolute x/y position of the menu on the page. Should only be used when the menu is hoisted to the body.
`setMenuSurfaceAnchorElement(element: Element) => void`	Changes the element used as an anchor for `menu-surface` positioning logic. Should be used with conjunction with `hoistMenuToBody()`.
`hoistMenuToBody() => void`	Removes the `menu-surface` element from the DOM and appends it to the `body` element. Should be used to overcome `overflow: hidden` issues.
`setIsHoisted() => void`	Proxies to the foundation's `setIsHoisted` method.
`getDefaultFoundation() => MDCMenuSurfaceFoundation`	Returns the foundation.

Events

Event Name	Data	Description
`MDCMenuSurface:closed`	none	Event emitted after the menu surface is closed.
`MDCMenuSurface:opened`	none	Event emitted after the menu surface is opened.

Usage Within Frameworks

If you are using a JavaScript framework, such as React or Angular, you can create a Menu Surface for your framework. Depending on your needs, you can use the Simple Approach: Wrapping MDC Web Vanilla Components, or the Advanced Approach: Using Foundations and Adapters. Please follow the instructions here.

`MDCMenuSurfaceAdapter`

Method Signature	Description
`addClass(className: string) => void`	Adds a class to the root element.
`removeClass(className: string) => void`	Removes a class from the root element.
`hasClass(className: string) => boolean`	Returns a boolean indicating whether the root element has a given class.
`hasAnchor: () => boolean`	Returns whether the menu surface has an anchor for positioning.
`notifyClose() => void`	Dispatches an event notifying listeners that the menu surface has been closed.
`notifyOpen() => void`	Dispatches an event notifying listeners that the menu surface has been opened.
`isElementInContainer(el: Element) => Boolean`	Returns true if the `el` Element is inside the `mdc-menu-surface` container.
`isRtl() => boolean`	Returns boolean indicating whether the current environment is RTL.
`setTransformOrigin(value: string) => void`	Sets the transform origin for the menu surface element.
`isFocused() => boolean`	Returns a boolean value indicating whether the root element of the menu surface is focused.
`saveFocus() => void`	Stores the currently focused element on the document, for restoring with `restoreFocus`.
`restoreFocus() => void`	Restores the previously saved focus state, by making the previously focused element the active focus again.
`isFirstElementFocused() => boolean`	Returns a boolean value indicating if the first focusable element of the menu-surface is focused.
`isLastElementFocused() => boolean`	Returns a boolean value indicating if the last focusable element of the menu-surface is focused.
`focusFirstElement() => void`	Focuses the first focusable element of the menu-surface.
`focusLastElement() => void`	Focuses the last focusable element of the menu-surface.
`getInnerDimensions() => {width: number, height: number}`	Returns an object with the items container width and height.
`getAnchorDimensions() => {width: number, height: number, top: number, right: number, bottom: number, left: number}`	Returns an object with the dimensions and position of the anchor (same semantics as `DOMRect`).
`getBodyDimensions() => {width: number, height: number}`	Returns an object with width and height of the body, in pixels.
`getWindowDimensions() => {width: number, height: number}`	Returns an object with width and height of the viewport, in pixels.
`getWindowScroll() => {x: number, y: number}`	Returns an object with the amount the body has been scrolled on the `x` and `y` axis.
`setPosition(position: {top: string, right: string, bottom: string, left: string}) => void`	Sets the position of the menu surface element.
`setMaxHeight(value: string) => void`	Sets `max-height` style for the menu surface element.

`MDCMenuSurfaceFoundation`

Method Signature	Description
`setAnchorCorner(corder: Corner) => void`	Sets the corner that the menu surface will be anchored to. See constants.js
`setAnchorMargin(margin: AnchorMargin) => void`	Sets the distance from the anchor point that the menu surface should be shown.
`setIsHoisted(isHoisted: boolean) => void`	Sets whether the menu surface has been hoisted to the body so that the offsets are calculated relative to the page and not the anchor.
`setFixedPosition(isFixed: boolean) => void`	Sets whether the menu surface is using fixed positioning.
`setAbsolutePosition(x: number, y: numnber) => void`	Sets the absolute x/y position of the menu. Should only be used when the menu is hoisted or using fixed positioning.
`handleBodyClick(event: Event) => void`	Method used as the callback function for the `click` event.
`handleKeydown(event: Event) => void`	Method used as the callback function for the `keydown` events.
`open() => void`	Opens the menu surface.
`close() => void`	Closes the menu.
`isOpen() => boolean`	Returns a boolean indicating whether the menu surface is open.
`setQuickOpen(quickOpen: boolean) => void`	Sets whether the menu surface should open and close without animation when the `open`/`close` methods are called.