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.