lib/js/src/offcanvas.js

/**
 * --------------------------------------------------------------------------
 * Bootstrap (v5.1.3): offcanvas.js
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
 * --------------------------------------------------------------------------
 */

import {
    defineJQueryPlugin,
    getElementFromSelector,
    isDisabled,
    isVisible,
    typeCheckConfig
} from './util/index'
import ScrollBarHelper from './util/scrollbar'
import EventHandler from './dom/event-handler'
import BaseComponent from './base-component'
import SelectorEngine from './dom/selector-engine'
import Manipulator from './dom/manipulator'
import Backdrop from './util/backdrop'
import FocusTrap from './util/focustrap'
import {
    enableDismissTrigger
} from './util/component-functions'

/**
 * ------------------------------------------------------------------------
 * Constants
 * ------------------------------------------------------------------------
 */

const NAME = 'offcanvas'
const DATA_KEY = 'bs.offcanvas'
const EVENT_KEY = `.${DATA_KEY}`
const DATA_API_KEY = '.data-api'
const EVENT_LOAD_DATA_API = `load${EVENT_KEY}${DATA_API_KEY}`
const ESCAPE_KEY = 'Escape'

const Default = {
    backdrop: true,
    keyboard: true,
    scroll: false
}

const DefaultType = {
    backdrop: 'boolean',
    keyboard: 'boolean',
    scroll: 'boolean'
}

const CLASS_NAME_SHOW = 'show'
const CLASS_NAME_BACKDROP = 'offcanvas-backdrop'
const OPEN_SELECTOR = '.offcanvas.show'

const EVENT_SHOW = `show${EVENT_KEY}`
const EVENT_SHOWN = `shown${EVENT_KEY}`
const EVENT_HIDE = `hide${EVENT_KEY}`
const EVENT_HIDDEN = `hidden${EVENT_KEY}`
const EVENT_CLICK_DATA_API = `click${EVENT_KEY}${DATA_API_KEY}`
const EVENT_KEYDOWN_DISMISS = `keydown.dismiss${EVENT_KEY}`

const SELECTOR_DATA_TOGGLE = '[data-bs-toggle="offcanvas"]'

/**
 * ------------------------------------------------------------------------
 * Class Definition
 * ------------------------------------------------------------------------
 */

class Offcanvas extends BaseComponent {
    constructor(element, config) {
        super(element)

        this._config = this._getConfig(config)
        this._isShown = false
        this._backdrop = this._initializeBackDrop()
        this._focustrap = this._initializeFocusTrap()
        this._addEventListeners()
    }

    // Getters

    static get NAME() {
        return NAME
    }

    static get Default() {
        return Default
    }

    // Public

    toggle(relatedTarget) {
        return this._isShown ? this.hide() : this.show(relatedTarget)
    }

    show(relatedTarget) {
        if (this._isShown) {
            return
        }

        const showEvent = EventHandler.trigger(this._element, EVENT_SHOW, {
            relatedTarget
        })

        if (showEvent.defaultPrevented) {
            return
        }

        this._isShown = true
        this._element.style.visibility = 'visible'

        this._backdrop.show()

        if (!this._config.scroll) {
            new ScrollBarHelper().hide()
        }

        this._element.removeAttribute('aria-hidden')
        this._element.setAttribute('aria-modal', true)
        this._element.setAttribute('role', 'dialog')
        this._element.classList.add(CLASS_NAME_SHOW)

        const completeCallBack = () => {
            if (!this._config.scroll) {
                this._focustrap.activate()
            }

            EventHandler.trigger(this._element, EVENT_SHOWN, {
                relatedTarget
            })
        }

        this._queueCallback(completeCallBack, this._element, true)
    }

    hide() {
        if (!this._isShown) {
            return
        }

        const hideEvent = EventHandler.trigger(this._element, EVENT_HIDE)

        if (hideEvent.defaultPrevented) {
            return
        }

        this._focustrap.deactivate()
        this._element.blur()
        this._isShown = false
        this._element.classList.remove(CLASS_NAME_SHOW)
        this._backdrop.hide()

        const completeCallback = () => {
            this._element.setAttribute('aria-hidden', true)
            this._element.removeAttribute('aria-modal')
            this._element.removeAttribute('role')
            this._element.style.visibility = 'hidden'

            if (!this._config.scroll) {
                new ScrollBarHelper().reset()
            }

            EventHandler.trigger(this._element, EVENT_HIDDEN)
        }

        this._queueCallback(completeCallback, this._element, true)
    }

    dispose() {
        this._backdrop.dispose()
        this._focustrap.deactivate()
        super.dispose()
    }

    // Private

    _getConfig(config) {
        config = {
            ...Default,
            ...Manipulator.getDataAttributes(this._element),
            ...(typeof config === 'object' ? config : {})
        }
        typeCheckConfig(NAME, config, DefaultType)
        return config
    }

    _initializeBackDrop() {
        return new Backdrop({
            className: CLASS_NAME_BACKDROP,
            isVisible: this._config.backdrop,
            isAnimated: true,
            rootElement: this._element.parentNode,
            clickCallback: () => this.hide()
        })
    }

    _initializeFocusTrap() {
        return new FocusTrap({
            trapElement: this._element
        })
    }

    _addEventListeners() {
        EventHandler.on(this._element, EVENT_KEYDOWN_DISMISS, event => {
            if (this._config.keyboard && event.key === ESCAPE_KEY) {
                this.hide()
            }
        })
    }

    // Static

    static jQueryInterface(config) {
        return this.each(function() {
            const data = Offcanvas.getOrCreateInstance(this, config)

            if (typeof config !== 'string') {
                return
            }

            if (data[config] === undefined || config.startsWith('_') || config === 'constructor') {
                throw new TypeError(`No method named "${config}"`)
            }

            data[config](this)
        })
    }
}

/**
 * ------------------------------------------------------------------------
 * Data Api implementation
 * ------------------------------------------------------------------------
 */

EventHandler.on(document, EVENT_CLICK_DATA_API, SELECTOR_DATA_TOGGLE, function(event) {
    const target = getElementFromSelector(this)

    if (['A', 'AREA'].includes(this.tagName)) {
        event.preventDefault()
    }

    if (isDisabled(this)) {
        return
    }

    EventHandler.one(target, EVENT_HIDDEN, () => {
        // focus on trigger when it is closed
        if (isVisible(this)) {
            this.focus()
        }
    })

    // avoid conflict when clicking a toggler of an offcanvas, while another is open
    const allReadyOpen = SelectorEngine.findOne(OPEN_SELECTOR)
    if (allReadyOpen && allReadyOpen !== target) {
        Offcanvas.getInstance(allReadyOpen).hide()
    }

    const data = Offcanvas.getOrCreateInstance(target)
    data.toggle(this)
})

EventHandler.on(window, EVENT_LOAD_DATA_API, () =>
    SelectorEngine.find(OPEN_SELECTOR).forEach(el => Offcanvas.getOrCreateInstance(el).show())
)

enableDismissTrigger(Offcanvas)
/**
 * ------------------------------------------------------------------------
 * jQuery
 * ------------------------------------------------------------------------
 */

defineJQueryPlugin(Offcanvas)

export default Offcanvas