Pinafore-Web-Client-Frontend/routes/_utils/delegate.js

50 lines
1.2 KiB
JavaScript

// Delegate certain events to the global document for perf purposes.
import { mark, stop } from './marks'
const callbacks = {}
if (process.browser && process.env.NODE_ENV !== 'production') {
window.delegateCallbacks = callbacks
}
function onEvent (e) {
let { type, keyCode, target } = e
if (!(type === 'click' || (type === 'keydown' && keyCode === 13))) {
// we're not interested in any non-click or non-Enter events
return
}
mark('delegate onEvent')
let key
let element = target
while (element) {
if ((key = element.getAttribute('delegate-key'))) {
break
}
element = element.parentElement
}
if (key && callbacks[key]) {
callbacks[key](e)
}
stop('delegate onEvent')
}
export function registerClickDelegates (component, delegates) {
Object.assign(callbacks, delegates)
component.on('destroy', () => {
Object.keys(delegates).forEach(key => {
delete callbacks[key]
})
})
}
export function registerClickDelegate (component, key, callback) {
registerClickDelegates(component, {[key]: callback})
}
if (process.browser) {
document.addEventListener('click', onEvent)
document.addEventListener('keydown', onEvent)
}