waitUntil for normal Events
npm install event-wait-until
Prevent an event from continuing to propagate up (or down) the down until a Promise has resolved. This is good if you need to do some asynchronous activity before determining if the event should be stopped or prevented.
This is a ponyfill for this WICG issue.
With yarn:
``shell`
yarn add event-wait-until
Here's a simple, and silly, example where we query a Web Worker to determine if the event should be prevented.
`js
anchor.addEventListener('click', ev => {
eventWaitUntil(ev)(new Promise(resolve => {
worker.postMessage({question: 'Should this be prevented?'});
worker.onmessage = function(msg){
const reply = msg.data.reply;
if(reply === 'prevent') {
ev.preventDefault();
}
resolve();
};
}));
});
`
event-wait-until is a function that is placed on the window object as eventWaitUntil. The signature is eventWaitUntil(event) -> fn(promise)`. See the above example.
BSD 2 Clause