handle

Handle events on elements

Installation

npm install handle

API

handle(element, event, fn [, capture])

Handle event on element using fn. It returns a function that can be called to stop listening. e.g. to build once you could write:

var handle = require('handle');

function once(element, event, fn, capture) {
  var dispose = handle(element, event, function (el, event) {
    dispose();
    fn(el, event);
  }, capture);
}

Typical usage might look like:

var handle = require('handle');

handle(document.getElementById('my-button'), 'click', function (button, e) {
  e.preventDefault();
  // do something
});

handle(elements, event, fn [, capture])

You can handle the same event on a whole list of elements in one go. This does not need to be an array, it just needs to have a .length property that is a number and have indexed values. e.g.

var handle = require('handle');

handle(document.querySelector('[data-action="do-something"]'), 'click', function (button, e) {
  e.preventDefault();
  // do something
});

It too returns a dispose funciton.

handle(selector, event, fn [, capture])

This works just like jQuery's $(document.body).delecate(selector, event, function (e) { fn(this, e) }). It too returns a dispose function.

The advantages/disadvantages of using this method are:

• It will still capture the event if the element matching selector is added to the DOM after handle is called.
• It captures the event later (i.e. after those handlers that were attached directly to elements lower in the DOM chain)
• It only binds to one element, so can have better performance, but it must check every event for a match, so can have worse performance

e.g.

var handle = require('handle');

handle('[data-action="do-something"]', 'click', function (button, e) {
  e.preventDefault();
  // do something
});

If you want to delegate from something other than document.body you can select a start element via the .on method:

var handle = require('handle').on(document.getElementById('hideable-list'));

handle('li', 'click', function (li, e) {
  e.preventDefault();
  li.style.visibility = 'hidden';
});

handle.once(element|elements|selector, event [, capture])

Return a promise that is resolved with the event args once the event is fired. e.preventDefault() is also called since it must be called within the same turn to work.

Running Tests

Tests can be easilly run locally in the browser of your choice, and have passed if it ends with # ok. They are also run on testling-ci when pushed to the repository:

npm install
npm test

License

MIT