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Time Input Polyfill

JS Deliver hits per month

An accessible polyfill for <input type='time'/> elements.

  • ✔️ Modeled after the Chrome 78 and Firefox 70 desktop implementations.
  • ✔️ Fully keyboard and screen reader accessible.
  • ✔️ Submits the same values to servers as real time inputs (24 hour time).
  • ✔️ Only downloads the full polyfill code in the browsers that need it.
  • ✔️ Zero dependencies.

Demo available here: https://dan503.github.io/time-input-polyfill/

The recommended version is 1.0.11 or higher.

If the recommended version in this documentation is out of sync with the npm version, this is because npm only allows readme edits to be committed through full releases. To prevent needless cache invalidation, I'll only update the recommended version number when there are actual changes to the polyfill code. The current recommended version is 1.0.11. As long as you are using a version that is equal to or higher than that, you are using the latest version of the polyfill.

Pre-built components

To make it easier to implement this polyfill into your projects, I have some pre-built component versions of it that you might find easier to use.

Fastest and easiest way to implement

Add the following script element to your page:

<script src="https://cdn.jsdelivr.net/npm/time-input-polyfill"></script>

Alternatively you can download it via npm and use it through commonJS or an ES6 import statement.

npm i time-input-polyfill

Then require it in your main JavaScript file like so:

// ES5
require('time-input-polyfill/auto')

// ES6
import 'time-input-polyfill/auto'

That's all you need to do.

What did I just do?

You didn't load the actual polyfill onto the page, you loaded a much smaller automatic initialiser function instead.

  1. The initialiser checks if the browser supports input[type="time"] elements.
  2. If it does, it skips the rest of the functionality.
  3. If it does not, it will:
    1. load https://cdn.jsdelivr.net/npm/[email protected]/dist/time-input-polyfill.min.js (the actual polyfill).
    2. Collect all existing input[type="time"] elements on the page.
    3. Loop through each input[type="time"] element and apply the polyfill to it.

I need more control

The following downloads the full polyfill in all browsers, take a look at the auto.mjs file if you want to see how it loads the polyfill dynamically.

npm

First check for input[type="time"] support.

import supportsTime from 'time-input-polyfill/supportsTime'

if (!supportsTime) {
	//Apply polyfill here
}

Then gather a list of all input[type="time"] elements on the page, and loop through them to apply the polyfill.

import supportsTime from 'time-input-polyfill/supportsTime'
import TimePolyfill from 'time-input-polyfill'

if (!supportsTime) {
	// Converting to an array for IE support
	const $$inputs = [].slice.call(
		document.querySelectorAll('input[type="time"]')
	)
	$$inputs.forEach(function ($input) {
		new TimePolyfill($input)
	})
}

TimePolyfill in this case will be a function that is only accessible from the file that it was required in.

CDN

First check for input[type="time"] support.

<script src="https://cdn.jsdelivr.net/npm/[email protected]/core/helpers/supportsTime.js"></script>
if (!supportsTime) {
	//Apply polyfill here
}

Then gather a list of all input[type="time"] elements on the page, and loop through them to apply the polyfill.

<script src="https://cdn.jsdelivr.net/npm/[email protected]/core/helpers/supportsTime.js"></script>
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/time-input-polyfill.min.js"></script>
if (!supportsTime) {
	// Converting to an array for IE support
	const $$inputs = [].slice.call(
		document.querySelectorAll('input[type="time"]')
	)
	$$inputs.forEach(function ($input) {
		new TimePolyfill($input)
	})
}

This will add a global TimePolyfill function to the page.

Shadow DOM

When your code is inside a component that resides in the Shadow DOM, the polyfill will not be able to find your label element. For this case, you can pass your label element in directly.

<label id="myLabel" for="timeInput">Label text</label>
<input type="time" id="timeInput" />
import timePolyfill from 'time-input-polyfill'

// The following element must not be in a shadow DOM
const componentRootElem = document.getElementById(
	'idOfYourShadowDomComponentRootElement'
)

const timeLabelElem = componentRootElem.shadowRoot.getElementById('myLabel')
const timeInputElem = componentRootElem.shadowRoot.getElementById('timeInput')
timePolyFill(timeInputElem, timeLabelElem)

Major limitations

Note that I refer to an input[type="time"] element that has had the polyfill initialized on it as an $input in this section.

The value of the polyfill will be different to the value of the real input

In browsers that support the time input natively, they will provide the value of the input in 24 hour time (eg. 20:45). The polyfill will provide the value in 12 hour time (08:45 PM). If the polyfill detects that a form is being submitted, the polyfill will quickly switch to 24 hour time in an attempt to align with standard time input functionality.

If this isn't working for you, you can prevent the auto-swap functionality by setting $input.polyfill.autoSwap = false. You can access the current input value in 24 hour time format by reading the data-value attribute.

You can also switch the $input manually to 24 hour time using $input.polyfill.swap(). The polyfill does not function properly at the moment while running in 24 hour time. 24 hour time is only meant to be used as a means of submitting correct values to forms. It is not intended to be used as a permanent mode.

You must call $input.polyfill.update() on dynamic inputs

I couldn't find any reliable way to track when a user uses $input.value = '13:30'. So instead of tracking the use of $input.value, I have attached a .polyfill.update() method to the $input element.

Any time you update the value of the time input element through JavaScript, check that $input.polyfill exists, and if it does, call $input.polyfill.update().

<input id="example" type="time" />
const $input = document.getElementByID('example')
$input.value = '13:30'
// call the update() method whenever the value is updated through JS
if ($input.polyfill) $input.polyfill.update()

The update() method will return the input element that it was called on so it can be chained if you want.

All $input elements must have a label

The polyfill will fail if the $input is missing a label.

The following is a list of ways you can add a label to the $input. The list is in order from the best method to the worst method:

  1. Using the for attribute 
    <label for="uniqueID">Label text</label> <input type="time" id="uniqueID" />
  2. Using the aria-labelledby attribute 
    <p id="uniqueID">Label text</p>
<input type="time" aria-labelledby="uniqueID" />
  3. Nesting the $input inside a <label> (Doesn't require IDs to work but not supported by all screen readers) 
    <label>
	<span>Label text</span>
	<input type="time" />
</label>
  4. Using the title attribute 
    <input type="time" title="Label text" />
  5. Using the aria-label attribute 
    <input type="time" aria-label="Label text" />

Change log

You can view the Change Log on the GitHub Releases page.

Contributing

Please make pull requests against Develop branch rather than Master.

For testing you will need Gulp cli installed (npm i gulp-cli -g) then run gulp --open from a command line interface.