The issue is I want to make NVDA read some message after pressing a button. For example, there is a button "add new row" which adds new row to a grid. User who uses NVDA screen reader presses Enter on the button and then I want to notify him about the successful result (row has been added). Another example I have a form where user makes some changes. "Save" button is available on the form - after preesing I want to notify the user "changes has been saved". Is there any way to do this without throwing a toaster message? I want to add that in my case after pressing the buttons, focus stays on them.
2 Answers
You are looking for the aria-live
attribute
This allows you to provide updates to a screen reader user by changing the text inside the container that has aria-live
on it.
For your use case you want to use aria-live="polite"
, aria-live="assertive"
should only be used for time sensitive information such as alerts for being logged out etc.
An aria-live
region that is not visible
You do not have to have a visible aria-live
region, but it must be accessible by a screen reader.
For that we can make it visually hidden using my visually hidden class (which is better than sr-only
and is future proofed as clip
has been deprecated)
.visually-hidden {
border: 0;
padding: 0;
margin: 0;
position: absolute !important;
height: 1px;
width: 1px;
overflow: hidden;
clip: rect(1px 1px 1px 1px); /* IE6, IE7 - a 0 height clip, off to the bottom right of the visible 1px box */
clip: rect(1px, 1px, 1px, 1px); /*maybe deprecated but we need to support legacy browsers */
clip-path: inset(50%); /*modern browsers, clip-path works inwards from each corner*/
white-space: nowrap; /* added line to stop words getting smushed together (as they go onto seperate lines and some screen readers do not understand line feeds as a space */
}
<div class="visually-hidden" aria-live="polite">
Whatever you put in here via JavaScript will get read out to screen readers as an appropraite quiet time. This is not visible.
</div>
<p>This is visible</p>
Example from MDN
As link only answers are never good I have included the example from the linked article on MDN.
const PLANETS_INFO = {
mercury: {
title: 'Mercury',
description: 'Mercury is the smallest and innermost planet in the Solar System. It is named after the Roman deity Mercury, the messenger to the gods.'
},
venus: {
title: "Venus",
description: 'Venus is the second planet from the Sun. It is named after the Roman goddess of love and beauty.'
},
earth: {
title: "Earth",
description: 'Earth is the third planet from the Sun and the only object in the Universe known to harbor life.'
},
mars: {
title: "Mars",
description: 'Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury. In English, Mars carries a name of the Roman god of war, and is often referred to as the "Red Planet".'
}
};
function renderPlanetInfo(planet) {
const planetTitle = document.querySelector('#planetTitle');
const planetDescription = document.querySelector('#planetDescription');
if (planet in PLANETS_INFO) {
planetTitle.textContent = PLANETS_INFO[planet].title;
planetDescription.textContent = PLANETS_INFO[planet].description;
} else {
planetTitle.textContent = 'No planet selected';
planetDescription.textContent = 'Select a planet to view its description';
}
}
const renderPlanetInfoButton = document.querySelector('#renderPlanetInfoButton');
renderPlanetInfoButton.addEventListener('click', event => {
const planetsSelect = document.querySelector('#planetsSelect');
const selectedPlanet = planetsSelect.options[planetsSelect.selectedIndex].value;
renderPlanetInfo(selectedPlanet);
});
<fieldset>
<legend>Planet information</legend>
<label for="planetsSelect">Planet:</label>
<select id="planetsSelect" aria-controls="planetInfo">
<option value="">Select a planet…</option>
<option value="mercury">Mercury</option>
<option value="venus">Venus</option>
<option value="earth">Earth</option>
<option value="mars">Mars</option>
</select>
<button id="renderPlanetInfoButton">Go</button>
</fieldset>
<div role="region" id="planetInfo" aria-live="polite">
<h2 id="planetTitle">No planet selected</h2>
<p id="planetDescription">Select a planet to view its description</p>
</div>
<p><small>Information courtesy <a href="https://en.wikipedia.org/wiki/Solar_System#Inner_Solar_System">Wikipedia</a></small></p>
Screen reader only text is recommended for information that's apparent visually but not available for non sighted users. I suggest that you try using clip + clip-path method as progressive enhancements to support both older and newer browser versions.
.screenreader-text {
border: 0;
/*Clipping defines what part of an element should be displayed*/
/* Deprecated clip property for older browsers */
clip: rect(1px, 1px, 1px, 1px);
/* clip-path for newer browsers. inset(50%) defines an inset rectangle that makes the content disappear */
clip-path: inset(50%);
height: 1px;
margin: -1px;
overflow: hidden;
padding: 0;
position: absolute !important;
width: 1px;
word-wrap: normal !important;
}