fix(radio-group): improve error text accessibility

This commit is contained in:
Maria Hutt
2025-11-03 11:57:28 -08:00
parent f5088213f1
commit cde3f14c2a
3 changed files with 263 additions and 11 deletions

View File

@@ -1,5 +1,6 @@
import type { ComponentInterface, EventEmitter } from '@stencil/core';
import { Component, Element, Event, Host, Listen, Method, Prop, Watch, h } from '@stencil/core';
import { Build, Component, Element, Event, Host, Listen, Method, Prop, State, Watch, h } from '@stencil/core';
import { checkInvalidState } from '@utils/forms';
import { renderHiddenInput } from '@utils/helpers';
import { getIonMode } from '../../global/ionic-global';
@@ -19,9 +20,17 @@ export class RadioGroup implements ComponentInterface {
private errorTextId = `${this.inputId}-error-text`;
private labelId = `${this.inputId}-lbl`;
private label?: HTMLIonLabelElement | null;
private validationObserver?: MutationObserver;
@Element() el!: HTMLElement;
/**
* Track validation state for proper aria-live announcements.
*/
@State() isInvalid = false;
@State() private hintTextID?: string;
/**
* If `true`, the radios can be deselected.
*/
@@ -121,6 +130,53 @@ export class RadioGroup implements ComponentInterface {
this.labelId = label.id = this.name + '-lbl';
}
}
// Watch for class changes to update validation state.
if (Build.isBrowser && typeof MutationObserver !== 'undefined') {
this.validationObserver = new MutationObserver(() => {
const newIsInvalid = checkInvalidState(this.el);
if (this.isInvalid !== newIsInvalid) {
this.isInvalid = newIsInvalid;
/**
* Screen readers tend to announce changes
* to `aria-describedby` when the attribute
* is changed during a blur event for a
* native form control.
* However, the announcement can be spotty
* when using a non-native form control
* and `forceUpdate()`.
* This is due to `forceUpdate()` internally
* rescheduling the DOM update to a lower
* priority queue regardless if it's called
* inside a Promise or not, thus causing
* the screen reader to potentially miss the
* change.
* By using a State variable inside a Promise,
* it guarantees a re-render immediately at
* a higher priority.
*/
Promise.resolve().then(() => {
this.hintTextID = this.getHintTextID();
});
}
});
this.validationObserver.observe(this.el, {
attributes: true,
attributeFilter: ['class'],
});
}
// Always set initial state
this.isInvalid = checkInvalidState(this.el);
}
disconnectedCallback() {
// Clean up validation observer to prevent memory leaks.
if (this.validationObserver) {
this.validationObserver.disconnect();
this.validationObserver = undefined;
}
}
private getRadios(): HTMLIonRadioElement[] {
@@ -244,7 +300,7 @@ export class RadioGroup implements ComponentInterface {
* Renders the helper text or error text values
*/
private renderHintText() {
const { helperText, errorText, helperTextId, errorTextId } = this;
const { helperText, errorText, helperTextId, errorTextId, isInvalid } = this;
const hasHintText = !!helperText || !!errorText;
if (!hasHintText) {
@@ -253,20 +309,20 @@ export class RadioGroup implements ComponentInterface {
return (
<div class="radio-group-top">
<div id={helperTextId} class="helper-text">
{helperText}
<div id={helperTextId} class="helper-text" aria-live="polite">
{!isInvalid ? helperText : null}
</div>
<div id={errorTextId} class="error-text">
{errorText}
<div id={errorTextId} class="error-text" role="alert">
{isInvalid ? errorText : null}
</div>
</div>
);
}
private getHintTextID(): string | undefined {
const { el, helperText, errorText, helperTextId, errorTextId } = this;
const { helperText, errorText, helperTextId, errorTextId, isInvalid } = this;
if (el.classList.contains('ion-touched') && el.classList.contains('ion-invalid') && errorText) {
if (isInvalid && errorText) {
return errorTextId;
}
@@ -287,8 +343,8 @@ export class RadioGroup implements ComponentInterface {
<Host
role="radiogroup"
aria-labelledby={label ? labelId : null}
aria-describedby={this.getHintTextID()}
aria-invalid={this.getHintTextID() === this.errorTextId}
aria-describedby={this.hintTextID}
aria-invalid={this.isInvalid ? 'true' : undefined}
onClick={this.onClick}
class={mode}
>

View File

@@ -0,0 +1,195 @@
<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="UTF-8" />
<title>Radrio Group - Validation</title>
<meta
name="viewport"
content="viewport-fit=cover, width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no"
/>
<link href="../../../../../css/ionic.bundle.css" rel="stylesheet" />
<link href="../../../../../scripts/testing/styles.css" rel="stylesheet" />
<script src="../../../../../scripts/testing/scripts.js"></script>
<script nomodule src="../../../../../dist/ionic/ionic.js"></script>
<script type="module" src="../../../../../dist/ionic/ionic.esm.js"></script>
<style>
.grid {
display: grid;
grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
grid-row-gap: 30px;
grid-column-gap: 30px;
}
h2 {
font-size: 12px;
font-weight: normal;
color: var(--ion-color-step-600);
margin-top: 10px;
margin-bottom: 5px;
}
.validation-info {
margin: 20px;
padding: 10px;
background: var(--ion-color-light);
border-radius: 4px;
}
</style>
</head>
<body>
<ion-app>
<ion-header>
<ion-toolbar>
<ion-title>Radio Group - Validation Test</ion-title>
</ion-toolbar>
</ion-header>
<ion-content class="ion-padding">
<div class="validation-info">
<h2>Screen Reader Testing Instructions:</h2>
<ol>
<li>Enable your screen reader (VoiceOver, NVDA, JAWS, etc.)</li>
<li>Tab through the form fields</li>
<li>When you tab away from an empty required field, the error should be announced immediately</li>
<li>The error text should be announced BEFORE the next field is announced</li>
<li>Test in Chrome, Safari, and Firefox to verify consistent behavior</li>
</ol>
</div>
<div class="grid">
<div>
<h2>Required Field</h2>
<ion-radio-group
id="fruits-radio-group"
helper-text="You must select one to continue"
error-text="Please select a fruit"
allow-empty-selection="true"
required
>
<ion-radio value="grapes">Grapes</ion-radio><br />
<ion-radio value="strawberries">Strawberries</ion-radio>
</ion-radio-group>
</div>
<div>
<h2>Optional Field (No Validation)</h2>
<ion-radio-group
id="optional-radio-group"
helper-text="You can skip this field"
allow-empty-selection="true"
required
>
<ion-radio value="cucumbers">Cucumbers</ion-radio><br />
<ion-radio value="tomatoes">Tomatoes</ion-radio>
</ion-radio-group>
</div>
</div>
<div class="ion-padding">
<ion-button id="submit-btn" expand="block" disabled>Submit Form</ion-button>
<ion-button id="reset-btn" expand="block" fill="outline">Reset Form</ion-button>
</div>
</ion-content>
</ion-app>
<script>
// Simple validation logic
const radioGroups = document.querySelectorAll('ion-radio-group');
const submitBtn = document.getElementById('submit-btn');
const resetBtn = document.getElementById('reset-btn');
// Track which fields have been touched
const touchedFields = new Set();
// Validation functions
const validators = {
'fruits-radio-group': (value) => {
return value !== undefined;
},
'optional-checkbox': () => true, // Always valid
};
function validateField(radioGroup) {
const radioGroupId = radioGroup.id;
const value = radioGroup.value;
const isValid = validators[radioGroupId] ? validators[radioGroupId](value) : true;
// Only show validation state if field has been touched
if (touchedFields.has(radioGroupId)) {
if (isValid) {
radioGroup.classList.remove('ion-invalid');
radioGroup.classList.add('ion-valid');
} else {
radioGroup.classList.remove('ion-valid');
radioGroup.classList.add('ion-invalid');
}
radioGroup.classList.add('ion-touched');
}
return isValid;
}
function validateForm() {
let allValid = true;
radioGroups.forEach((radioGroup) => {
if (radioGroup.id !== 'optional-radio-group') {
const isValid = validateField(radioGroup);
if (!isValid) {
allValid = false;
}
}
});
submitBtn.disabled = !allValid;
return allValid;
}
// Add event listeners
radioGroups.forEach((radioGroup) => {
// Mark as touched on blur
radioGroup.addEventListener('ionBlur', (e) => {
console.log('Blur event on:', radioGroup.id);
touchedFields.add(radioGroup.id);
validateField(radioGroup);
validateForm();
const isInvalid = radioGroup.classList.contains('ion-invalid');
if (isInvalid) {
console.log('Field marked invalid:', radioGroup.label, radioGroup.errorText);
}
});
// Validate on change
radioGroup.addEventListener('ionChange', (e) => {
console.log('Change event on:', radioGroup.id);
if (touchedFields.has(radioGroup.id)) {
validateField(radioGroup);
validateForm();
}
});
});
// Reset button
resetBtn.addEventListener('click', () => {
radioGroups.forEach((radioGroup) => {
radioGroup.value = '';
radioGroup.classList.remove('ion-valid', 'ion-invalid', 'ion-touched');
});
touchedFields.clear();
submitBtn.disabled = true;
});
// Submit button
submitBtn.addEventListener('click', () => {
if (validateForm()) {
alert('Form submitted successfully!');
}
});
// Initial setup
validateForm();
</script>
</body>
</html>

View File

@@ -3,7 +3,8 @@ type FormElement =
| HTMLIonTextareaElement
| HTMLIonSelectElement
| HTMLIonCheckboxElement
| HTMLIonToggleElement;
| HTMLIonToggleElement
| HTMLElement;
/**
* Checks if the form element is in an invalid state based on