fix(input): announce helper and error text in screen readers

Author: thetaPC

core/src/components/input/input.tsx

@@ -575,7 +575,28 @@ export class Input implements ComponentInterface {
   private renderHintText() {
     const { helperText, errorText } = this;
 
-    return [<div class="helper-text">{helperText}</div>, <div class="error-text">{errorText}</div>];
+    return [
+      <div id={HELPER_TEXT_ID} class="helper-text">
+        {helperText}
+      </div>,
+      <div id={ERROR_TEXT_ID} class="error-text">
+        {errorText}
+      </div>,
+    ];
+  }
+
+  private getHintTextID(): string | undefined {
+    const { el, helperText, errorText } = this;
+
+    if (el.classList.contains('ion-touched') && el.classList.contains('ion-invalid') && errorText) {
+      return ERROR_TEXT_ID;
+    }
+
+    if (helperText) {
+      return HELPER_TEXT_ID;
+    }
+
+    return undefined;
   }
 
   private renderCounter() {
@@ -700,6 +721,8 @@ export class Input implements ComponentInterface {
     const hasValue = this.hasValue();
     const hasStartEndSlots = el.querySelector('[slot="start"], [slot="end"]') !== null;
 
+    console.log('el', this.el);
+    console.log('id', this.getHintTextID());
     /**
      * If the label is stacked, it should always sit above the input.
      * For floating labels, the label should move above the input if
@@ -777,6 +800,8 @@ export class Input implements ComponentInterface {
               onKeyDown={this.onKeydown}
               onCompositionstart={this.onCompositionStart}
               onCompositionend={this.onCompositionEnd}
+              aria-describedby={this.getHintTextID()}
+              aria-invalid={this.getHintTextID() === ERROR_TEXT_ID}
               {...this.inheritedAttributes}
             />
             {this.clearInput && !readonly && !disabled && (
@@ -817,3 +842,5 @@ export class Input implements ComponentInterface {
 }
 
 let inputIds = 0;
+const HELPER_TEXT_ID = `${'helper-text-' + inputIds}`;
+const ERROR_TEXT_ID = `${'error-text-' + inputIds}`;

core/src/components/input/test/bottom-content/index.html

@@ -49,67 +49,40 @@
       </ion-header>
 
       <ion-content id="content" class="ion-padding">
-        <div class="grid">
-          <div class="grid-item">
-            <h2>No Hint</h2>
-            <ion-input label="Email"></ion-input>
-          </div>
+        <ion-input
+          type="email"
+          fill="solid"
+          label="Email"
+          label-placement="floating"
+          helper-text="Enter a valid email"
+          error-text="Invalid email"
+        ></ion-input>
 
-          <div class="grid-item">
-            <h2>Helper Hint</h2>
-            <ion-input label="Email" helper-text="Enter your email"></ion-input>
-          </div>
+        <script>
+          const input = document.querySelector('ion-input');
 
-          <div class="grid-item">
-            <h2>Error Hint</h2>
-            <ion-input
-              class="ion-touched ion-invalid"
-              label="Email"
-              error-text="Please enter a valid email"
-            ></ion-input>
-          </div>
+          input.addEventListener('ionInput', (ev) => validate(ev));
+          input.addEventListener('ionBlur', () => markTouched());
 
-          <div class="grid-item">
-            <h2>Custom Error Color</h2>
-            <ion-input
-              class="ion-touched ion-invalid custom-error-color"
-              label="Email"
-              error-text="Please enter a valid email"
-            ></ion-input>
-          </div>
+          const validateEmail = (email) => {
+            return email.match(
+              /^(?=.{1,254}$)(?=.{1,64}@)[a-zA-Z0-9!#$%&'*+/=?^_`{|}~-]+(?:\.[a-zA-Z0-9!#$%&'*+/=?^_`{|}~-]+)*@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$/
+            );
+          };
 
-          <div class="grid-item">
-            <h2>Counter</h2>
-            <ion-input label="Email" counter="true" maxlength="100"></ion-input>
-          </div>
+          const validate = (ev) => {
+            const value = ev.target.value;
 
-          <div class="grid-item">
-            <h2>Custom Counter</h2>
-            <ion-input id="custom-counter" label="Email" counter="true" maxlength="100"></ion-input>
-          </div>
+            input.classList.remove('ion-valid');
+            input.classList.remove('ion-invalid');
 
-          <div class="grid-item">
-            <h2>Counter with Helper</h2>
-            <ion-input label="Email" counter="true" maxlength="100" helper-text="Enter an email"></ion-input>
-          </div>
+            if (value === '') return;
 
-          <div class="grid-item">
-            <h2>Counter with Error</h2>
-            <ion-input
-              class="ion-touched ion-invalid"
-              label="Email"
-              counter="true"
-              maxlength="100"
-              error-text="Please enter a valid email"
-            ></ion-input>
-          </div>
-        </div>
+            validateEmail(value) ? input.classList.add('ion-valid') : input.classList.add('ion-invalid');
+          };
 
-        <script>
-          const customCounterInput = document.querySelector('ion-input#custom-counter');
-          customCounterInput.counterFormatter = (inputLength, maxLength) => {
-            const length = maxLength - inputLength;
-            return `${maxLength - inputLength} characters left`;
+          const markTouched = () => {
+            input.classList.add('ion-touched');
           };
         </script>
       </ion-content>