ionic-team · thetaPC · Mar 11, 2025 · Mar 6, 2025 · Mar 6, 2025 · Mar 6, 2025
diff --git a/docs/api/select.md b/docs/api/select.md
@@ -253,6 +253,16 @@ import TypeaheadExample from '@site/static/usage/v8/select/typeahead/index.md';
 
 <TypeaheadExample />
 
+## Helper & Error Text
+
+Helper and error text can be used inside of a select with the `helperText` and `errorText` property. The error text will not be displayed unless the `ion-invalid` and `ion-touched` classes are added to the `ion-select`. This ensures errors are not shown before the user has a chance to enter data.
+
+In Angular, this is done automatically through form validation. In JavaScript, React and Vue, the class needs to be manually added based on your own validation.
+
+import HelperError from '@site/static/usage/v8/select/helper-error/index.md';
+
+<HelperError />
+
 ## Interfaces
 
 ### SelectChangeEventDetail

diff --git a/static/code/stackblitz/v8/angular/package.json b/static/code/stackblitz/v8/angular/package.json
@@ -15,8 +15,8 @@
     "@angular/platform-browser": "^19.0.0",
     "@angular/platform-browser-dynamic": "^19.0.0",
     "@angular/router": "^19.0.0",
-    "@ionic/angular": "^8.0.0",
-    "@ionic/core": "^8.0.0",
+    "@ionic/angular": "8.4.4-dev.11741289071.1e8e1c3f",
+    "@ionic/core": "8.4.4-dev.11741289071.1e8e1c3f",
     "ionicons": "7.4.0",
     "rxjs": "^7.8.1",
     "tslib": "^2.5.0",

diff --git a/static/code/stackblitz/v8/html/package.json b/static/code/stackblitz/v8/html/package.json
@@ -1,6 +1,6 @@
 {
   "dependencies": {
-    "@ionic/core": "8.4.1",
+    "@ionic/core": "8.4.4-dev.11741289071.1e8e1c3f",
     "ionicons": "7.4.0"
   }
 }
diff --git a/static/code/stackblitz/v8/react/package.json b/static/code/stackblitz/v8/react/package.json
@@ -3,8 +3,8 @@
   "version": "0.1.0",
   "private": true,
   "dependencies": {
-    "@ionic/react": "8.4.1",
-    "@ionic/react-router": "8.4.1",
+    "@ionic/react": "8.4.4-dev.11741289071.1e8e1c3f",
+    "@ionic/react-router": "8.4.4-dev.11741289071.1e8e1c3f",
     "@types/node": "^22.0.0",
     "@types/react": "^18.0.9",
     "@types/react-dom": "^18.0.4",

diff --git a/static/code/stackblitz/v8/vue/package.json b/static/code/stackblitz/v8/vue/package.json
@@ -8,8 +8,8 @@
     "preview": "vite preview"
   },
   "dependencies": {
-    "@ionic/vue": "8.4.1",
-    "@ionic/vue-router": "8.4.1",
+    "@ionic/vue": "8.4.4-dev.11741289071.1e8e1c3f",
+    "@ionic/vue-router": "8.4.4-dev.11741289071.1e8e1c3f",
     "vue": "^3.2.25",
     "vue-router": "4.5.0"
   },

diff --git a/static/usage/v8/select/helper-error/angular/example_component_html.md b/static/usage/v8/select/helper-error/angular/example_component_html.md
@@ -0,0 +1,19 @@
+```html
+<form [formGroup]="myForm" (ngSubmit)="onSubmit()">
+  <ion-select
+    formControlName="favFruit"
+    label="Default label"
+    placeholder="Favorite Fruit"
+    helperText="Select your favorite fruit"
+    errorText="This field is required"
+  >
+    <ion-select-option value="apple">Apple</ion-select-option>
+    <ion-select-option value="banana">Banana</ion-select-option>
+    <ion-select-option value="orange">Orange</ion-select-option>
+  </ion-select>
+
+  <br />
+
+  <ion-button type="submit" size="small">Submit</ion-button>
+</form>
+```
diff --git a/static/usage/v8/select/helper-error/angular/example_component_ts.md b/static/usage/v8/select/helper-error/angular/example_component_ts.md
@@ -0,0 +1,29 @@
+```ts
+import { Component } from '@angular/core';
+import { FormBuilder, FormGroup, Validators, ReactiveFormsModule } from '@angular/forms';
+import { IonSelect, IonSelectOption, IonButton } from '@ionic/angular/standalone';
+
+@Component({
+  selector: 'app-example',
+  standalone: true,
+  imports: [IonSelect, IonSelectOption, IonButton, ReactiveFormsModule],
+  templateUrl: './example.component.html',
+  styleUrl: './example.component.css',
+})
+export class ExampleComponent {
+  myForm: FormGroup;
+
+  constructor(private fb: FormBuilder) {
+    this.myForm = this.fb.group({
+      favFruit: ['', Validators.required],
+    });
+  }
+
+  onSubmit() {
+    // Mark the control as touched to trigger the error message.
+    // This is needed if the user submits the form without interacting
+    // with the select.
+    this.myForm.get('favFruit')!.markAsTouched();
+  }
+}
+```
diff --git a/static/usage/v8/select/helper-error/demo.html b/static/usage/v8/select/helper-error/demo.html
@@ -0,0 +1,74 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Input</title>
+    <link rel="stylesheet" href="../../common.css" />
+    <script src="../../common.js"></script>
+    <script
+      type="module"
+      src="https://cdn.jsdelivr.net/npm/@ionic/core@8.4.4-dev.11741289071.1e8e1c3f/dist/ionic/ionic.esm.js"
+    ></script>
+    <link
+      rel="stylesheet"
+      href="https://cdn.jsdelivr.net/npm/@ionic/core@8.4.4-dev.11741289071.1e8e1c3f/css/ionic.bundle.css"
+    />
+  </head>
+
+  <body>
+    <div class="container">
+      <form id="my-form">
+        <ion-select
+          label="Default label"
+          placeholder="Favorite Fruit"
+          helper-text="Select your favorite fruit"
+          error-text="This field is required"
+        >
+          <ion-select-option value="apple">Apple</ion-select-option>
+          <ion-select-option value="banana">Banana</ion-select-option>
+          <ion-select-option value="orange">Orange</ion-select-option>
+        </ion-select>
+
+        <br />
+
+        <ion-button type="submit" size="small">Submit</ion-button>
+      </form>
+    </div>
+
+    <script>
+      const form = document.getElementById('my-form');
+      const favFruit = form.querySelector('ion-select');
+
+      form.addEventListener('submit', (event) => submit(event));
+      favFruit.addEventListener('ionChange', (event) => validateSelect(event));
+      favFruit.addEventListener('ionBlur', () => onIonBlur({ detail: { value: favFruit.value } }));
+
+      const validateSelect = (event) => {
+        if (!event.detail.value) {
+          favFruit.classList.add('ion-invalid');
+          favFruit.classList.remove('ion-valid');
+        } else {
+          favFruit.classList.remove('ion-invalid');
+          favFruit.classList.add('ion-valid');
+        }
+      };
+
+      const markTouched = () => {
+        favFruit.classList.add('ion-touched');
+      };
+
+      const onIonBlur = (event) => {
+        markTouched();
+        validateSelect(event);
+      };
+
+      const submit = (event) => {
+        event.preventDefault();
+
+        markTouched();
+        validateSelect({ detail: { value: favFruit.value } });
+      };
+    </script>
+  </body>
+</html>
diff --git a/static/usage/v8/select/helper-error/index.md b/static/usage/v8/select/helper-error/index.md
@@ -0,0 +1,24 @@
+import Playground from '@site/src/components/global/Playground';
+
+import javascript from './javascript.md';
+import react from './react.md';
+import vue from './vue.md';
+
+import angular_example_component_html from './angular/example_component_html.md';
+import angular_example_component_ts from './angular/example_component_ts.md';
+
+<Playground
+  version="8"
+  code={{
+    javascript,
+    react,
+    vue,
+    angular: {
+      files: {
+        'src/app/example.component.html': angular_example_component_html,
+        'src/app/example.component.ts': angular_example_component_ts,
+      },
+    },
+  }}
+  src="usage/v8/select/helper-error/demo.html"
+/>
diff --git a/static/usage/v8/select/helper-error/javascript.md b/static/usage/v8/select/helper-error/javascript.md
@@ -0,0 +1,53 @@
+```html
+<form id="my-form">
+  <ion-select
+    label="Default label"
+    placeholder="Favorite Fruit"
+    helper-text="Select your favorite fruit"
+    error-text="This field is required"
+  >
+    <ion-select-option value="apple">Apple</ion-select-option>
+    <ion-select-option value="banana">Banana</ion-select-option>
+    <ion-select-option value="orange">Orange</ion-select-option>
+  </ion-select>
+
+  <br />
+
+  <ion-button type="submit" size="small">Submit</ion-button>
+</form>
+
+<script>
+  const form = document.getElementById('my-form');
+  const favFruit = form.querySelector('ion-select');
+
+  form.addEventListener('submit', (event) => submit(event));
+  favFruit.addEventListener('ionChange', (event) => validateSelect(event));
+  favFruit.addEventListener('ionBlur', () => onIonBlur({ detail: { value: favFruit.value } }));
+
+  const validateSelect = (event) => {
+    if (!event.detail.value) {
+      favFruit.classList.add('ion-invalid');
+      favFruit.classList.remove('ion-valid');
+    } else {
+      favFruit.classList.remove('ion-invalid');
+      favFruit.classList.add('ion-valid');
+    }
+  };
+
+  const markTouched = () => {
+    favFruit.classList.add('ion-touched');
+  };
+
+  const onIonBlur = (event) => {
+    markTouched();
+    validateSelect(event);
+  };
+
+  const submit = (event) => {
+    event.preventDefault();
+
+    markTouched();
+    validateSelect({ detail: { value: favFruit.value } });
+  };
+</script>
+```
diff --git a/static/usage/v8/select/helper-error/react.md b/static/usage/v8/select/helper-error/react.md
@@ -0,0 +1,72 @@
+```tsx
+import React, { useRef, useState } from 'react';
+import { IonSelect, IonSelectOption, IonButton, SelectCustomEvent } from '@ionic/react';
+
+function Example() {
+  const [isTouched, setIsTouched] = useState<boolean>(false);
+  const [isValid, setIsValid] = useState<boolean | undefined>();
+
+  const favFruitRef = useRef<HTMLIonSelectElement>(null);
+
+  const validateSelect = (event: SelectCustomEvent<{ value: string }>) => {
+    setIsValid(event.detail.value ? true : false);
+  };
+
+  const markTouched = () => {
+    setIsTouched(true);
+  };
+
+  const onIonBlur = () => {
+    markTouched();
+
+    if (favFruitRef.current) {
+      validateSelect({ detail: { value: favFruitRef.current.value } } as SelectCustomEvent<{
+        value: string;
+      }>);
+    }
+  };
+
+  const submit = (event: React.FormEvent<HTMLFormElement>) => {
+    event.preventDefault();
+
+    markTouched();
+
+    if (favFruitRef.current) {
+      validateSelect({ detail: { value: favFruitRef.current.value } } as SelectCustomEvent<{
+        value: string;
+      }>);
+    }
+  };
+
+  return (
+    <>
+      <form onSubmit={submit}>
+        <IonSelect
+          ref={favFruitRef}
+          label="Default label"
+          placeholder="Favorite Fruit"
+          className={`${isValid ? 'ion-valid' : ''} ${isValid === false ? 'ion-invalid' : ''} ${
+            isTouched ? 'ion-touched' : ''
+          }`}
+          helperText="Select your favorite fruit"
+          errorText="This field is required"
+          onIonChange={(event) => validateSelect(event)}
+          onIonBlur={onIonBlur}
+        >
+          <IonSelectOption value="apple">Apple</IonSelectOption>
+          <IonSelectOption value="banana">Banana</IonSelectOption>
+          <IonSelectOption value="orange">Orange</IonSelectOption>
+        </IonSelect>
+
+        <br />
+
+        <IonButton type="submit" size="small">
+          Submit
+        </IonButton>
+      </form>
+    </>
+  );
+}
+
+export default Example;
+```