docs(forms): add radio button examples (#11676)

modules/@angular/examples/forms/ts/radioButtons/e2e_test/radio_button_spec.ts

@@ -0,0 +1,41 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {verifyNoBrowserErrors} from '../../../../_common/e2e_util';
+
+describe('radioButtons example', () => {
+  afterEach(verifyNoBrowserErrors);
+  let inputs: protractor.ElementArrayFinder;
+  let paragraphs: protractor.ElementArrayFinder;
+
+  beforeEach(() => {
+    browser.get('/forms/ts/radioButtons/index.html');
+    inputs = element.all(by.css('input'));
+    paragraphs = element.all(by.css('p'));
+  });
+
+  it('should populate the UI with initial values', () => {
+    expect(inputs.get(0).getAttribute('checked')).toEqual(null);
+    expect(inputs.get(1).getAttribute('checked')).toEqual('true');
+    expect(inputs.get(2).getAttribute('checked')).toEqual(null);
+
+    expect(paragraphs.get(0).getText()).toEqual('Form value: { "food": "lamb" }');
+    expect(paragraphs.get(1).getText()).toEqual('myFood value: lamb');
+  });
+
+  it('update model and other buttons as the UI value changes', () => {
+    inputs.get(0).click();
+
+    expect(inputs.get(0).getAttribute('checked')).toEqual('true');
+    expect(inputs.get(1).getAttribute('checked')).toEqual(null);
+    expect(inputs.get(2).getAttribute('checked')).toEqual(null);
+
+    expect(paragraphs.get(0).getText()).toEqual('Form value: { "food": "beef" }');
+    expect(paragraphs.get(1).getText()).toEqual('myFood value: beef');
+  });
+});

modules/@angular/examples/forms/ts/radioButtons/module.ts

@@ -0,0 +1,20 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {NgModule} from '@angular/core';
+import {FormsModule} from '@angular/forms';
+import {BrowserModule} from '@angular/platform-browser';
+import {RadioButtonComp} from './radio_button_example';
+
+@NgModule({
+  imports: [BrowserModule, FormsModule],
+  declarations: [RadioButtonComp],
+  bootstrap: [RadioButtonComp]
+})
+export class AppModule {
+}

modules/@angular/examples/forms/ts/radioButtons/radio_button_example.ts

@@ -0,0 +1,28 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+// #docregion TemplateDriven
+import {Component} from '@angular/core';
+
+@Component({
+  selector: 'example-app',
+  template: `
+    <form #f="ngForm">
+      <input type="radio" value="beef" name="food" [(ngModel)]="myFood"> Beef
+      <input type="radio" value="lamb" name="food" [(ngModel)]="myFood"> Lamb
+      <input type="radio" value="fish" name="food" [(ngModel)]="myFood"> Fish
+    </form>
+    
+    <p>Form value: {{ f.value | json }}</p>  <!-- {food: 'lamb' } -->
+    <p>myFood value: {{ myFood }}</p>  <!-- 'lamb' -->
+  `,
+})
+export class RadioButtonComp {
+  myFood = 'lamb';
+}
+// #enddocregion

modules/@angular/examples/forms/ts/reactiveRadioButtons/e2e_test/reactive_radio_button_spec.ts

@@ -0,0 +1,37 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {verifyNoBrowserErrors} from '../../../../_common/e2e_util';
+
+describe('radioButtons example', () => {
+  afterEach(verifyNoBrowserErrors);
+  let inputs: protractor.ElementArrayFinder;
+
+  beforeEach(() => {
+    browser.get('/forms/ts/reactiveRadioButtons/index.html');
+    inputs = element.all(by.css('input'));
+  });
+
+  it('should populate the UI with initial values', () => {
+    expect(inputs.get(0).getAttribute('checked')).toEqual(null);
+    expect(inputs.get(1).getAttribute('checked')).toEqual('true');
+    expect(inputs.get(2).getAttribute('checked')).toEqual(null);
+
+    expect(element(by.css('p')).getText()).toEqual('Form value: { "food": "lamb" }');
+  });
+
+  it('update model and other buttons as the UI value changes', () => {
+    inputs.get(0).click();
+
+    expect(inputs.get(0).getAttribute('checked')).toEqual('true');
+    expect(inputs.get(1).getAttribute('checked')).toEqual(null);
+    expect(inputs.get(2).getAttribute('checked')).toEqual(null);
+
+    expect(element(by.css('p')).getText()).toEqual('Form value: { "food": "beef" }');
+  });
+});

modules/@angular/examples/forms/ts/reactiveRadioButtons/module.ts

@@ -0,0 +1,20 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {NgModule} from '@angular/core';
+import {ReactiveFormsModule} from '@angular/forms';
+import {BrowserModule} from '@angular/platform-browser';
+import {ReactiveRadioButtonComp} from './reactive_radio_button_example';
+
+@NgModule({
+  imports: [BrowserModule, ReactiveFormsModule],
+  declarations: [ReactiveRadioButtonComp],
+  bootstrap: [ReactiveRadioButtonComp]
+})
+export class AppModule {
+}

modules/@angular/examples/forms/ts/reactiveRadioButtons/reactive_radio_button_example.ts

@@ -0,0 +1,30 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+// #docregion Reactive
+import {Component} from '@angular/core';
+import {FormControl, FormGroup} from '@angular/forms';
+
+@Component({
+  selector: 'example-app',
+  template: `
+    <form [formGroup]="form">
+      <input type="radio" formControlName="food" value="beef" > Beef
+      <input type="radio" formControlName="food" value="lamb"> Lamb
+      <input type="radio" formControlName="food" value="fish"> Fish
+    </form>
+    
+    <p>Form value: {{ form.value | json }}</p>  <!-- {food: 'lamb' } -->
+  `,
+})
+export class ReactiveRadioButtonComp {
+  form = new FormGroup({
+    food: new FormControl('lamb'),
+  });
+}
+// #enddocregion

modules/@angular/forms/src/directives/radio_control_value_accessor.ts

@@ -59,21 +59,33 @@ export class RadioControlRegistry {
 }
 
 /**
- * The accessor for writing a radio control value and listening to changes that is used by the
- * {@link NgModel}, {@link FormControlDirective}, and {@link FormControlName} directives.
+ * @whatItDoes  Writes radio control values and listens to radio control changes.
  *
- *  ### Example
- *  ```
- *  @Component({
- *    template: `
- *      <input type="radio" name="food" [(ngModel)]="food" value="chicken">
- *      <input type="radio" name="food" [(ngModel)]="food" value="fish">
- *    `
- *  })
- *  class FoodCmp {
- *    food = 'chicken';
- *  }
- *  ```
+ * Used by {@link NgModel}, {@link FormControlDirective}, and {@link FormControlName}
+ * to keep the view synced with the {@link FormControl} model.
+ *
+ * @howToUse
+ *
+ * If you have imported the {@link FormsModule} or the {@link ReactiveFormsModule}, this
+ * value accessor will be active on any radio control that has a form directive. You do
+ * **not** need to add a special selector to activate it.
+ *
+ * ### How to use radio buttons with form directives
+ *
+ * To use radio buttons in a template-driven form, you'll want to ensure that radio buttons
+ * in the same group have the same `name` attribute.  Radio buttons with different `name`
+ * attributes do not affect each other.
+ *
+ * {@example forms/ts/radioButtons/radio_button_example.ts region='TemplateDriven'}
+ *
+ * When using radio buttons in a reactive form, radio buttons in the same group should have the
+ * same `formControlName`. You can also add a `name` attribute, but it's optional.
+ *
+ * {@example forms/ts/reactiveRadioButtons/reactive_radio_button_example.ts region='Reactive'}
+ *
+ *  * **npm package**: `@angular/forms`
+ *
+ *  @stable
  */
 @Directive({
   selector:

modules/@angular/forms/src/forms.ts

@@ -10,11 +10,8 @@
  * @module
  * @description
  * This module is used for handling user input, by defining and building a {@link FormGroup} that
- * consists of
- * {@link FormControl} objects, and mapping them onto the DOM. {@link FormControl} objects can then
- * be used
- * to read information
- * from the form DOM elements.
+ * consists of {@link FormControl} objects, and mapping them onto the DOM. {@link FormControl}
+ * objects can then be used to read information from the form DOM elements.
  *
  * Forms providers are not included in default providers; you must import these providers
  * explicitly.
@@ -33,6 +30,7 @@ export {NgControlStatus, NgControlStatusGroup} from './directives/ng_control_sta
 export {NgForm} from './directives/ng_form';
 export {NgModel} from './directives/ng_model';
 export {NgModelGroup} from './directives/ng_model_group';
+export {RadioControlValueAccessor} from './directives/radio_control_value_accessor';
 export {FormControlDirective} from './directives/reactive_directives/form_control_directive';
 export {FormControlName} from './directives/reactive_directives/form_control_name';
 export {FormGroupDirective} from './directives/reactive_directives/form_group_directive';

tools/public_api_guard/forms/index.d.ts

@@ -439,6 +439,23 @@ export declare class PatternValidator implements Validator, OnChanges {
     };
 }
 
+/** @stable */
+export declare class RadioControlValueAccessor implements ControlValueAccessor, OnDestroy, OnInit {
+    formControlName: string;
+    name: string;
+    onChange: () => void;
+    onTouched: () => void;
+    value: any;
+    constructor(_renderer: Renderer, _elementRef: ElementRef, _registry: RadioControlRegistry, _injector: Injector);
+    fireUncheck(value: any): void;
+    ngOnDestroy(): void;
+    ngOnInit(): void;
+    registerOnChange(fn: (_: any) => {}): void;
+    registerOnTouched(fn: () => {}): void;
+    setDisabledState(isDisabled: boolean): void;
+    writeValue(value: any): void;
+}
+
 /** @stable */
 export declare class ReactiveFormsModule {
 }