Add ngModel support to button toggles

src/components/button-toggle/button-toggle.spec.ts

@@ -8,14 +8,17 @@ import {
   fakeAsync,
   tick,
 } from '@angular/core/testing';
+// TODO(iveysaur): Update to @angular/forms when we have rc.2
+import {NgControl} from '@angular/common';
 import {TestComponentBuilder, ComponentFixture} from '@angular/compiler/testing';
 import {Component, DebugElement, provide} from '@angular/core';
 import {By} from '@angular/platform-browser';
 import {
   MD_BUTTON_TOGGLE_DIRECTIVES,
   MdButtonToggleGroup,
   MdButtonToggle,
-  MdButtonToggleGroupMultiple
+  MdButtonToggleGroupMultiple,
+  MdButtonToggleChange,
 } from './button-toggle';
 import {
   MdUniqueSelectionDispatcher
@@ -189,6 +192,138 @@ describe('MdButtonToggle', () => {
     });
   });
 
+  describe('button toggle group with ngModel', () => {
+    let fixture: ComponentFixture<ButtonToggleGroupWithNgModel>;
+    let groupDebugElement: DebugElement;
+    let groupNativeElement: HTMLElement;
+    let buttonToggleDebugElements: DebugElement[];
+    let buttonToggleNativeElements: HTMLElement[];
+    let groupInstance: MdButtonToggleGroup;
+    let buttonToggleInstances: MdButtonToggle[];
+    let testComponent: ButtonToggleGroupWithNgModel;
+    let groupNgControl: NgControl;
+
+    beforeEach(async(() => {
+      builder.createAsync(ButtonToggleGroupWithNgModel).then(f => {
+        fixture = f;
+        fixture.detectChanges();
+
+        testComponent = fixture.debugElement.componentInstance;
+
+        groupDebugElement = fixture.debugElement.query(By.directive(MdButtonToggleGroup));
+        groupNativeElement = groupDebugElement.nativeElement;
+        groupInstance = groupDebugElement.injector.get(MdButtonToggleGroup);
+        groupNgControl = groupDebugElement.injector.get(NgControl);
+
+        buttonToggleDebugElements = fixture.debugElement.queryAll(By.directive(MdButtonToggle));
+        buttonToggleNativeElements =
+            buttonToggleDebugElements.map(debugEl => debugEl.nativeElement);
+        buttonToggleInstances = buttonToggleDebugElements.map(debugEl => debugEl.componentInstance);
+      });
+    }));
+
+    it('should set individual radio names based on the group name', () => {
+      expect(groupInstance.name).toBeTruthy();
+      for (let buttonToggle of buttonToggleInstances) {
+        expect(buttonToggle.name).toBe(groupInstance.name);
+      }
+
+      groupInstance.name = 'new name';
+      for (let buttonToggle of buttonToggleInstances) {
+        expect(buttonToggle.name).toBe(groupInstance.name);
+      }
+    });
+
+    it('should check the corresponding button toggle on a group value change', () => {
+      expect(groupInstance.value).toBeFalsy();
+      for (let buttonToggle of buttonToggleInstances) {
+        expect(buttonToggle.checked).toBeFalsy();
+      }
+
+      groupInstance.value = 'red';
+      for (let buttonToggle of buttonToggleInstances) {
+        expect(buttonToggle.checked).toBe(groupInstance.value === buttonToggle.value);
+      }
+      expect(groupInstance.selected.value).toBe(groupInstance.value);
+    });
+
+    it('should have the correct ngControl state initially and after interaction', fakeAsync(() => {
+      expect(groupNgControl.valid).toBe(true);
+      expect(groupNgControl.pristine).toBe(true);
+      expect(groupNgControl.touched).toBe(false);
+
+      buttonToggleInstances[1].checked = true;
+      fixture.detectChanges();
+      tick();
+
+      expect(groupNgControl.valid).toBe(true);
+      expect(groupNgControl.pristine).toBe(false);
+      expect(groupNgControl.touched).toBe(false);
+
+      let nativeRadioLabel = buttonToggleDebugElements[2].query(By.css('label')).nativeElement;
+      nativeRadioLabel.click();
+      fixture.detectChanges();
+      tick();
+
+      expect(groupNgControl.valid).toBe(true);
+      expect(groupNgControl.pristine).toBe(false);
+      expect(groupNgControl.touched).toBe(true);
+    }));
+
+    it('should update the ngModel value when selecting a button toggle', fakeAsync(() => {
+      buttonToggleInstances[1].checked = true;
+      fixture.detectChanges();
+
+      tick();
+
+      expect(testComponent.modelValue).toBe('green');
+    }));
+  });
+
+  describe('button toggle group with ngModel and change event', () => {
+    let fixture: ComponentFixture<ButtonToggleGroupWithNgModel>;
+    let groupDebugElement: DebugElement;
+    let groupNativeElement: HTMLElement;
+    let buttonToggleDebugElements: DebugElement[];
+    let buttonToggleNativeElements: HTMLElement[];
+    let groupInstance: MdButtonToggleGroup;
+    let buttonToggleInstances: MdButtonToggle[];
+    let testComponent: ButtonToggleGroupWithNgModel;
+    let groupNgControl: NgControl;
+
+    beforeEach(async(() => {
+      builder.createAsync(ButtonToggleGroupWithNgModel).then(f => {
+        fixture = f;
+
+        testComponent = fixture.debugElement.componentInstance;
+
+        groupDebugElement = fixture.debugElement.query(By.directive(MdButtonToggleGroup));
+        groupNativeElement = groupDebugElement.nativeElement;
+        groupInstance = groupDebugElement.injector.get(MdButtonToggleGroup);
+        groupNgControl = groupDebugElement.injector.get(NgControl);
+
+        buttonToggleDebugElements = fixture.debugElement.queryAll(By.directive(MdButtonToggle));
+        buttonToggleNativeElements =
+            buttonToggleDebugElements.map(debugEl => debugEl.nativeElement);
+        buttonToggleInstances = buttonToggleDebugElements.map(debugEl => debugEl.componentInstance);
+
+        fixture.detectChanges();
+      });
+    }));
+
+    it('should update the model before firing change event', fakeAsync(() => {
+      expect(testComponent.modelValue).toBeUndefined();
+      expect(testComponent.lastEvent).toBeUndefined();
+
+      groupInstance.value = 'red';
+      fixture.detectChanges();
+
+      tick();
+      expect(testComponent.modelValue).toBe('red');
+      expect(testComponent.lastEvent.value).toBe('red');
+    }));
+  });
+
   describe('inside of a multiple selection group', () => {
     let fixture: ComponentFixture<ButtonTogglesInsideButtonToggleGroupMultiple>;
     let groupDebugElement: DebugElement;
@@ -318,6 +453,26 @@ class ButtonTogglesInsideButtonToggleGroup {
   groupValue: string = null;
 }
 
+@Component({
+  directives: [MD_BUTTON_TOGGLE_DIRECTIVES],
+  template: `
+  <md-button-toggle-group [(ngModel)]="modelValue" (change)="lastEvent = $event">
+    <md-button-toggle *ngFor="let option of options" [value]="option.value">
+      {{option.label}}
+    </md-button-toggle>
+  </md-button-toggle-group>
+  `
+})
+class ButtonToggleGroupWithNgModel {
+  modelValue: string;
+  options = [
+    {label: 'Red', value: 'red'},
+    {label: 'Green', value: 'green'},
+    {label: 'Blue', value: 'blue'},
+  ];
+  lastEvent: MdButtonToggleChange;
+}
+
 @Component({
   directives: [MD_BUTTON_TOGGLE_DIRECTIVES],
   template: `

src/components/button-toggle/button-toggle.ts

@@ -1,26 +1,43 @@
 import {
-  Component,
-  ContentChildren,
-  Directive,
-  EventEmitter,
-  HostBinding,
-  Input,
-  OnInit,
-  Optional,
-  Output,
-  QueryList,
-  ViewEncapsulation,
-  forwardRef
+    Component,
+    ContentChildren,
+    Directive,
+    EventEmitter,
+    HostBinding,
+    Input,
+    OnInit,
+    Optional,
+    Output,
+    Provider,
+    QueryList,
+    ViewEncapsulation,
+    forwardRef
 } from '@angular/core';
+// TODO(iveysaur): Update to @angular/forms when we have rc.2
+import {
+    NG_VALUE_ACCESSOR,
+    ControlValueAccessor,
+} from '@angular/common';
 import {Observable} from 'rxjs/Observable';
 import {
-  MdUniqueSelectionDispatcher
+    MdUniqueSelectionDispatcher
 } from '@angular2-material/core/coordination/unique-selection-dispatcher';
 import {BooleanFieldValue} from '@angular2-material/core/annotations/field-value';
 
 export type ToggleType = 'checkbox' | 'radio';
 
 
+
+/**
+ * Provider Expression that allows md-button-toggle-group to register as a ControlValueAccessor.
+ * This allows it to support [(ngModel)].
+ */
+export const MD_BUTTON_TOGGLE_GROUP_VALUE_ACCESSOR = new Provider(
+    NG_VALUE_ACCESSOR, {
+      useExisting: forwardRef(() => MdButtonToggleGroup),
+      multi: true
+    });
+
 var _uniqueIdCounter = 0;
 
 /** A simple change event emitted by either MdButtonToggle or MdButtonToggleGroup. */
@@ -32,11 +49,12 @@ export class MdButtonToggleChange {
 /** Exclusive selection button toggle group that behaves like a radio-button group. */
 @Directive({
   selector: 'md-button-toggle-group:not([multiple])',
+  providers: [MD_BUTTON_TOGGLE_GROUP_VALUE_ACCESSOR],
   host: {
     'role': 'radiogroup',
   },
 })
-export class MdButtonToggleGroup {
+export class MdButtonToggleGroup implements ControlValueAccessor {
   /** The value for the button toggle group. Should match currently selected button toggle. */
   private _value: any = null;
 
@@ -49,6 +67,12 @@ export class MdButtonToggleGroup {
   /** The currently selected button toggle, should match the value. */
   private _selected: MdButtonToggle = null;
 
+  /** The method to be called in order to update ngModel. */
+  private _controlValueAccessorChangeFn: (value: any) => void = (value) => {};
+
+  /** onTouch function registered via registerOnTouch (ControlValueAccessor). */
+  onTouched: () => any = () => {};
+
   /** Event emitted when the group's value changes. */
   private _change: EventEmitter<MdButtonToggleChange> = new EventEmitter<MdButtonToggleChange>();
   @Output() get change(): Observable<MdButtonToggleChange> {
@@ -66,7 +90,6 @@ export class MdButtonToggleGroup {
 
   set name(value: string) {
     this._name = value;
-
     this._updateButtonToggleNames();
   }
 
@@ -126,7 +149,9 @@ export class MdButtonToggleGroup {
         this.selected = matchingButtonToggle;
       } else if (this.value == null) {
         this.selected = null;
-        this._buttonToggles.forEach(buttonToggle => {buttonToggle.checked = false; });
+        this._buttonToggles.forEach(buttonToggle => {
+          buttonToggle.checked = false;
+        });
       }
     }
   }
@@ -136,8 +161,33 @@ export class MdButtonToggleGroup {
     let event = new MdButtonToggleChange();
     event.source = this._selected;
     event.value = this._value;
+    this._controlValueAccessorChangeFn(event.value);
     this._change.emit(event);
   }
+
+  /**
+   * Implemented as part of ControlValueAccessor.
+   * TODO: internal
+   */
+  writeValue(value: any) {
+    this.value = value;
+  }
+
+  /**
+   * Implemented as part of ControlValueAccessor.
+   * TODO: internal
+   */
+  registerOnChange(fn: (value: any) => void) {
+    this._controlValueAccessorChangeFn = fn;
+  }
+
+  /**
+   * Implemented as part of ControlValueAccessor.
+   * TODO: internal
+   */
+  registerOnTouched(fn: any) {
+    this.onTouched = fn;
+  }
 }
 
 /** Multiple selection button-toggle group. */
@@ -239,7 +289,6 @@ export class MdButtonToggle implements OnInit {
     if (this.buttonToggleGroup && this._value == this.buttonToggleGroup.value) {
       this._checked = true;
     }
-
   }
 
   get inputId(): string {
@@ -322,6 +371,7 @@ export class MdButtonToggle implements OnInit {
       // button toggle as checked.
       this.checked = true;
       this.buttonToggleGroup.selected = this;
+      this.buttonToggleGroup.onTouched();
     } else {
       this._toggle();
     }

src/demo-app/button-toggle/button-toggle-demo.html

@@ -37,3 +37,13 @@ <h1>Multiple Selection</h1>
 
 <h1>Single Toggle</h1>
 <md-button-toggle>Yes</md-button-toggle>
+
+<h1>Dynamic Exclusive Selection</h1>
+<section class="demo-section">
+  <md-button-toggle-group name="pies" [(ngModel)]="favoritePie">
+    <md-button-toggle *ngFor="let pie of pieOptions" [value]="pie">
+      {{pie}}
+    </md-button-toggle>
+  </md-button-toggle-group>
+  <p>Your favorite type of pie is: {{favoritePie}}</p>
+</section>

src/demo-app/button-toggle/button-toggle-demo.ts

@@ -12,4 +12,12 @@ import {MdIcon} from '@angular2-material/icon/icon';
   providers: [MdUniqueSelectionDispatcher],
   directives: [MD_BUTTON_TOGGLE_DIRECTIVES, MdIcon]
 })
-export class ButtonToggleDemo { }
+export class ButtonToggleDemo {
+  favoritePie = 'Apple';
+  pieOptions = [
+    'Apple',
+    'Cherry',
+    'Pecan',
+    'Lemon',
+  ];
+}