Added watches for when radio buttons change and the ability to set an aria label

src/app/public/modules/radio/fixtures/radio-group.component.fixture.html

@@ -1,9 +1,10 @@
 <form [formGroup]="radioForm">
   <sky-radio-group
-    ariaLabelledBy="radio-group-label"
     class="form-group radio"
     formControlName="option"
     name="option"
+    [ariaLabel]="ariaLabel"
+    [ariaLabelledBy]="ariaLabelledBy"
     [tabIndex]="tabIndex"
   >
     <legend

src/app/public/modules/radio/fixtures/radio-group.component.fixture.ts

@@ -25,6 +25,11 @@ export class SkyRadioGroupTestComponent {
   public radioForm: FormGroup;
 
   public tabIndex: number;
+
+  public ariaLabelledBy: string = 'radio-group-label';
+
+  public ariaLabel: string;
+
   public options = [
     { name: 'Lillith Corharvest', disabled: false },
     { name: 'Harima Kenji', disabled: false },
@@ -38,4 +43,13 @@ export class SkyRadioGroupTestComponent {
       option: new FormControl(this.options[0])
     });
   }
+
+  public changeOptions(): void {
+    this.options = [
+      { name: 'Lillith Corharvest', disabled: false },
+      { name: 'Hank Salizar', disabled: false },
+      { name: 'Harima Kenji', disabled: false },
+      { name: 'Harry Mckenzie', disabled: false }
+    ];
+  }
 }

src/app/public/modules/radio/radio-group.component.html

@@ -2,6 +2,7 @@
   class="sky-radio-group"
   role="radiogroup"
   [attr.aria-labelledby]="ariaLabelledBy"
+  [attr.aria-label]="ariaLabel"
 >
   <ng-content></ng-content>
 </div>

src/app/public/modules/radio/radio-group.component.spec.ts

@@ -105,6 +105,46 @@ describe('Radio group component', function () {
     }
   }));
 
+  it('should maintain tabIndex when options change', fakeAsync(function () {
+    componentInstance.tabIndex = 2;
+    fixture.detectChanges();
+    tick();
+    fixture.detectChanges();
+
+    componentInstance.changeOptions();
+    fixture.detectChanges();
+    tick();
+    fixture.detectChanges();
+
+    const radios = fixture.nativeElement.querySelectorAll('input');
+    for (let element of radios) {
+      expect(element.getAttribute('tabindex')).toBe('2');
+    }
+  }));
+
+  it('should set the radio name properties correctly', fakeAsync(() => {
+    fixture.detectChanges();
+    tick();
+    const radios = fixture.nativeElement.querySelectorAll('input');
+    for (let element of radios) {
+      expect(element.getAttribute('name')).toBe('option');
+    }
+  }));
+
+  it('should set the radio name properties correctly when options change', fakeAsync(() => {
+    fixture.detectChanges();
+    tick();
+
+    componentInstance.changeOptions();
+    fixture.detectChanges();
+    tick();
+
+    const radios = fixture.nativeElement.querySelectorAll('input');
+    for (let element of radios) {
+      expect(element.getAttribute('name')).toBe('option');
+    }
+  }));
+
   it('should maintain checked state when value is changed', fakeAsync(function () {
     fixture.detectChanges();
 
@@ -133,6 +173,48 @@ describe('Radio group component', function () {
     expect(radioDebugElement.componentInstance.checked).toBeTruthy();
   }));
 
+  it('should maintain checked state when options are changed', fakeAsync(function () {
+    fixture.detectChanges();
+
+    let newValue = {
+      name: 'Jerry Salmonella',
+      disabled: false
+    };
+
+    let radioDebugElement = fixture.debugElement.query(By.css('sky-radio'));
+    radioDebugElement.componentInstance.value = newValue;
+    fixture.detectChanges();
+    tick();
+
+    expect(radioDebugElement.componentInstance.checked).toBeTruthy();
+
+    componentInstance.changeOptions();
+
+    fixture.detectChanges();
+    tick();
+
+    expect(radioDebugElement.componentInstance.checked).toBeTruthy();
+  }));
+
+  it('should set the aria-labeledby property correctly', fakeAsync(() => {
+    fixture.detectChanges();
+    tick();
+
+    const radioGroupDiv = fixture.nativeElement.querySelector('.sky-radio-group');
+    expect(radioGroupDiv.getAttribute('aria-labelledby')).toBe('radio-group-label');
+  }));
+
+  it('should set the aria-label property correctly', fakeAsync(() => {
+    componentInstance.ariaLabel = 'radio-group-label-manual';
+    componentInstance.ariaLabelledBy = undefined;
+
+    fixture.detectChanges();
+    tick();
+
+    const radioGroupDiv = fixture.nativeElement.querySelector('.sky-radio-group');
+    expect(radioGroupDiv.getAttribute('aria-label')).toBe('radio-group-label-manual');
+  }));
+
   it('should pass accessibility', async(() => {
     fixture.detectChanges();
     fixture.whenStable().then(() => {

src/app/public/modules/radio/radio-group.component.ts

@@ -5,6 +5,7 @@ import {
   ContentChildren,
   forwardRef,
   Input,
+  OnDestroy,
   QueryList
 } from '@angular/core';
 
@@ -13,6 +14,10 @@ import {
   NG_VALUE_ACCESSOR
 } from '@angular/forms';
 
+import {
+  Subject
+} from 'rxjs/Subject';
+
 import {
   SkyRadioChange
 } from './types';
@@ -38,10 +43,13 @@ const SKY_RADIO_GROUP_CONTROL_VALUE_ACCESSOR: any = {
     SKY_RADIO_GROUP_CONTROL_VALUE_ACCESSOR
   ]
 })
-export class SkyRadioGroupComponent implements AfterContentInit, ControlValueAccessor {
+export class SkyRadioGroupComponent implements AfterContentInit, ControlValueAccessor, OnDestroy {
   @Input()
   public ariaLabelledBy: string;
 
+  @Input()
+  public ariaLabel: string;
+
   @Input()
   public set name(value: string) {
     this._name = value;
@@ -82,21 +90,34 @@ export class SkyRadioGroupComponent implements AfterContentInit, ControlValueAcc
   @ContentChildren(SkyRadioComponent, { descendants: true })
   private radios: QueryList<SkyRadioComponent>;
 
+  private ngUnsubscribe = new Subject();
+
   private _name = `sky-radio-group-${nextUniqueId++}`;
   private _value: any;
   private _tabIndex: number;
 
   public ngAfterContentInit(): void {
-    this.updateCheckedRadioFromValue();
-    this.updateRadioButtonNames();
-    this.updateRadioButtonTabIndexes();
+    this.resetRadioButtons();
 
     // Watch for radio selections.
     this.radios.forEach((radio) => {
-      radio.change.subscribe((change: SkyRadioChange) => {
-        this.writeValue(change.value);
-      });
+      radio.change
+        .takeUntil(this.ngUnsubscribe)
+        .subscribe((change: SkyRadioChange) => {
+          this.writeValue(change.value);
+        });
     });
+
+    this.radios.changes
+      .takeUntil(this.ngUnsubscribe)
+      .subscribe(() => {
+        this.resetRadioButtons();
+      });
+  }
+
+  public ngOnDestroy() {
+    this.ngUnsubscribe.next();
+    this.ngUnsubscribe.complete();
   }
 
   public writeValue(value: any): void {
@@ -145,4 +166,10 @@ export class SkyRadioGroupComponent implements AfterContentInit, ControlValueAcc
       }
     });
   }
+
+  private resetRadioButtons(): void {
+    this.updateCheckedRadioFromValue();
+    this.updateRadioButtonNames();
+    this.updateRadioButtonTabIndexes();
+  }
 }