fix(menu): support focus first/last item via home/end keys

Adds support for jumping to the first/last item using the home/end keys.

Author: crisbeto

src/lib/menu/menu-directive.ts

@@ -9,7 +9,16 @@
 import {FocusKeyManager, FocusOrigin} from '@angular/cdk/a11y';
 import {Direction} from '@angular/cdk/bidi';
 import {coerceBooleanProperty} from '@angular/cdk/coercion';
-import {ESCAPE, LEFT_ARROW, RIGHT_ARROW, DOWN_ARROW, UP_ARROW} from '@angular/cdk/keycodes';
+import {
+  ESCAPE,
+  LEFT_ARROW,
+  RIGHT_ARROW,
+  DOWN_ARROW,
+  UP_ARROW,
+  HOME,
+  END,
+  hasModifierKey,
+} from '@angular/cdk/keycodes';
 import {
   AfterContentInit,
   ChangeDetectionStrategy,
@@ -258,6 +267,7 @@ export class MatMenu implements AfterContentInit, MatMenuPanel<MatMenuItem>, OnI
   /** Handle a keyboard event from the menu, delegating to the appropriate action. */
   _handleKeydown(event: KeyboardEvent) {
     const keyCode = event.keyCode;
+    const manager = this._keyManager;
 
     switch (keyCode) {
       case ESCAPE:
@@ -273,12 +283,19 @@ export class MatMenu implements AfterContentInit, MatMenuPanel<MatMenuItem>, OnI
           this.closed.emit('keydown');
         }
       break;
+      case HOME:
+      case END:
+        if (!hasModifierKey(event)) {
+          keyCode === HOME ? manager.setFirstItemActive() : manager.setLastItemActive();
+          event.preventDefault();
+        }
+      break;
       default:
         if (keyCode === UP_ARROW || keyCode === DOWN_ARROW) {
-          this._keyManager.setFocusOrigin('keyboard');
+          manager.setFocusOrigin('keyboard');
         }
 
-        this._keyManager.onKeydown(event);
+        manager.onKeydown(event);
     }
   }
 

src/lib/menu/menu.spec.ts

@@ -17,7 +17,7 @@ import {
 } from '@angular/core';
 import {Direction, Directionality} from '@angular/cdk/bidi';
 import {OverlayContainer, Overlay} from '@angular/cdk/overlay';
-import {ESCAPE, LEFT_ARROW, RIGHT_ARROW, DOWN_ARROW, TAB} from '@angular/cdk/keycodes';
+import {ESCAPE, LEFT_ARROW, RIGHT_ARROW, DOWN_ARROW, TAB, HOME, END} from '@angular/cdk/keycodes';
 import {
   MAT_MENU_DEFAULT_OPTIONS,
   MatMenu,
@@ -601,6 +601,104 @@ describe('MatMenu', () => {
     expect(overlayContainerElement.textContent).toBe('');
   }));
 
+  it('should focus the first item when pressing home', fakeAsync(() => {
+    const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
+    fixture.detectChanges();
+
+    fixture.componentInstance.trigger.openMenu();
+    fixture.detectChanges();
+
+    const panel = overlayContainerElement.querySelector('.mat-menu-panel')!;
+    const items = Array.from(panel.querySelectorAll('.mat-menu-item')) as HTMLElement[];
+    items.forEach(patchElementFocus);
+
+    // Focus the last item since focus starts from the first one.
+    items[items.length - 1].focus();
+    fixture.detectChanges();
+
+    spyOn(items[0], 'focus').and.callThrough();
+
+    const event = dispatchKeyboardEvent(panel, 'keydown', HOME);
+    fixture.detectChanges();
+
+    expect(items[0].focus).toHaveBeenCalled();
+    expect(event.defaultPrevented).toBe(true);
+    flush();
+  }));
+
+  it('should not focus the first item when pressing home with a modifier key', fakeAsync(() => {
+    const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
+    fixture.detectChanges();
+
+    fixture.componentInstance.trigger.openMenu();
+    fixture.detectChanges();
+
+    const panel = overlayContainerElement.querySelector('.mat-menu-panel')!;
+    const items = Array.from(panel.querySelectorAll('.mat-menu-item')) as HTMLElement[];
+    items.forEach(patchElementFocus);
+
+    // Focus the last item since focus starts from the first one.
+    items[items.length - 1].focus();
+    fixture.detectChanges();
+
+    spyOn(items[0], 'focus').and.callThrough();
+
+    const event = createKeyboardEvent('keydown', HOME);
+    Object.defineProperty(event, 'altKey', {get: () => true});
+
+    dispatchEvent(panel, event);
+    fixture.detectChanges();
+
+    expect(items[0].focus).not.toHaveBeenCalled();
+    expect(event.defaultPrevented).toBe(false);
+    flush();
+  }));
+
+  it('should focus the last item when pressing end', fakeAsync(() => {
+    const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
+    fixture.detectChanges();
+
+    fixture.componentInstance.trigger.openMenu();
+    fixture.detectChanges();
+
+    const panel = overlayContainerElement.querySelector('.mat-menu-panel')!;
+    const items = Array.from(panel.querySelectorAll('.mat-menu-item')) as HTMLElement[];
+    items.forEach(patchElementFocus);
+
+    spyOn(items[items.length - 1], 'focus').and.callThrough();
+
+    const event = dispatchKeyboardEvent(panel, 'keydown', END);
+    fixture.detectChanges();
+
+    expect(items[items.length - 1].focus).toHaveBeenCalled();
+    expect(event.defaultPrevented).toBe(true);
+    flush();
+  }));
+
+  it('should not focus the last item when pressing end with a modifier key', fakeAsync(() => {
+    const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
+    fixture.detectChanges();
+
+    fixture.componentInstance.trigger.openMenu();
+    fixture.detectChanges();
+
+    const panel = overlayContainerElement.querySelector('.mat-menu-panel')!;
+    const items = Array.from(panel.querySelectorAll('.mat-menu-item')) as HTMLElement[];
+    items.forEach(patchElementFocus);
+
+    spyOn(items[items.length - 1], 'focus').and.callThrough();
+
+    const event = createKeyboardEvent('keydown', END);
+    Object.defineProperty(event, 'altKey', {get: () => true});
+
+    dispatchEvent(panel, event);
+    fixture.detectChanges();
+
+    expect(items[items.length - 1].focus).not.toHaveBeenCalled();
+    expect(event.defaultPrevented).toBe(false);
+    flush();
+  }));
+
   describe('lazy rendering', () => {
     it('should be able to render the menu content lazily', fakeAsync(() => {
       const fixture = createComponent(SimpleLazyMenu);