refactor: handle home/end presses through key manager (#19955)

Based on top of #19834, changes the places where we were handling home/end to go through the key manager.

Also allows `withHomeAndEnd` to be turned off, similarly to what we're doing with the other methods.

Author: crisbeto

src/cdk-experimental/listbox/listbox.ts

@@ -16,16 +16,7 @@ import {
   QueryList
 } from '@angular/core';
 import {ActiveDescendantKeyManager, Highlightable, ListKeyManagerOption} from '@angular/cdk/a11y';
-import {
-  DOWN_ARROW,
-  END,
-  ENTER,
-  HOME,
-  LEFT_ARROW,
-  RIGHT_ARROW,
-  SPACE,
-  UP_ARROW
-} from '@angular/cdk/keycodes';
+import {DOWN_ARROW, ENTER, SPACE, UP_ARROW, LEFT_ARROW, RIGHT_ARROW} from '@angular/cdk/keycodes';
 import {BooleanInput, coerceBooleanProperty, coerceArray} from '@angular/cdk/coercion';
 import {SelectionChange, SelectionModel} from '@angular/cdk/collections';
 import {defer, merge, Observable, Subject} from 'rxjs';
@@ -340,6 +331,7 @@ export class CdkListbox<T> implements AfterContentInit, OnDestroy, OnInit, Contr
     this._listKeyManager = new ActiveDescendantKeyManager(this._options)
         .withWrap()
         .withTypeAhead()
+        .withHomeAndEnd()
         .withAllowedModifierKeys(['shiftKey']);
 
     if (this.orientation === 'vertical') {
@@ -376,11 +368,7 @@ export class CdkListbox<T> implements AfterContentInit, OnDestroy, OnInit, Contr
     const {keyCode} = event;
     const previousActiveIndex = manager.activeItemIndex;
 
-    if (keyCode === HOME || keyCode === END) {
-      event.preventDefault();
-      keyCode === HOME ? manager.setFirstItemActive() : manager.setLastItemActive();
-
-    } else if (keyCode === SPACE || keyCode === ENTER) {
+    if (keyCode === SPACE || keyCode === ENTER) {
       if (manager.activeItem && !manager.isTyping()) {
         this._toggleActiveOption();
       }

src/cdk/a11y/key-manager/list-key-manager.ts

@@ -179,11 +179,12 @@ export class ListKeyManager<T extends ListKeyManagerOption> {
   }
 
   /**
-   * Configures the key manager to focus the first and last items
-   * respectively when the Home key and End Key are pressed.
+   * Configures the key manager to activate the first and last items
+   * respectively when the Home or End key is pressed.
+   * @param enabled Whether pressing the Home or End key activates the first/last item.
    */
-  withHomeAndEnd(): this {
-    this._homeAndEnd = true;
+  withHomeAndEnd(enabled: boolean = true): this {
+    this._homeAndEnd = enabled;
     return this;
   }
 

src/cdk/stepper/stepper.ts

@@ -14,7 +14,7 @@ import {
   coerceNumberProperty,
   NumberInput
 } from '@angular/cdk/coercion';
-import {END, ENTER, hasModifierKey, HOME, SPACE} from '@angular/cdk/keycodes';
+import {ENTER, hasModifierKey, SPACE} from '@angular/cdk/keycodes';
 import {DOCUMENT} from '@angular/common';
 import {
   AfterViewInit,
@@ -350,6 +350,7 @@ export class CdkStepper implements AfterContentInit, AfterViewInit, OnDestroy {
     // AfterViewInit so we're guaranteed for both view and content children to be defined.
     this._keyManager = new FocusKeyManager<FocusableOption>(this._stepHeader)
                            .withWrap()
+                           .withHomeAndEnd()
                            .withVerticalOrientation(this._orientation === 'vertical');
 
     (this._dir ? (this._dir.change as Observable<Direction>) : observableOf<Direction>())
@@ -487,12 +488,6 @@ export class CdkStepper implements AfterContentInit, AfterViewInit, OnDestroy {
         (keyCode === SPACE || keyCode === ENTER)) {
       this.selectedIndex = manager.activeItemIndex;
       event.preventDefault();
-    } else if (keyCode === HOME) {
-      manager.setFirstItemActive();
-      event.preventDefault();
-    } else if (keyCode === END) {
-      manager.setLastItemActive();
-      event.preventDefault();
     } else {
       manager.onKeydown(event);
     }

src/material-experimental/mdc-chips/chip-grid.ts

@@ -8,7 +8,7 @@
 
 import {Directionality} from '@angular/cdk/bidi';
 import {BooleanInput, coerceBooleanProperty} from '@angular/cdk/coercion';
-import {BACKSPACE, TAB, HOME, END} from '@angular/cdk/keycodes';
+import {BACKSPACE, TAB} from '@angular/cdk/keycodes';
 import {
   AfterContentInit,
   AfterViewInit,
@@ -419,15 +419,7 @@ export class MatChipGrid extends _MatChipGridMixinBase implements AfterContentIn
       }
       event.preventDefault();
     } else if (this._originatesFromChip(event)) {
-      if (keyCode === HOME) {
-        manager.setFirstCellActive();
-        event.preventDefault();
-      } else if (keyCode === END) {
-        manager.setLastCellActive();
-        event.preventDefault();
-      } else {
-        manager.onKeydown(event);
-      }
+      manager.onKeydown(event);
     }
     this.stateChanges.next();
   }
@@ -456,6 +448,7 @@ export class MatChipGrid extends _MatChipGridMixinBase implements AfterContentIn
   /** Initializes the key manager to manage focus. */
   private _initKeyManager() {
     this._keyManager = new GridFocusKeyManager(this._chips)
+      .withHomeAndEnd()
       .withDirectionality(this._dir ? this._dir.value : 'ltr');
 
     if (this._dir) {

src/material-experimental/mdc-chips/chip-listbox.ts

@@ -9,7 +9,6 @@
 import {FocusKeyManager} from '@angular/cdk/a11y';
 import {Directionality} from '@angular/cdk/bidi';
 import {BooleanInput, coerceBooleanProperty} from '@angular/cdk/coercion';
-import {END, HOME} from '@angular/cdk/keycodes';
 import {
   AfterContentInit,
   ChangeDetectionStrategy,
@@ -354,15 +353,7 @@ export class MatChipListbox extends MatChipSet implements AfterContentInit, Cont
    */
   _keydown(event: KeyboardEvent) {
     if (this._originatesFromChip(event)) {
-      if (event.keyCode === HOME) {
-        this._keyManager.setFirstItemActive();
-        event.preventDefault();
-      } else if (event.keyCode === END) {
-        this._keyManager.setLastItemActive();
-        event.preventDefault();
-      } else {
-        this._keyManager.onKeydown(event);
-      }
+      this._keyManager.onKeydown(event);
     }
   }
 
@@ -457,6 +448,7 @@ export class MatChipListbox extends MatChipSet implements AfterContentInit, Cont
     this._keyManager = new FocusKeyManager<MatChip>(this._chips)
       .withWrap()
       .withVerticalOrientation()
+      .withHomeAndEnd()
       .withHorizontalOrientation(this._dir ? this._dir.value : 'ltr');
 
     if (this._dir) {

src/material-experimental/mdc-chips/grid-key-manager.ts

@@ -13,6 +13,8 @@ import {
   DOWN_ARROW,
   LEFT_ARROW,
   RIGHT_ARROW,
+  HOME,
+  END,
 } from '@angular/cdk/keycodes';
 
 
@@ -37,6 +39,7 @@ export class GridKeyManager<T> {
   private _activeRow: GridKeyManagerRow<T> | null = null;
   private _activeCell: T | null = null;
   private _dir: 'ltr' | 'rtl' = 'ltr';
+  private _homeAndEnd = false;
 
   constructor(private _rows: QueryList<GridKeyManagerRow<T>> | GridKeyManagerRow<T>[]) {
     // We allow for the rows to be an array because, in some cases, the consumer may
@@ -93,6 +96,16 @@ export class GridKeyManager<T> {
     }
   }
 
+  /**
+   * Configures the key manager to activate the first and last items
+   * respectively when the Home or End key is pressed.
+   * @param enabled Whether pressing the Home or End key activates the first/last item.
+   */
+  withHomeAndEnd(enabled: boolean = true): this {
+    this._homeAndEnd = enabled;
+    return this;
+  }
+
   /**
    * Sets the active cell depending on the key event passed in.
    * @param event Keyboard event to be used for determining which element should be active.
@@ -117,6 +130,22 @@ export class GridKeyManager<T> {
         this._dir === 'rtl' ? this.setNextColumnActive() : this.setPreviousColumnActive();
         break;
 
+      case HOME:
+        if (this._homeAndEnd) {
+          this.setFirstCellActive();
+          break;
+        } else {
+          return;
+        }
+
+      case END:
+        if (this._homeAndEnd) {
+          this.setLastCellActive();
+          break;
+        } else {
+          return;
+        }
+
       default:
         // Note that we return here, in order to avoid preventing
         // the default action of non-navigational keys.

src/material/chips/chip-list.ts

@@ -10,7 +10,7 @@ import {FocusKeyManager} from '@angular/cdk/a11y';
 import {Directionality} from '@angular/cdk/bidi';
 import {BooleanInput, coerceBooleanProperty} from '@angular/cdk/coercion';
 import {SelectionModel} from '@angular/cdk/collections';
-import {BACKSPACE, END, HOME} from '@angular/cdk/keycodes';
+import {BACKSPACE} from '@angular/cdk/keycodes';
 import {
   AfterContentInit,
   ChangeDetectionStrategy,
@@ -351,6 +351,7 @@ export class MatChipList extends _MatChipListMixinBase implements MatFormFieldCo
     this._keyManager = new FocusKeyManager<MatChip>(this.chips)
       .withWrap()
       .withVerticalOrientation()
+      .withHomeAndEnd()
       .withHorizontalOrientation(this._dir ? this._dir.value : 'ltr');
 
     if (this._dir) {
@@ -503,16 +504,7 @@ export class MatChipList extends _MatChipListMixinBase implements MatFormFieldCo
       this._keyManager.setLastItemActive();
       event.preventDefault();
     } else if (target && target.classList.contains('mat-chip')) {
-      if (event.keyCode === HOME) {
-        this._keyManager.setFirstItemActive();
-        event.preventDefault();
-      } else if (event.keyCode === END) {
-        this._keyManager.setLastItemActive();
-        event.preventDefault();
-      } else {
-        this._keyManager.onKeydown(event);
-      }
-
+      this._keyManager.onKeydown(event);
       this.stateChanges.next();
     }
   }

src/material/expansion/accordion.ts

@@ -10,7 +10,6 @@ import {Directive, Input, ContentChildren, QueryList, AfterContentInit} from '@a
 import {BooleanInput, coerceBooleanProperty} from '@angular/cdk/coercion';
 import {CdkAccordion} from '@angular/cdk/accordion';
 import {FocusKeyManager} from '@angular/cdk/a11y';
-import {HOME, END, hasModifierKey} from '@angular/cdk/keycodes';
 import {startWith} from 'rxjs/operators';
 import {
   MAT_ACCORDION,
@@ -75,27 +74,12 @@ export class MatAccordion extends CdkAccordion implements MatAccordionBase, Afte
         this._ownHeaders.notifyOnChanges();
       });
 
-    this._keyManager = new FocusKeyManager(this._ownHeaders).withWrap();
+    this._keyManager = new FocusKeyManager(this._ownHeaders).withWrap().withHomeAndEnd();
   }
 
   /** Handles keyboard events coming in from the panel headers. */
   _handleHeaderKeydown(event: KeyboardEvent) {
-    const {keyCode} = event;
-    const manager = this._keyManager;
-
-    if (keyCode === HOME) {
-      if (!hasModifierKey(event)) {
-        manager.setFirstItemActive();
-        event.preventDefault();
-      }
-    } else if (keyCode === END) {
-      if (!hasModifierKey(event)) {
-        manager.setLastItemActive();
-        event.preventDefault();
-      }
-    } else {
-      this._keyManager.onKeydown(event);
-    }
+    this._keyManager.onKeydown(event);
   }
 
   _handleHeaderFocus(header: MatExpansionPanelHeader) {

src/material/list/selection-list.spec.ts

@@ -477,7 +477,7 @@ describe('MatSelectionList without forms', () => {
       const manager = selectionList.componentInstance._keyManager;
       expect(manager.activeItemIndex).toBe(-1);
 
-      const event = createKeyboardEvent('keydown', HOME, undefined, {shift: true});
+      const event = createKeyboardEvent('keydown', HOME, undefined, {alt: true});
 
       dispatchEvent(selectionList.nativeElement, event);
       fixture.detectChanges();
@@ -501,7 +501,7 @@ describe('MatSelectionList without forms', () => {
       const manager = selectionList.componentInstance._keyManager;
       expect(manager.activeItemIndex).toBe(-1);
 
-      const event = createKeyboardEvent('keydown', END, undefined, {shift: true});
+      const event = createKeyboardEvent('keydown', END, undefined, {alt: true});
 
       dispatchEvent(selectionList.nativeElement, event);
       fixture.detectChanges();

src/material/list/selection-list.ts

@@ -12,10 +12,8 @@ import {SelectionModel} from '@angular/cdk/collections';
 import {
   A,
   DOWN_ARROW,
-  END,
   ENTER,
   hasModifierKey,
-  HOME,
   SPACE,
   UP_ARROW,
 } from '@angular/cdk/keycodes';
@@ -431,6 +429,7 @@ export class MatSelectionList extends _MatSelectionListMixinBase implements CanD
     this._keyManager = new FocusKeyManager<MatListOption>(this.options)
       .withWrap()
       .withTypeAhead()
+      .withHomeAndEnd()
       // Allow disabled items to be focusable. For accessibility reasons, there must be a way for
       // screenreader users, that allows reading the different options of the list.
       .skipPredicate(() => false)
@@ -556,13 +555,6 @@ export class MatSelectionList extends _MatSelectionListMixinBase implements CanD
           event.preventDefault();
         }
         break;
-      case HOME:
-      case END:
-        if (!hasModifier) {
-          keyCode === HOME ? manager.setFirstItemActive() : manager.setLastItemActive();
-          event.preventDefault();
-        }
-        break;
       default:
         // The "A" key gets special treatment, because it's used for the "select all" functionality.
         if (keyCode === A && this.multiple && hasModifierKey(event, 'ctrlKey') &&