fix(menu): proper focus styling when opened by tap on a touch device

src/lib/menu/menu-trigger.ts

@@ -72,6 +72,7 @@ export const MENU_PANEL_TOP_PADDING = 8;
     'aria-haspopup': 'true',
     '[attr.aria-expanded]': 'menuOpen || null',
     '(mousedown)': '_handleMousedown($event)',
+    '(touchstart)': '_openedBy = "touch"',
     '(keydown)': '_handleKeydown($event)',
     '(click)': '_handleClick($event)',
   },
@@ -87,7 +88,7 @@ export class MatMenuTrigger implements AfterContentInit, OnDestroy {
 
   // Tracking input type is necessary so it's possible to only auto-focus
   // the first item of the list when the menu is opened via the keyboard
-  private _openedByMouse: boolean = false;
+  _openedBy: 'mouse' | 'touch' | null = null;
 
   /**
    * @deprecated
@@ -281,7 +282,7 @@ export class MatMenuTrigger implements AfterContentInit, OnDestroy {
     this.menu.direction = this.dir;
     this._setMenuElevation();
     this._setIsMenuOpen(true);
-    this.menu.focusFirstItem(this._openedByMouse ? 'mouse' : 'program');
+    this.menu.focusFirstItem(this._openedBy || 'program');
   }
 
   /** Updates the menu elevation based on the amount of parent menus that it has. */
@@ -309,15 +310,15 @@ export class MatMenuTrigger implements AfterContentInit, OnDestroy {
     // We should reset focus if the user is navigating using a keyboard or
     // if we have a top-level trigger which might cause focus to be lost
     // when clicking on the backdrop.
-    if (!this._openedByMouse) {
+    if (!this._openedBy) {
       // Note that the focus style will show up both for `program` and
       // `keyboard` so we don't have to specify which one it is.
       this.focus();
     } else if (!this.triggersSubmenu()) {
-      this.focus('mouse');
+      this.focus(this._openedBy);
     }
 
-    this._openedByMouse = false;
+    this._openedBy = null;
   }
 
   // set state rather than toggle to support triggers sharing a menu
@@ -459,7 +460,7 @@ export class MatMenuTrigger implements AfterContentInit, OnDestroy {
     if (!isFakeMousedownFromScreenReader(event)) {
       // Since right or middle button clicks won't trigger the `click` event,
       // we shouldn't consider the menu as opened by mouse in those cases.
-      this._openedByMouse = event.button === 0;
+      this._openedBy = event.button === 0 ? 'mouse' : null;
 
       // Since clicking on the trigger won't close the menu if it opens a sub-menu,
       // we should prevent focus from moving onto it via click to avoid the
@@ -508,7 +509,7 @@ export class MatMenuTrigger implements AfterContentInit, OnDestroy {
         delay(0, asapScheduler)
       )
       .subscribe(() => {
-        this._openedByMouse = true;
+        this._openedBy = 'mouse';
 
         // If the same menu is used between multiple triggers, it might still be animating
         // while the new trigger tries to re-open it. Wait for the animation to finish

src/lib/menu/menu.spec.ts

@@ -164,6 +164,24 @@ describe('MatMenu', () => {
     expect(document.activeElement).toBe(triggerEl);
   }));
 
+  it('should restore focus to the root trigger when the menu was opened by touch', fakeAsync(() => {
+    const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
+    fixture.detectChanges();
+
+    const triggerEl = fixture.componentInstance.triggerEl.nativeElement;
+    dispatchFakeEvent(triggerEl, 'touchstart');
+    triggerEl.click();
+    fixture.detectChanges();
+
+    expect(overlayContainerElement.querySelector('.mat-menu-panel')).toBeTruthy();
+
+    fixture.componentInstance.trigger.closeMenu();
+    fixture.detectChanges();
+    flush();
+
+    expect(document.activeElement).toBe(triggerEl);
+  }));
+
   it('should scroll the panel to the top on open, when it is scrollable', fakeAsync(() => {
     const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
     fixture.detectChanges();
@@ -247,6 +265,27 @@ describe('MatMenu', () => {
       focusMonitor.stopMonitoring(triggerEl);
     }));
 
+    it('should set the proper focus origin when restoring focus after opening by touch',
+      fakeAsync(() => {
+        const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
+        fixture.detectChanges();
+        const triggerEl = fixture.componentInstance.triggerEl.nativeElement;
+
+        dispatchMouseEvent(triggerEl, 'touchstart');
+        triggerEl.click();
+        fixture.detectChanges();
+        patchElementFocus(triggerEl);
+        focusMonitor.monitor(triggerEl, false);
+        fixture.componentInstance.trigger.closeMenu();
+        fixture.detectChanges();
+        tick(500);
+        fixture.detectChanges();
+        flush();
+
+        expect(triggerEl.classList).toContain('cdk-touch-focused');
+        focusMonitor.stopMonitoring(triggerEl);
+      }));
+
   it('should close the menu when pressing ESCAPE', fakeAsync(() => {
     const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
     fixture.detectChanges();
@@ -380,6 +419,21 @@ describe('MatMenu', () => {
     expect(fixture.componentInstance.items.first.focus).toHaveBeenCalledWith('mouse');
   }));
 
+  it('should set the proper focus origin when opening by touch', fakeAsync(() => {
+    const fixture = createComponent(SimpleMenu, [], [FakeIcon]);
+    fixture.detectChanges();
+    spyOn(fixture.componentInstance.items.first, 'focus').and.callThrough();
+
+    const triggerEl = fixture.componentInstance.triggerEl.nativeElement;
+
+    dispatchMouseEvent(triggerEl, 'touchstart');
+    triggerEl.click();
+    fixture.detectChanges();
+    flush();
+
+    expect(fixture.componentInstance.items.first.focus).toHaveBeenCalledWith('touch');
+  }));
+
   it('should close the menu when using the CloseScrollStrategy', fakeAsync(() => {
     const scrolledSubject = new Subject();
     const fixture = createComponent(SimpleMenu,  [