fix(grids): handle double tap to allow editing on iOS #2538

Since iOS WebKit doesn't support dblclick and Angular's Hammer plugin doesn't
have doubletap exposed, resorting to our Hammer manager. Also prevented the
double tap to zoom on the cell as it was rather jarring.

Author: damyanpetev

projects/igniteui-angular/src/lib/core/touch.ts

@@ -20,11 +20,11 @@ export class HammerGesturesManager {
         inputClass: Hammer.TouchInput,
         recognizers: [
             [ Hammer.Pan, { threshold: 0 } ],
-            [ Hammer.Pinch, { enable: true } ],
-            [ Hammer.Rotate, { enable: true } ],
             [ Hammer.Swipe, {
                 direction: Hammer.DIRECTION_HORIZONTAL
-            }]
+            }],
+            [Hammer.Tap],
+            [Hammer.Tap, { event: 'doubletap', taps: 2 }, ['tap']]
         ]
     };
 
@@ -44,14 +44,14 @@ export class HammerGesturesManager {
     public addEventListener(element: HTMLElement,
                             eventName: string,
                             eventHandler: (eventObj) => void,
-                            options: object = null): () => void {
+                            options: HammerOptions = null): () => void {
 
         // Creating the manager bind events, must be done outside of angular
         return this._zone.runOutsideAngular(() => {
             let mc: HammerManager = this.getManagerForElement(element);
             if (mc === null) {
                 // new Hammer is a shortcut for Manager with defaults
-                mc = new Hammer(element, this.hammerOptions);
+                mc = new Hammer(element, Object.assign(this.hammerOptions, options));
                 this.addManagerForElement(element, mc);
             }
             const handler = (eventObj) => { this._zone.run(() => { eventHandler(eventObj); }); };

projects/igniteui-angular/src/lib/grids/cell.component.ts

@@ -23,6 +23,7 @@ import { State } from '../services/index';
 import { IgxGridBaseComponent, IGridEditEventArgs, IGridDataBindable } from './grid-base.component';
 import { IgxGridSelectionService, ISelectionNode, IgxGridCRUDService } from '../core/grid-selection';
 import { DeprecateProperty } from '../core/deprecateDecorators';
+import { HammerGesturesManager } from '../core/touch';
 
 /**
  * Providing reference to `IgxGridCellComponent`:
@@ -40,7 +41,8 @@ import { DeprecateProperty } from '../core/deprecateDecorators';
 @Component({
     changeDetection: ChangeDetectionStrategy.OnPush,
     selector: 'igx-grid-cell',
-    templateUrl: './cell.component.html'
+    templateUrl: './cell.component.html',
+    providers: [HammerGesturesManager]
 })
 export class IgxGridCellComponent implements OnInit, OnChanges, OnDestroy {
     private _vIndex = -1;
@@ -530,7 +532,8 @@ export class IgxGridCellComponent implements OnInit, OnChanges, OnDestroy {
         public selection: IgxSelectionAPIService,
         public cdr: ChangeDetectorRef,
         private element: ElementRef,
-        protected zone: NgZone) { }
+        protected zone: NgZone,
+        private touchManager: HammerGesturesManager) { }
 
 
     /**
@@ -552,6 +555,9 @@ export class IgxGridCellComponent implements OnInit, OnChanges, OnDestroy {
                 this.nativeElement.addEventListener('compositionend', this.compositionEndHandler);
             }
         });
+        this.touchManager.addEventListener(this.nativeElement, 'doubletap', this.onDoubleClick, {
+            cssProps: { } /* don't disable user-select, etc */
+        } as HammerOptions);
     }
 
     /**
@@ -569,6 +575,7 @@ export class IgxGridCellComponent implements OnInit, OnChanges, OnDestroy {
                 this.nativeElement.removeEventListener('compositionend', this.compositionEndHandler);
             }
         });
+        this.touchManager.destroy();
     }
 
     /**
@@ -716,7 +723,11 @@ export class IgxGridCellComponent implements OnInit, OnChanges, OnDestroy {
      * @internal
      */
     @HostListener('dblclick', ['$event'])
-    public onDoubleClick(event: MouseEvent) {
+    public onDoubleClick = (event: MouseEvent| HammerInput) => {
+        if (event.type === 'doubletap') {
+            // prevent double-tap to zoom on iOS
+            event.preventDefault();
+        }
         if (this.editable && !this.editMode && !this.row.deleted) {
             this.crudService.begin(this);
         }

projects/igniteui-angular/src/lib/grids/grid/cell.spec.ts

@@ -8,6 +8,7 @@ import { UIInteractions, wait } from '../../test-utils/ui-interactions.spec';
 import { configureTestSuite } from '../../test-utils/configure-suite';
 import { IgxStringFilteringOperand } from '../../data-operations/filtering-condition';
 import { SampleTestData } from '../../test-utils/sample-test-data.spec';
+import { HammerGesturesManager } from '../../core/touch';
 
 const DEBOUNCETIME = 30;
 
@@ -171,6 +172,7 @@ describe('IgxGrid - Cell component', () => {
 
         spyOn(grid.onDoubleClick, 'emit').and.callThrough();
         const event = new Event('dblclick');
+        spyOn(event, 'preventDefault');
         cellElem.nativeElement.dispatchEvent(event);
         const args: IGridCellEventArgs = {
             cell: firstCell,
@@ -179,6 +181,38 @@ describe('IgxGrid - Cell component', () => {
 
         fix.detectChanges();
 
+        expect(event.preventDefault).not.toHaveBeenCalled();
+        expect(grid.onDoubleClick.emit).toHaveBeenCalledWith(args);
+        expect(firstCell).toBe(fix.componentInstance.clickedCell);
+    });
+
+    it('Should handle doubletap, trigger onDoubleClick event', () => {
+        const addListenerSpy = spyOn(HammerGesturesManager.prototype, 'addEventListener');
+        const fix = TestBed.createComponent(DefaultGridComponent);
+        fix.detectChanges();
+
+        const grid = fix.componentInstance.instance;
+        const cellElem = fix.debugElement.query(By.css(CELL_CSS_CLASS));
+        const firstCell = grid.getCellByColumn(0, 'index');
+
+        // should attach 'doubletap'
+        expect(addListenerSpy.calls.count()).toBeGreaterThan(1);
+        expect(addListenerSpy).toHaveBeenCalledWith(firstCell.nativeElement, 'doubletap', firstCell.onDoubleClick, { cssProps: { } });
+
+        spyOn(grid.onDoubleClick, 'emit').and.callThrough();
+
+        const event = {
+            type: 'doubletap',
+            preventDefault: jasmine.createSpy('preventDefault')
+        };
+        firstCell.onDoubleClick(event as any);
+        const args: IGridCellEventArgs = {
+            cell: firstCell,
+            event
+        } as any;
+
+        fix.detectChanges();
+        expect(event.preventDefault).toHaveBeenCalled();
         expect(grid.onDoubleClick.emit).toHaveBeenCalledWith(args);
         expect(firstCell).toBe(fix.componentInstance.clickedCell);
     });

projects/igniteui-angular/src/lib/grids/hierarchical-grid/hierarchical-cell.component.ts

@@ -5,12 +5,14 @@ import { ChangeDetectorRef, ElementRef, ChangeDetectionStrategy, Component,
 import { IgxHierarchicalGridComponent } from './hierarchical-grid.component';
 import { IgxHierarchicalSelectionAPIService } from './selection';
 import { IgxGridSelectionService, IgxGridCRUDService } from '../../core/grid-selection';
+import { HammerGesturesManager } from '../../core/touch';
 
 @Component({
     changeDetection: ChangeDetectionStrategy.OnPush,
     preserveWhitespaces: false,
     selector: 'igx-hierarchical-grid-cell',
-    templateUrl: './../cell.component.html'
+    templateUrl: './../cell.component.html',
+    providers: [HammerGesturesManager]
 })
 export class IgxHierarchicalGridCellComponent extends IgxGridCellComponent implements OnInit {
 
@@ -25,8 +27,9 @@ export class IgxHierarchicalGridCellComponent extends IgxGridCellComponent imple
         public cdr: ChangeDetectorRef,
         private helement: ElementRef,
         protected zone: NgZone,
+        touchManager: HammerGesturesManager
         ) {
-            super(selectionService, crudService, gridAPI, selection, cdr, helement, zone);
+            super(selectionService, crudService, gridAPI, selection, cdr, helement, zone, touchManager);
             this.hSelection = <IgxHierarchicalSelectionAPIService>selection;
          }
 

projects/igniteui-angular/src/lib/grids/tree-grid/tree-cell.component.ts

@@ -7,11 +7,13 @@ import { getNodeSizeViaRange } from '../../core/utils';
 import { DOCUMENT } from '@angular/common';
 import { IgxGridBaseComponent, IGridDataBindable } from '../grid';
 import { IgxGridSelectionService, IgxGridCRUDService } from '../../core/grid-selection';
+import { HammerGesturesManager } from '../../core/touch';
 
 @Component({
     changeDetection: ChangeDetectionStrategy.OnPush,
     selector: 'igx-tree-grid-cell',
-    templateUrl: 'tree-cell.component.html'
+    templateUrl: 'tree-cell.component.html',
+    providers: [HammerGesturesManager]
 })
 export class IgxTreeGridCellComponent extends IgxGridCellComponent implements OnInit {
     private treeGridAPI: IgxTreeGridAPIService;
@@ -24,8 +26,9 @@ export class IgxTreeGridCellComponent extends IgxGridCellComponent implements On
                 cdr: ChangeDetectorRef,
                 element: ElementRef,
                 protected zone: NgZone,
+                touchManager: HammerGesturesManager,
                 @Inject(DOCUMENT) public document) {
-        super(selectionService, crudService, gridAPI, selection, cdr, element, zone);
+        super(selectionService, crudService, gridAPI, selection, cdr, element, zone, touchManager);
         this.treeGridAPI = <IgxTreeGridAPIService>gridAPI;
     }