fix(expansion-panel): make header interaction cancelable - master

CHANGELOG.md

@@ -17,6 +17,8 @@ All notable changes for each version of this project will be documented in this
     - **Breaking Change** - Deprecated the `label` property.
 - `igxGridActions`
     - Added `asMenuItems` Input for grid actions - `igx-grid-editing-actions`, `igx-grid-pinning-actions`. When set to true will render the related action buttons as separate menu items with button and label.
+- `IgxExpansionPanel`
+    - `IExpansionPanelEventArgs.panel` - Deprecated. Usе `owner` property to get a reference to the panel. 
 
 
 ### New Features
@@ -54,6 +56,9 @@ All notable changes for each version of this project will be documented in this
     - The component now utilizes the `IgxOverlayService` to position itself in the DOM.
     - An additional input property `outlet` has been added to allow users to specify custom Overlay Outlets using the `IgxOverlayOutletDirective`;
     - The `position` property now accepts values of type `IgxToastPosition` that work with strict templates.
+- `IgxExpansionPanelHeader`
+    - `onInteraction` is now cancelable
+    - Added `iconRef` property. This can be used to get a reference to the displayed expand/collapsed indicator. Returns `null` if `iconPosition` is set to `NONE`.
 
 ## 10.1.0
 

projects/igniteui-angular/src/lib/expansion-panel/README.md

@@ -81,14 +81,15 @@ The following inputs are available in the **igx-expansion-panel-header** compone
 | `role` | `string` | The `role` attribute of the header |
 | `iconPosition` | `string` | The position of the expand/collapse icon of the header |
 | `disabled` | `boolean` | Gets/sets whether the panel header is disabled (blocking user interaction) or not |
+| `iconRef` | `ElementRef` | Gets the reference to the element being used as expand/collapse indicator. If `iconPosition` is `NONE` - return `null` |
 
 
 ### Outputs
 The following outputs are available in the **igx-expansion-panel-header** component:
 
 | Name | Cancelable | Description | Parameters
 | :--- | :--- | :--- | :--- |
-| `onInteraction` | `false` | Emitted when a user interacts with the header host | `{ event: Event, panel: IgxExpansionPanelComponent }` |
+| `onInteraction` | `true` | Emitted when a user interacts with the header host | `{ event: Event, panel: IgxExpansionPanelComponent, cancel: boolean }` |
 
 ## IgxExpansionPanelBodyComponent
 ### Inputs

projects/igniteui-angular/src/lib/expansion-panel/expansion-panel-header.component.ts

@@ -9,11 +9,13 @@ import {
     EventEmitter,
     Output,
     ContentChild,
-    Inject
+    Inject,
+    ViewChild
 } from '@angular/core';
 import { IgxExpansionPanelIconDirective } from './expansion-panel.directives';
-import { IExpansionPanelEventArgs, IGX_EXPANSION_PANEL_COMPONENT, IgxExpansionPanelBase } from './expansion-panel.common';
+import { IGX_EXPANSION_PANEL_COMPONENT, IgxExpansionPanelBase, IExpansionPanelCancelableEventArgs  } from './expansion-panel.common';
 import { mkenum } from '../core/utils';
+import { IgxIconComponent } from '../icon/public_api';
 
 /**
  * @hidden
@@ -42,6 +44,25 @@ export class IgxExpansionPanelHeaderComponent {
      */
     public id = '';
 
+    /** @hidden @internal */
+    @ContentChild(IgxExpansionPanelIconDirective, { read: ElementRef })
+    private customIconRef: ElementRef;
+
+    /** @hidden @internal */
+    @ViewChild(IgxIconComponent, { read: IgxIconComponent })
+    public defaultIconRef: IgxIconComponent;
+
+    /**
+     * Returns a reference to the `igx-expansion-panel-icon` element;
+     * If `iconPosition` is `NONE` - return null;
+     */
+    public get iconRef(): ElementRef {
+        const defaultRef = this.defaultIconRef ? this.defaultIconRef.el : null;
+        const customRef = this.customIconRef ? this.customIconRef : null;
+        const renderedTemplate = this.iconTemplate ? customRef : defaultRef;
+        return this.iconPosition !== ICON_POSITION.NONE ? renderedTemplate : null;
+    }
+
     /**
      * @hidden
      */
@@ -120,7 +141,7 @@ export class IgxExpansionPanelHeaderComponent {
     /**
      * Emitted whenever a user interacts with the header host
      * ```typescript
-     *  handleInteraction(event: IExpansionPanelEventArgs) {
+     *  handleInteraction(event: IExpansionPanelCancelabelEventArgs) {
      *  ...
      * }
      * ```
@@ -131,7 +152,7 @@ export class IgxExpansionPanelHeaderComponent {
      * ```
      */
     @Output()
-    public onInteraction = new EventEmitter<IExpansionPanelEventArgs>();
+    public onInteraction = new EventEmitter<IExpansionPanelCancelableEventArgs >();
 
     /**
      * @hidden
@@ -185,7 +206,11 @@ export class IgxExpansionPanelHeaderComponent {
             evt.stopPropagation();
             return;
          }
-         this.onInteraction.emit({ event: evt, panel: this.panel });
+         const eventArgs: IExpansionPanelCancelableEventArgs  = { event: evt, panel: this.panel, owner: this.panel, cancel: false };
+         this.onInteraction.emit(eventArgs);
+         if (eventArgs.cancel === true) {
+             return;
+         }
          this.panel.toggle(evt);
          evt.preventDefault();
      }
@@ -194,17 +219,25 @@ export class IgxExpansionPanelHeaderComponent {
     @HostListener('keydown.Alt.ArrowDown', ['$event'])
     public openPanel(event: KeyboardEvent) {
         if (event.altKey) {
+            const eventArgs: IExpansionPanelCancelableEventArgs  = { event, panel: this.panel, owner: this.panel, cancel: false };
+            this.onInteraction.emit(eventArgs);
+            if (eventArgs.cancel === true) {
+                return;
+            }
             this.panel.expand(event);
-            this.onInteraction.emit({ event: event, panel: this.panel });
         }
      }
 
      /** @hidden @internal */
      @HostListener('keydown.Alt.ArrowUp', ['$event'])
      public closePanel(event: KeyboardEvent) {
         if (event.altKey) {
+            const eventArgs: IExpansionPanelCancelableEventArgs  = { event, panel: this.panel, owner: this.panel, cancel: false };
+            this.onInteraction.emit(eventArgs);
+            if (eventArgs.cancel === true) {
+                return;
+            }
             this.panel.collapse(event);
-            this.onInteraction.emit({ event: event, panel: this.panel });
         }
      }
 

projects/igniteui-angular/src/lib/expansion-panel/expansion-panel.common.ts

@@ -1,6 +1,6 @@
 import { EventEmitter, InjectionToken } from '@angular/core';
 import { AnimationReferenceMetadata } from '@angular/animations';
-import { IBaseEventArgs } from '../core/utils';
+import { CancelableEventArgs, IBaseEventArgs } from '../core/utils';
 
 export interface IgxExpansionPanelBase {
     id: string;
@@ -21,5 +21,11 @@ export const IGX_EXPANSION_PANEL_COMPONENT = new InjectionToken<IgxExpansionPane
 
 export interface IExpansionPanelEventArgs extends IBaseEventArgs {
     event: Event;
-    panel: IgxExpansionPanelBase;
+    /**
+     * @deprecated
+     * To get a reference to the panel, use `owner` instead.
+     */
+    panel?: IgxExpansionPanelBase;
 }
+
+export interface IExpansionPanelCancelableEventArgs  extends IExpansionPanelEventArgs, CancelableEventArgs {}

projects/igniteui-angular/src/lib/expansion-panel/expansion-panel.component.ts

@@ -229,7 +229,7 @@ export class IgxExpansionPanelComponent implements IgxExpansionPanelBase, AfterC
         }
         this.playCloseAnimation(
             () => {
-                this.onCollapsed.emit({ event: evt, panel: this });
+                this.onCollapsed.emit({ event: evt, panel: this, owner: this });
                 this.collapsed = true;
             }
         );
@@ -253,7 +253,7 @@ export class IgxExpansionPanelComponent implements IgxExpansionPanelBase, AfterC
         this.cdr.detectChanges();
         this.playOpenAnimation(
             () => {
-                this.onExpanded.emit({ event: evt, panel: this });
+                this.onExpanded.emit({ event: evt, panel: this, owner: this });
             }
         );
     }

projects/igniteui-angular/src/lib/expansion-panel/expansion-panel.directives.ts

@@ -1,7 +1,7 @@
 import { Directive, HostBinding } from '@angular/core';
 
 /**
- * @hidden
+ * @hidden @internal
  */
 @Directive({
     // tslint:disable-next-line:directive-selector
@@ -13,7 +13,7 @@ export class IgxExpansionPanelTitleDirective {
 }
 
 /**
- * @hidden
+ * @hidden @internal
  */
 @Directive({
     // tslint:disable-next-line:directive-selector
@@ -25,7 +25,7 @@ export class IgxExpansionPanelDescriptionDirective {
 }
 
 /**
- * @hidden
+ * @hidden @internal
  */
 @Directive({
     // tslint:disable-next-line:directive-selector

projects/igniteui-angular/src/lib/expansion-panel/expansion-panel.spec.ts

@@ -114,7 +114,7 @@ describe('igxExpansionPanel', () => {
 
             spyOn(panel.onCollapsed, 'emit');
             spyOn(panel.onExpanded, 'emit');
-            spyOn(header.onInteraction, 'emit');
+            spyOn(header.onInteraction, 'emit').and.callThrough();
             spyOn(panel, 'toggle').and.callThrough();
             spyOn(panel, 'expand').and.callThrough();
             spyOn(panel, 'collapse').and.callThrough();
@@ -130,7 +130,9 @@ describe('igxExpansionPanel', () => {
             expect(panel.expand).toHaveBeenCalledWith(mockEvent);
             expect(panel.collapse).toHaveBeenCalledTimes(0);
             expect(panel.onExpanded.emit).toHaveBeenCalledTimes(1);
-            expect(header.onInteraction.emit).toHaveBeenCalledWith({ event: mockEvent, panel: header.panel });
+            expect(header.onInteraction.emit).toHaveBeenCalledWith({
+                event: mockEvent, panel: header.panel, owner: header.panel, cancel: false
+            });
 
             header.onAction(mockEvent);
             tick();
@@ -153,6 +155,40 @@ describe('igxExpansionPanel', () => {
             expect(panel.onCollapsed.emit).toHaveBeenCalledTimes(1);
             expect(header.onInteraction.emit).toHaveBeenCalledTimes(2);
             expect(panel.onExpanded.emit).toHaveBeenCalledTimes(1);
+
+            // cancel event
+            header.disabled = false;
+            const headerSub = header.onInteraction.subscribe((event) => {
+                event.cancel = true;
+            });
+
+            // currently collapsed
+            expect(panel.collapsed).toBeTruthy();
+            header.onAction(mockEvent);
+            tick();
+            fixture.detectChanges();
+
+            // still collapsed, no additional onExpanded calls
+            expect(panel.collapsed).toBeTruthy();
+            expect(header.onInteraction.emit).toHaveBeenCalledTimes(3);
+            expect(panel.onExpanded.emit).toHaveBeenCalledTimes(1);
+
+            // expand via API
+            panel.expand();
+            tick();
+            fixture.detectChanges();
+
+            // currently expanded
+            expect(panel.collapsed).toBeFalsy();
+            header.onAction(mockEvent);
+            tick();
+            fixture.detectChanges();
+
+            // still expanded, no additional onCollapsed calls
+            headerSub.unsubscribe();
+            expect(panel.collapsed).toBeFalsy();
+            expect(header.onInteraction.emit).toHaveBeenCalledTimes(4);
+            expect(panel.onCollapsed.emit).toHaveBeenCalledTimes(1);
         }));
     });
 
@@ -447,7 +483,7 @@ describe('igxExpansionPanel', () => {
             let timesExpanded = 0;
             spyOn(panel.onCollapsed, 'emit').and.callThrough();
             spyOn(panel.onExpanded, 'emit').and.callThrough();
-            spyOn(header.onInteraction, 'emit');
+            spyOn(header.onInteraction, 'emit').and.callThrough();
             verifyPanelExpansionState(true, panel, panelContainer, panelHeader, button, timesCollapsed, timesExpanded);
 
             panelHeader.dispatchEvent(enterEvent);
@@ -511,6 +547,41 @@ describe('igxExpansionPanel', () => {
             timesCollapsed++;
             verifyPanelExpansionState(true, panel, panelContainer, panelHeader, button, timesCollapsed, timesExpanded);
             expect(header.onInteraction.emit).toHaveBeenCalledTimes(8);
+
+            // disabled interaction
+            const headerSub = header.onInteraction.subscribe((event) => {
+                event.cancel = true;
+            });
+
+            // currently collapsed
+            expect(panel.collapsed).toEqual(true);
+
+            // cancel openening
+            panelHeader.dispatchEvent(arrowDownEvent);
+            fixture.detectChanges();
+            tick();
+            // do not iterate timesExpanded
+            verifyPanelExpansionState(true, panel, panelContainer, panelHeader, button, timesCollapsed, timesExpanded);
+            expect(header.onInteraction.emit).toHaveBeenCalledTimes(9);
+
+            // open through API
+            panel.expand();
+            timesExpanded++;
+            tick();
+            fixture.detectChanges();
+
+             // currently expanded
+             expect(panel.collapsed).toEqual(false);
+
+             // cancel closing
+            panelHeader.dispatchEvent(arrowUpEvent);
+            fixture.detectChanges();
+            tick();
+            // do not iterate timesCollapsed
+            verifyPanelExpansionState(false, panel, panelContainer, panelHeader, button, timesCollapsed, timesExpanded);
+            expect(header.onInteraction.emit).toHaveBeenCalledTimes(10);
+
+            headerSub.unsubscribe();
         }));
         it('Should change panel expansion when using different methods', fakeAsync(() => {
             const fixture: ComponentFixture<IgxExpansionPanelListComponent> = TestBed.createComponent(IgxExpansionPanelListComponent);
@@ -727,15 +798,28 @@ describe('igxExpansionPanel', () => {
             expect(headerButton.children.length).toEqual(2);
             expect(iconContainer.firstElementChild.nodeName).toEqual('IGX-ICON');
             expect(titleContainer.firstElementChild.nodeName).toEqual('IGX-EXPANSION-PANEL-TITLE');
+            expect(header.iconRef).not.toBe(null);
+            expect(header.iconRef.nativeElement).toEqual(iconContainer.firstElementChild);
 
             fixture.componentInstance.customIcon = true;
             fixture.detectChanges();
 
             expect(iconContainer.firstElementChild.nodeName).toEqual('IGX-EXPANSION-PANEL-ICON');
             expect(titleContainer.firstElementChild.nodeName).toEqual('IGX-EXPANSION-PANEL-TITLE');
+            expect(header.iconRef).not.toBe(null);
+            expect(header.iconRef.nativeElement).toEqual(iconContainer.firstElementChild);
+
+            fixture.componentInstance.header.iconPosition = ICON_POSITION.NONE;
+            fixture.detectChanges();
+            expect(header.iconRef).toEqual(null);
 
             fixture.componentInstance.customIcon = false;
             fixture.detectChanges();
+            expect(header.iconRef).toEqual(null);
+
+            fixture.componentInstance.header.iconPosition = ICON_POSITION.LEFT;
+            fixture.detectChanges();
+            expect(header.iconRef).not.toBe(null);
 
             expect(iconContainer.firstElementChild.nodeName).toEqual('IGX-ICON');
             expect(titleContainer.firstElementChild.nodeName).toEqual('IGX-EXPANSION-PANEL-TITLE');