feat(module:avatar): support image load error event (NG-ZORRO#3893)

close NG-ZORRO#3223

components/avatar/avatar.spec.ts

@@ -1,6 +1,7 @@
 import { Component, DebugElement, ViewChild } from '@angular/core';
 import { fakeAsync, tick, ComponentFixture, TestBed } from '@angular/core/testing';
 import { By } from '@angular/platform-browser';
+import { createFakeEvent } from 'ng-zorro-antd/core';
 
 import { NzIconTestModule } from 'ng-zorro-antd/icon/testing';
 
@@ -38,11 +39,12 @@ describe('avatar', () => {
       expect(context).not.toBeNull();
     });
     it('should tolerate error src', fakeAsync(() => {
+      const event = createFakeEvent('error');
       expect(getType(dl)).toBe('image');
       expect(context.comp.hasSrc).toBe(true);
       // Manually dispatch error.
       context.nzSrc = '';
-      context.comp.imgError();
+      context.comp.imgError(event);
       tick();
       fixture.detectChanges();
       expect(getType(dl)).toBe('icon');
@@ -55,6 +57,26 @@ describe('avatar', () => {
       expect(getType(dl)).toBe('image');
       tick();
     }));
+    it('should prevent default fallback when error src', fakeAsync(() => {
+      const event = createFakeEvent('error');
+      event.preventDefault();
+      expect(getType(dl)).toBe('image');
+      expect(context.comp.hasSrc).toBe(true);
+      // Manually dispatch error.
+      context.nzSrc = 'Invalid image src';
+      context.comp.imgError(event);
+      tick();
+      fixture.detectChanges();
+      expect(getType(dl)).toBe('image');
+      expect(context.comp.hasSrc).toBe(true);
+      context.nzSrc =
+        'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNk+P+/HgAFhAJ/wlseKgAAAABJRU5ErkJggg==';
+      tick();
+      fixture.detectChanges();
+      expect(context.comp.hasSrc).toBe(true);
+      expect(getType(dl)).toBe('image');
+      tick();
+    }));
     it('#nzSrcSet', () => {
       context.nzSrcSet = '1.png';
       fixture.detectChanges();
@@ -164,27 +186,30 @@ describe('avatar', () => {
       expect(getType(dl)).toBe('image');
     });
     it('should be show icon when image loaded error and icon exists', fakeAsync(() => {
+      const event = createFakeEvent('error');
       expect(getType(dl)).toBe('image');
-      context.comp.imgError();
+      context.comp.imgError(event);
       tick();
       fixture.detectChanges();
       expect(getType(dl)).toBe('icon');
     }));
     it('should be show text when image loaded error and icon not exists', fakeAsync(() => {
+      const event = createFakeEvent('error');
       expect(getType(dl)).toBe('image');
       context.nzIcon = null;
       fixture.detectChanges();
-      context.comp.imgError();
+      context.comp.imgError(event);
       tick();
       fixture.detectChanges();
       expect(getType(dl)).toBe('text');
     }));
     it('should be show empty when image loaded error and icon & text not exists', fakeAsync(() => {
+      const event = createFakeEvent('error');
       expect(getType(dl)).toBe('image');
       context.nzIcon = null;
       context.nzText = null;
       fixture.detectChanges();
-      context.comp.imgError();
+      context.comp.imgError(event);
       tick();
       fixture.detectChanges();
       expect(getType(dl)).toBe('');

components/avatar/doc/index.en-US.md

@@ -27,3 +27,4 @@ import { NzAvatarModule } from 'ng-zorro-antd/avatar';
 | `[nzSrcSet]` | a list of sources to use for different screen resolutions | string | - |
 | `[nzAlt]` | This attribute defines the alternative text describing the image | string | - |
 | `[nzText]` | letter type avatar | `string` | - |
+| `(nzError)` | handler when img load error, call the `preventDefault` method to prevent default fallback behavior | `EventEmitter<Event>` | - |

components/avatar/doc/index.zh-CN.md

@@ -28,3 +28,4 @@ import { NzAvatarModule } from 'ng-zorro-antd/avatar';
 | `[nzSrcSet]` | 设置图片类头像响应式资源地址 | string | - |
 | `[nzAlt]` | 图像无法显示时的替代文本 | string | - |
 | `[nzText]` | 文本类头像 | `string` | - |
+| `(nzError)` | 图片加载失败的事件，调用 `preventDefault` 方法会阻止组件默认的 fallback 行为 | `EventEmitter<Event>` | - |

components/avatar/nz-avatar.component.html

@@ -1,3 +1,3 @@
 <i nz-icon *ngIf="nzIcon && hasIcon" [type]="!oldAPIIcon && nzIcon" [ngClass]="oldAPIIcon && nzIcon"></i>
-<img *ngIf="nzSrc && hasSrc" [src]="nzSrc" [attr.srcset]="nzSrcSet" [attr.alt]="nzAlt" (error)="imgError()"/>
+<img *ngIf="nzSrc && hasSrc" [src]="nzSrc" [attr.srcset]="nzSrcSet" [attr.alt]="nzAlt" (error)="imgError($event)"/>
 <span class="ant-avatar-string" #textEl [ngStyle]="textStyles" *ngIf="nzText && hasText">{{ nzText }}</span>

components/avatar/nz-avatar.component.ts

@@ -12,8 +12,10 @@ import {
   ChangeDetectorRef,
   Component,
   ElementRef,
+  EventEmitter,
   Input,
   OnChanges,
+  Output,
   Renderer2,
   SimpleChanges,
   ViewChild,
@@ -46,6 +48,7 @@ export class NzAvatarComponent implements OnChanges {
   @Input() nzSrcSet: string;
   @Input() nzAlt: string;
   @Input() nzIcon: string;
+  @Output() readonly nzError = new EventEmitter<Event>();
 
   oldAPIIcon = true; // Make the user defined icon compatible to old API. Should be removed in 2.0.
   hasText: boolean = false;
@@ -80,17 +83,20 @@ export class NzAvatarComponent implements OnChanges {
     return this;
   }
 
-  imgError(): void {
-    this.hasSrc = false;
-    this.hasIcon = false;
-    this.hasText = false;
-    if (this.nzIcon) {
-      this.hasIcon = true;
-    } else if (this.nzText) {
-      this.hasText = true;
+  imgError($event: Event): void {
+    this.nzError.emit($event);
+    if (!$event.defaultPrevented) {
+      this.hasSrc = false;
+      this.hasIcon = false;
+      this.hasText = false;
+      if (this.nzIcon) {
+        this.hasIcon = true;
+      } else if (this.nzText) {
+        this.hasText = true;
+      }
+      this.setClass().notifyCalc();
+      this.setSizeStyle();
     }
-    this.setClass().notifyCalc();
-    this.setSizeStyle();
   }
 
   ngOnChanges(changes: SimpleChanges): void {