在Angular更新图像后，需要调用Angular的“changeDetectorRef.detectChanges()”方法来检测变化并刷新UI。在组件中注入ChangeDetectorRef服务并在图像更新后调用detectChanges()方法即可。

示例代码：

import { Component, OnInit, ChangeDetectorRef } from '@angular/core';
import { ProductService } from './product.service';
import { Product } from './product';

@Component({
    selector: 'app-product-edit',
    templateUrl: './product-edit.component.html',
    styleUrls: ['./product-edit.component.css']
})
export class ProductEditComponent implements OnInit {
    product: Product;
    imageToUpload: File;
    imageUrl: string;

    constructor(private productService: ProductService, private changeDetectorRef: ChangeDetectorRef) { }

    ngOnInit() {
        this.product = this.productService.getProductById(1);
        this.imageUrl = this.product.imageUrl;
    }

    handleImageInput(files: FileList) {
        this.imageToUpload = files.item(0);
    }

    updateProduct() {
        if (this.imageToUpload) {
            this.productService.uploadImage(this.imageToUpload).subscribe((imageUrl: string) => {
                this.product.imageUrl = imageUrl;
                this.imageUrl = imageUrl;
                this.changeDetectorRef.detectChanges();
            });
        }
        this.productService.updateProduct(this.product).subscribe();
    }
}