Updated to angular 11

Now compiling with strict mode in typescript
Need to error checking now

bookie/src/app/product/product-detail/product-detail.component.ts

@@ -16,11 +16,11 @@ import { ProductService } from '../product.service';
   styleUrls: ['./product-detail.component.css'],
 })
 export class ProductDetailComponent implements OnInit, AfterViewInit {
-  @ViewChild('name', { static: true }) nameElement: ElementRef;
+  @ViewChild('name', { static: true }) nameElement?: ElementRef;
   form: FormGroup;
-  menuCategories: MenuCategory[];
-  saleCategories: SaleCategory[];
-  item: Product;
+  menuCategories: MenuCategory[] = [];
+  saleCategories: SaleCategory[] = [];
+  item: Product = new Product();
 
   constructor(
     private route: ActivatedRoute,
@@ -30,10 +30,7 @@ export class ProductDetailComponent implements OnInit, AfterViewInit {
     private toaster: ToasterService,
     private ser: ProductService,
   ) {
-    this.createForm();
-  }
-
-  createForm() {
+    // Create form
     this.form = this.fb.group({
       code: { value: '', disabled: true },
       name: '',
@@ -48,13 +45,16 @@ export class ProductDetailComponent implements OnInit, AfterViewInit {
   }
 
   ngOnInit() {
-    this.route.data.subscribe(
-      (data: { item: Product; menuCategories: MenuCategory[]; saleCategories: SaleCategory[] }) => {
-        this.menuCategories = data.menuCategories;
-        this.saleCategories = data.saleCategories;
-        this.showItem(data.item);
-      },
-    );
+    this.route.data.subscribe((value) => {
+      const data = value as {
+        item: Product;
+        menuCategories: MenuCategory[];
+        saleCategories: SaleCategory[];
+      };
+      this.menuCategories = data.menuCategories;
+      this.saleCategories = data.saleCategories;
+      this.showItem(data.item);
+    });
   }
 
   showItem(item: Product) {
@@ -74,7 +74,9 @@ export class ProductDetailComponent implements OnInit, AfterViewInit {
 
   ngAfterViewInit() {
     setTimeout(() => {
-      this.nameElement.nativeElement.focus();
+      if (this.nameElement !== undefined) {
+        this.nameElement.nativeElement.focus();
+      }
     }, 0);
   }
 
@@ -91,7 +93,7 @@ export class ProductDetailComponent implements OnInit, AfterViewInit {
   }
 
   delete() {
-    this.ser.delete(this.item.id).subscribe(
+    this.ser.delete(this.item.id as string).subscribe(
       () => {
         this.toaster.show('Success', '');
         this.router.navigateByUrl('/products');