activated typescript strict mode

src/app/modules/shows/list/list-item/list-item.component.html

@@ -1,4 +1,4 @@
-<div class="list-item">
+<div class="list-item" *ngIf="show">
   <div>{{ show.date.toDate() | date: "dd.MM.yyyy" }}</div>
   <div>{{ show.showType | showType }}</div>
 </div>

src/app/modules/shows/list/list-item/list-item.component.ts

@@ -7,5 +7,5 @@ import {Show} from '../../services/show';
   styleUrls: ['./list-item.component.less'],
 })
 export class ListItemComponent {
-  @Input() public show: Show;
+  @Input() public show: Show | null = null;
 }