From 5ef1869a10b3434bfd36b038fbf4164b88bf70da Mon Sep 17 00:00:00 2001
From: Jochen Winzer <jw@winzer-sw.de>
Date: Wed, 4 Nov 2020 09:38:53 +0100
Subject: [PATCH] Bug fix preventing undesired recreation of poll-collection
 and poll-votes on poll change.

---
 .../components/poll-collection/poll-collection.component.html | 2 +-
 .../components/poll-collection/poll-collection.component.ts   | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/client/src/app/site/cinema/components/poll-collection/poll-collection.component.html b/client/src/app/site/cinema/components/poll-collection/poll-collection.component.html
index 6010bddc5..797f4f5ed 100644
--- a/client/src/app/site/cinema/components/poll-collection/poll-collection.component.html
+++ b/client/src/app/site/cinema/components/poll-collection/poll-collection.component.html
@@ -1,4 +1,4 @@
-<mat-card class="os-card" *ngFor="let poll of polls">
+<mat-card class="os-card" *ngFor="let poll of polls; trackBy: identifyPoll">
     <p class="subtitle-text">
         <a [routerLink]="getPollDetailLink(poll)" [state]="{ back: 'true' }">{{ getPollVoteTitle(poll) }}</a>
     </p>
diff --git a/client/src/app/site/cinema/components/poll-collection/poll-collection.component.ts b/client/src/app/site/cinema/components/poll-collection/poll-collection.component.ts
index 3d4c93350..5aec27166 100644
--- a/client/src/app/site/cinema/components/poll-collection/poll-collection.component.ts
+++ b/client/src/app/site/cinema/components/poll-collection/poll-collection.component.ts
@@ -53,6 +53,10 @@ export class PollCollectionComponent extends BaseViewComponentDirective implemen
         );
     }
 
+    public identifyPoll(index: number, poll: ViewBasePoll): number {
+        return poll.id;
+    }
+
     public getPollVoteTitle(poll: ViewBasePoll): string {
         const contentObject = poll.getContentObject();
         const listTitle = contentObject.getListTitle();