From b358c6c44c791b1ead393a5a3d399c7efbef6722 Mon Sep 17 00:00:00 2001 From: Andrew Seguin Date: Thu, 16 Feb 2017 15:44:01 -0800 Subject: [PATCH] fix(scrollable): check if scrollable exists before unregistering (#3050) --- src/lib/core/overlay/scroll/scroll-dispatcher.ts | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/src/lib/core/overlay/scroll/scroll-dispatcher.ts b/src/lib/core/overlay/scroll/scroll-dispatcher.ts index 15cefb2d244..334ebabfa37 100644 --- a/src/lib/core/overlay/scroll/scroll-dispatcher.ts +++ b/src/lib/core/overlay/scroll/scroll-dispatcher.ts @@ -34,7 +34,6 @@ export class ScrollDispatcher { /** * Registers a Scrollable with the service and listens for its scrolled events. When the * scrollable is scrolled, the service emits the event in its scrolled observable. - * * @param scrollable Scrollable instance to be registered. */ register(scrollable: Scrollable): void { @@ -44,12 +43,13 @@ export class ScrollDispatcher { /** * Deregisters a Scrollable reference and unsubscribes from its scroll event observable. - * * @param scrollable Scrollable instance to be deregistered. */ deregister(scrollable: Scrollable): void { - this.scrollableReferences.get(scrollable).unsubscribe(); - this.scrollableReferences.delete(scrollable); + if (this.scrollableReferences.has(scrollable)) { + this.scrollableReferences.get(scrollable).unsubscribe(); + this.scrollableReferences.delete(scrollable); + } } /**