From b383824934c744c1f312940c83e56657275f9766 Mon Sep 17 00:00:00 2001
From: zepumph <michael.kauzmann@colorado.edu>
Date: Fri, 24 Jul 2020 10:55:11 -0800
Subject: [PATCH] clear dynamic element containers based on `isStateInScope`,
 https://github.com/phetsims/tandem/issues/193

---
 js/PhetioDynamicElementContainer.js | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/js/PhetioDynamicElementContainer.js b/js/PhetioDynamicElementContainer.js
index 6017ffe0..6dee9c5a 100644
--- a/js/PhetioDynamicElementContainer.js
+++ b/js/PhetioDynamicElementContainer.js
@@ -122,16 +122,12 @@ class PhetioDynamicElementContainer extends PhetioObject {
       const phetioStateEngine = phet.phetio.phetioEngine.phetioStateEngine;
 
       // On state start, clear out the container and set to defer notifications.
-      phetioStateEngine.onBeforeStateSetEmitter.addListener( phetioIDsToSet => {
-        for ( let i = 0; i < phetioIDsToSet.length; i++ ) {
-          const phetioID = phetioIDsToSet[ i ];
-          if ( phetioID.startsWith( this.tandem.phetioID ) ) {
-
-            // specify that this is from state setting
-            this.clear( { fromStateSetting: true } );
-            this.setNotificationsDeferred( true );
-            return;
-          }
+      phetioStateEngine.onBeforeStateSetEmitter.addListener( isInStateScope => {
+
+        // Only clear if this PhetioDynamicElementContainer is in scope of the state to be set
+        if ( isInStateScope( this.tandem ) ) {
+          this.clear( { fromStateSetting: true } );
+          this.setNotificationsDeferred( true );
         }
       } );