From 20513594909222b2afed1593e2855197d7f6e2b1 Mon Sep 17 00:00:00 2001
From: Lorenzo Blasa <lblasa@fb.com>
Date: Tue, 20 Sep 2022 05:15:50 -0700
Subject: [PATCH] Unsubscribe from updates and tidy up

Summary: Remove listener on unsubscribe and tidy up comments.

Reviewed By: LukeDefeo

Differential Revision: D39575287

fbshipit-source-id: 2b4ac0bc07cfe86f5ad0e602bbba4b596230cd52
---
 .../uidebugger/observers/ApplicationTreeObserver.kt    | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/ApplicationTreeObserver.kt b/android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/ApplicationTreeObserver.kt
index adef2b362..95773f6bb 100644
--- a/android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/ApplicationTreeObserver.kt
+++ b/android/src/main/java/com/facebook/flipper/plugins/uidebugger/observers/ApplicationTreeObserver.kt
@@ -39,15 +39,19 @@ class ApplicationTreeObserver(val context: Context) : TreeObserver<ApplicationRe
           }
         }
     context.applicationRef.rootsResolver.attachListener(rootViewListener)
-    // trigger a traversal on whatever roots we have now
+    // On subscribe, trigger a traversal on whatever roots we have
     rootViewListener.onRootViewsChanged(applicationRef.rootViews)
 
+    // TODO: Subscribing to root view changes but not to activity changes.
+    // Obviously changes in activities have an effect on root views, but
+    // then it may make sense to unsubscribe the root views listener instead
+    // of activities.
+
     Log.i(LogTag, "${context.applicationRef.rootViews.size} root views")
     Log.i(LogTag, "${context.applicationRef.activitiesStack.size} activities")
   }
 
   override fun unsubscribe() {
-    // Not entirely sure this will ever happen or be needed.
-    // context.applicationRef.setActivityStackChangedListener(null)
+    context.applicationRef.rootsResolver.attachListener(null)
   }
 }