Make sure callback is still registered when calling wrappee

This caused callback methods getting run after onDestroy() problem.

Bug 2799534
Bug 3011802

Change-Id: Id505e328bbff096a9f7474c033443ff6663a5fdf

2 files changed, 23 insertions, 0 deletions

diff --git a/src/com/android/email/Controller.java b/src/com/android/email/Controller.java
index 81613204a..b200051b2 100644
--- a/src/com/android/email/Controller.java
+++ b/src/com/android/email/Controller.java
@@ -161,6 +161,7 @@ public class Controller {
      */
     public void addResultCallback(Result listener) {
         synchronized (mListeners) {
+            listener.setRegistered(true);
             mListeners.add(listener);
         }
     }
@@ -174,6 +175,7 @@ public class Controller {
      */
     public void removeResultCallback(Result listener) {
         synchronized (mListeners) {
+            listener.setRegistered(false);
             mListeners.remove(listener);
         }
     }
@@ -986,6 +988,16 @@ public class Controller {
      * made from the UI thread, so you may need further handlers to safely make UI updates.
      */
     public static abstract class Result {
+        private volatile boolean mRegistered;
+
+        private void setRegistered(boolean registered) {
+            mRegistered = registered;
+        }
+
+        protected final boolean isRegistered() {
+            return mRegistered;
+        }
+
         /**
          * Callback for updateMailboxList
          *
diff --git a/src/com/android/email/ControllerResultUiThreadWrapper.java b/src/com/android/email/ControllerResultUiThreadWrapper.java
index d4e5fd9cc..f4f949204 100644
--- a/src/com/android/email/ControllerResultUiThreadWrapper.java
+++ b/src/com/android/email/ControllerResultUiThreadWrapper.java
@@ -54,6 +54,11 @@ public class ControllerResultUiThreadWrapper<T extends Result> extends Result {
             final long attachmentId, final int progress) {
         run(new Runnable() {
             public void run() {
+                /* It's possible this callback is unregistered after this Runnable was posted and
+                 * sitting in the handler queue, so we always need to check if it's still registered
+                 * on the UI thread.
+                 */
+                if (!isRegistered()) return;
                 mWrappee.loadAttachmentCallback(result, messageId, attachmentId, progress);
             }
         });
@@ -64,6 +69,7 @@ public class ControllerResultUiThreadWrapper<T extends Result> extends Result {
             final long messageId, final int progress) {
         run(new Runnable() {
             public void run() {
+                if (!isRegistered()) return;
                 mWrappee.loadMessageForViewCallback(result, messageId, progress);
             }
         });
@@ -74,6 +80,7 @@ public class ControllerResultUiThreadWrapper<T extends Result> extends Result {
             final long messageId, final int progress) {
         run(new Runnable() {
             public void run() {
+                if (!isRegistered()) return;
                 mWrappee.sendMailCallback(result, accountId, messageId, progress);
             }
         });
@@ -84,6 +91,7 @@ public class ControllerResultUiThreadWrapper<T extends Result> extends Result {
             final long mailboxId, final int progress, final long tag) {
         run(new Runnable() {
             public void run() {
+                if (!isRegistered()) return;
                 mWrappee.serviceCheckMailCallback(result, accountId, mailboxId, progress, tag);
             }
         });
@@ -94,6 +102,7 @@ public class ControllerResultUiThreadWrapper<T extends Result> extends Result {
             final long mailboxId, final int progress, final int numNewMessages) {
         run(new Runnable() {
             public void run() {
+                if (!isRegistered()) return;
                 mWrappee.updateMailboxCallback(result, accountId, mailboxId, progress,
                         numNewMessages);
             }
@@ -105,6 +114,7 @@ public class ControllerResultUiThreadWrapper<T extends Result> extends Result {
             final int progress) {
         run(new Runnable() {
             public void run() {
+                if (!isRegistered()) return;
                 mWrappee.updateMailboxListCallback(result, accountId, progress);
             }
         });
@@ -114,6 +124,7 @@ public class ControllerResultUiThreadWrapper<T extends Result> extends Result {
     public void deleteAccountCallback(final long accountId) {
         run(new Runnable() {
             public void run() {
+                if (!isRegistered()) return;
                 mWrappee.deleteAccountCallback(accountId);
             }
         });