commit 890202bde486ca47ceb5daf4955038352384558e
author Phil Weaver <pweaver@google.com> Thu Jul 14 15:11:09 2016 -0700
committer Phil Weaver <pweaver@google.com> Tue Jul 19 16:44:28 2016 -0700
tree 7f6d17898e821a28a409c48fad170be2a6bbf950
parent d7a59636b719c38230b1c6f03e44b462463781db

Suppress exceptions for corner-case a11y events.

Apps are told to query AccessibilityManager#isEnabled before
calling sendAccessibilityEvent. If accessibility is disabled
between the two calls, an app can crash. We can guarantee that
this won't happen on a process's main thread, but guaranteeing
it for all threads is messier. Rather than add the complexity
of tracking the state for all threads, only log an error in the
corner case that an accessibility event is requested on a
thread that doesn't have the process's main looper.

Bug: 28985452
Change-Id: I8369deefd83b0a6b04936ddfce55c53147756f1f

core/java/android/view/accessibility/AccessibilityManager.java

diff --git a/core/java/android/view/accessibility/AccessibilityManager.java b/core/java/android/view/accessibility/AccessibilityManager.java
index 81ec330..2dfa8cd 100644
--- a/core/java/android/view/accessibility/AccessibilityManager.java
+++ b/core/java/android/view/accessibility/AccessibilityManager.java
@@ -305,7 +305,18 @@
                 return;
             }
             if (!mIsEnabled) {
-                throw new IllegalStateException("Accessibility off. Did you forget to check that?");
+                Looper myLooper = Looper.myLooper();
+                if (myLooper == Looper.getMainLooper()) {
+                    throw new IllegalStateException(
+                            "Accessibility off. Did you forget to check that?");
+                } else {
+                    // If we're not running on the thread with the main looper, it's possible for
+                    // the state of accessibility to change between checking isEnabled and
+                    // calling this method. So just log the error rather than throwing the
+                    // exception.
+                    Log.e(LOG_TAG, "AccessibilityEvent sent with accessibility disabled");
+                    return;
+                }
             }
             userId = mUserId;
         }