commit ea3f4fc7e994c883c4a2022aa293625f7b60c682
author arthurhung <arthurhung@google.com> Mon Dec 21 23:18:53 2020 +0800
committer arthurhung <arthurhung@google.com> Tue Dec 29 13:42:33 2020 +0800
tree 86efb4c93f7138311ce79d66e5368c7c8cbba6c8
parent 57563a1020fefe9645e4d52a4a9d9ebdcab6d222

Prevent accidentally click on window with split touch

Currently, inputflinger would send an ACTION_POINTER_UP event with
AKEY_EVENT_FLAG_CANCELED when we have at least 2 pointers down and
one becomes the accidental touch.

An input window could have FLAG_SPLIT that could split a multi touch
event into some single touch events, so we should check the cancel flag
in order to prevent it trigger an accidental click on the target window.

Bug: 161655782
Test: inputflinger_tests
Test: enable twoshay, test accidental touch on slipt window.
Change-Id: I95eae0c9aef1f888f352b31affcece893d557754

services/inputflinger/dispatcher/InputDispatcher.cpp

diff --git a/services/inputflinger/dispatcher/InputDispatcher.cpp b/services/inputflinger/dispatcher/InputDispatcher.cpp
index 5832109..0122fb0 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.cpp
+++ b/services/inputflinger/dispatcher/InputDispatcher.cpp
@@ -3414,7 +3414,9 @@
                 // The first/last pointer went down/up.
                 action = maskedAction == AMOTION_EVENT_ACTION_POINTER_DOWN
                         ? AMOTION_EVENT_ACTION_DOWN
-                        : AMOTION_EVENT_ACTION_UP;
+                        : (originalMotionEntry.flags & AMOTION_EVENT_FLAG_CANCELED) != 0
+                                ? AMOTION_EVENT_ACTION_CANCEL
+                                : AMOTION_EVENT_ACTION_UP;
             } else {
                 // A secondary pointer went down/up.
                 uint32_t splitPointerIndex = 0;