From cadc2c2c66568dc543bf5a6b0df0435b8089f6bb Mon Sep 17 00:00:00 2001
From: Taran Singh <tarandeep@google.com>
Date: Thu, 6 Jul 2023 22:42:34 +0000
Subject: [PATCH] Disable batching in InputEventReceiver for inking

Use unbatched events in IMF for lower latency.

Bug: 289864334
Bug: 287109569
Test: Manually using logcat & HandwritingIme

Change-Id: I11af096da743dadfa3361c236c224fceb7f7562b
---
 .../InputMethodService.java                   | 22 +++++++++++--------
 1 file changed, 13 insertions(+), 9 deletions(-)

diff --git a/core/java/android/inputmethodservice/InputMethodService.java b/core/java/android/inputmethodservice/InputMethodService.java
index a9c4818393a8f..e472a40617ee0 100644
--- a/core/java/android/inputmethodservice/InputMethodService.java
+++ b/core/java/android/inputmethodservice/InputMethodService.java
@@ -103,11 +103,10 @@ import android.util.PrintWriterPrinter;
 import android.util.Printer;
 import android.util.Xml;
 import android.util.proto.ProtoOutputStream;
-import android.view.BatchedInputEventReceiver.SimpleBatchedInputEventReceiver;
-import android.view.Choreographer;
 import android.view.Gravity;
 import android.view.InputChannel;
 import android.view.InputDevice;
+import android.view.InputEvent;
 import android.view.InputEventReceiver;
 import android.view.KeyCharacterMap;
 import android.view.KeyEvent;
@@ -1052,17 +1051,22 @@ public class InputMethodService extends AbstractInputMethodService {
             stylusEvents.forEach(InputMethodService.this::onStylusHandwritingMotionEvent);
 
             // create receiver for channel
-            mHandwritingEventReceiver = new SimpleBatchedInputEventReceiver(
-                    channel,
-                    Looper.getMainLooper(), Choreographer.getInstance(),
-                    event -> {
+            mHandwritingEventReceiver = new InputEventReceiver(channel, Looper.getMainLooper()) {
+                @Override
+                public void onInputEvent(InputEvent event) {
+                    boolean handled = false;
+                    try {
                         if (!(event instanceof MotionEvent)) {
-                            return false;
+                            return;
                         }
                         onStylusHandwritingMotionEvent((MotionEvent) event);
                         scheduleHandwritingSessionTimeout();
-                        return true;
-                    });
+                        handled = true;
+                    } finally {
+                        finishInputEvent(event, handled);
+                    }
+                }
+            };
             scheduleHandwritingSessionTimeout();
         }