Process input events immediately when received.

Reduce the latency for handling input events by ensuring that they are
handled as soon as they are received from the dispatcher.  This also
makes it easier for the input system to intelligently batch motion events.

This is part of a series of changes to improve input system pipelining.

Bug: 5963420
Change-Id: I0b3f6cbb3de5ac3c4eed35dfc774d6bd4a0b07fc

1 files changed, 24 insertions, 15 deletions

diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index cbf4b5a..940d4c6 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -2631,7 +2631,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
             break;
         case DISPATCH_KEY: {
             KeyEvent event = (KeyEvent)msg.obj;
-            enqueueInputEvent(event, null, 0);
+            enqueueInputEvent(event, null, 0, true);
         } break;
         case DISPATCH_KEY_FROM_IME: {
             if (LOCAL_LOGV) Log.v(
@@ -2644,7 +2644,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
                 //noinspection UnusedAssignment
                 event = KeyEvent.changeFlags(event, event.getFlags() & ~KeyEvent.FLAG_FROM_SYSTEM);
             }
-            enqueueInputEvent(event, null, QueuedInputEvent.FLAG_DELIVER_POST_IME);
+            enqueueInputEvent(event, null, QueuedInputEvent.FLAG_DELIVER_POST_IME, true);
         } break;
         case FINISH_INPUT_CONNECTION: {
             InputMethodManager imm = InputMethodManager.peekInstance();
@@ -2947,7 +2947,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
             case MotionEvent.ACTION_DOWN:
                 x.reset(2);
                 y.reset(2);
-                dispatchKey(new KeyEvent(curTime, curTime,
+                enqueueInputEvent(new KeyEvent(curTime, curTime,
                         KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_DPAD_CENTER, 0, metaState,
                         KeyCharacterMap.VIRTUAL_KEYBOARD, 0, KeyEvent.FLAG_FALLBACK,
                         InputDevice.SOURCE_KEYBOARD));
@@ -2955,7 +2955,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
             case MotionEvent.ACTION_UP:
                 x.reset(2);
                 y.reset(2);
-                dispatchKey(new KeyEvent(curTime, curTime,
+                enqueueInputEvent(new KeyEvent(curTime, curTime,
                         KeyEvent.ACTION_UP, KeyEvent.KEYCODE_DPAD_CENTER, 0, metaState,
                         KeyCharacterMap.VIRTUAL_KEYBOARD, 0, KeyEvent.FLAG_FALLBACK,
                         InputDevice.SOURCE_KEYBOARD));
@@ -3009,7 +3009,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
                         + keycode);
                 movement--;
                 int repeatCount = accelMovement - movement;
-                dispatchKey(new KeyEvent(curTime, curTime,
+                enqueueInputEvent(new KeyEvent(curTime, curTime,
                         KeyEvent.ACTION_MULTIPLE, keycode, repeatCount, metaState,
                         KeyCharacterMap.VIRTUAL_KEYBOARD, 0, KeyEvent.FLAG_FALLBACK,
                         InputDevice.SOURCE_KEYBOARD));
@@ -3019,11 +3019,11 @@ public final class ViewRootImpl extends Handler implements ViewParent,
                         + keycode);
                 movement--;
                 curTime = SystemClock.uptimeMillis();
-                dispatchKey(new KeyEvent(curTime, curTime,
+                enqueueInputEvent(new KeyEvent(curTime, curTime,
                         KeyEvent.ACTION_DOWN, keycode, 0, metaState,
                         KeyCharacterMap.VIRTUAL_KEYBOARD, 0, KeyEvent.FLAG_FALLBACK,
                         InputDevice.SOURCE_KEYBOARD));
-                dispatchKey(new KeyEvent(curTime, curTime,
+                enqueueInputEvent(new KeyEvent(curTime, curTime,
                         KeyEvent.ACTION_UP, keycode, 0, metaState,
                         KeyCharacterMap.VIRTUAL_KEYBOARD, 0, KeyEvent.FLAG_FALLBACK,
                         InputDevice.SOURCE_KEYBOARD));
@@ -3090,7 +3090,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
 
         if (xDirection != mLastJoystickXDirection) {
             if (mLastJoystickXKeyCode != 0) {
-                dispatchKey(new KeyEvent(time, time,
+                enqueueInputEvent(new KeyEvent(time, time,
                         KeyEvent.ACTION_UP, mLastJoystickXKeyCode, 0, metaState,
                         deviceId, 0, KeyEvent.FLAG_FALLBACK, source));
                 mLastJoystickXKeyCode = 0;
@@ -3101,7 +3101,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
             if (xDirection != 0 && synthesizeNewKeys) {
                 mLastJoystickXKeyCode = xDirection > 0
                         ? KeyEvent.KEYCODE_DPAD_RIGHT : KeyEvent.KEYCODE_DPAD_LEFT;
-                dispatchKey(new KeyEvent(time, time,
+                enqueueInputEvent(new KeyEvent(time, time,
                         KeyEvent.ACTION_DOWN, mLastJoystickXKeyCode, 0, metaState,
                         deviceId, 0, KeyEvent.FLAG_FALLBACK, source));
             }
@@ -3109,7 +3109,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
 
         if (yDirection != mLastJoystickYDirection) {
             if (mLastJoystickYKeyCode != 0) {
-                dispatchKey(new KeyEvent(time, time,
+                enqueueInputEvent(new KeyEvent(time, time,
                         KeyEvent.ACTION_UP, mLastJoystickYKeyCode, 0, metaState,
                         deviceId, 0, KeyEvent.FLAG_FALLBACK, source));
                 mLastJoystickYKeyCode = 0;
@@ -3120,7 +3120,7 @@ public final class ViewRootImpl extends Handler implements ViewParent,
             if (yDirection != 0 && synthesizeNewKeys) {
                 mLastJoystickYKeyCode = yDirection > 0
                         ? KeyEvent.KEYCODE_DPAD_DOWN : KeyEvent.KEYCODE_DPAD_UP;
-                dispatchKey(new KeyEvent(time, time,
+                enqueueInputEvent(new KeyEvent(time, time,
                         KeyEvent.ACTION_DOWN, mLastJoystickYKeyCode, 0, metaState,
                         deviceId, 0, KeyEvent.FLAG_FALLBACK, source));
             }
@@ -3805,8 +3805,12 @@ public final class ViewRootImpl extends Handler implements ViewParent,
         }
     }
 
+    void enqueueInputEvent(InputEvent event) {
+        enqueueInputEvent(event, null, 0, false);
+    }
+
     void enqueueInputEvent(InputEvent event,
-            InputEventReceiver receiver, int flags) {
+            InputEventReceiver receiver, int flags, boolean processImmediately) {
         QueuedInputEvent q = obtainQueuedInputEvent(event, receiver, flags);
 
         if (ViewDebug.DEBUG_LATENCY) {
@@ -3830,7 +3834,11 @@ public final class ViewRootImpl extends Handler implements ViewParent,
             last.mNext = q;
         }
 
-        scheduleProcessInputEvents();
+        if (processImmediately) {
+            doProcessInputEvents();
+        } else {
+            scheduleProcessInputEvents();
+        }
     }
 
     private void scheduleProcessInputEvents() {
@@ -3919,13 +3927,14 @@ public final class ViewRootImpl extends Handler implements ViewParent,
 
         @Override
         public void onInputEvent(InputEvent event) {
-            enqueueInputEvent(event, this, 0);
+            enqueueInputEvent(event, this, 0, true);
         }
     }
     WindowInputEventReceiver mInputEventReceiver;
 
     public void dispatchKey(KeyEvent event) {
-        enqueueInputEvent(event, null, 0);
+        Message msg = obtainMessage(DISPATCH_KEY, event);
+        sendMessage(msg);
     }
 
     public void dispatchAppVisibility(boolean visible) {