Process focus events first
While refactoring ANR logic, we discovered that an existing Q behaviour
was broken by the focus refactoring. The behaviour aims to prevent keys
from being sent to incorrect windows.
The desired behaviour is as follows: if there are any unfinished events,
then do not process key events (keep them pending), which would allow
these key events to go to a new window, if one becomes focused. The
intent is that if the user hits "Alt+Tab" to switch to another window,
and starts typing right away, we want to make sure that we have
processed the focus event for the new window prior to determining where
to send the new key events after Alt+Tab.
The behaviour is broken today because we put the focus events at the
back of the queue. So even if we process the focus event first, it would
still go to the app after the key event, which would mean that the new
window may receive it, but would drop it because that window does not
yet have focus (since we haven't sent the focused event to it).
The proposed solution is to always put the focus events in the front of
the queue. But, we still need to preserve the relative order of focus
events. To account for that, we put a new focus event always at the
front of the queue, but behind any other focus events that may be there.
Bug: 143459140
Test: added in ANR CL because this behaviour is updated there.
Change-Id: I95256bd3f57988d1990cf1f21267c8f405892e8e
diff --git a/services/inputflinger/dispatcher/InputDispatcher.cpp b/services/inputflinger/dispatcher/InputDispatcher.cpp
index 6d8f036..d632cd7 100644
--- a/services/inputflinger/dispatcher/InputDispatcher.cpp
+++ b/services/inputflinger/dispatcher/InputDispatcher.cpp
@@ -632,6 +632,34 @@
}
}
+/**
+ * Return true if the events preceding this incoming motion event should be dropped
+ * Return false otherwise (the default behaviour)
+ */
+bool InputDispatcher::shouldPruneInboundQueueLocked(const MotionEntry& motionEntry) {
+ bool isPointerDownEvent = motionEntry.action == AMOTION_EVENT_ACTION_DOWN &&
+ (motionEntry.source & AINPUT_SOURCE_CLASS_POINTER);
+ if (isPointerDownEvent &&
+ mInputTargetWaitCause == INPUT_TARGET_WAIT_CAUSE_APPLICATION_NOT_READY &&
+ mInputTargetWaitApplicationToken != nullptr) {
+ int32_t displayId = motionEntry.displayId;
+ int32_t x = static_cast<int32_t>(
+ motionEntry.pointerCoords[0].getAxisValue(AMOTION_EVENT_AXIS_X));
+ int32_t y = static_cast<int32_t>(
+ motionEntry.pointerCoords[0].getAxisValue(AMOTION_EVENT_AXIS_Y));
+ sp<InputWindowHandle> touchedWindowHandle =
+ findTouchedWindowAtLocked(displayId, x, y, nullptr);
+ if (touchedWindowHandle != nullptr &&
+ touchedWindowHandle->getApplicationToken() != mInputTargetWaitApplicationToken) {
+ // User touched a different application than the one we are waiting on.
+ // Flag the event, and start pruning the input queue.
+ ALOGI("Pruning input queue because user touched a different application");
+ return true;
+ }
+ }
+ return false;
+}
+
bool InputDispatcher::enqueueInboundEventLocked(EventEntry* entry) {
bool needWake = mInboundQueue.empty();
mInboundQueue.push_back(entry);
@@ -665,32 +693,18 @@
// decides to touch a window in a different application.
// If the application takes too long to catch up then we drop all events preceding
// the touch into the other window.
- MotionEntry* motionEntry = static_cast<MotionEntry*>(entry);
- if (motionEntry->action == AMOTION_EVENT_ACTION_DOWN &&
- (motionEntry->source & AINPUT_SOURCE_CLASS_POINTER) &&
- mInputTargetWaitCause == INPUT_TARGET_WAIT_CAUSE_APPLICATION_NOT_READY &&
- mInputTargetWaitApplicationToken != nullptr) {
- int32_t displayId = motionEntry->displayId;
- int32_t x =
- int32_t(motionEntry->pointerCoords[0].getAxisValue(AMOTION_EVENT_AXIS_X));
- int32_t y =
- int32_t(motionEntry->pointerCoords[0].getAxisValue(AMOTION_EVENT_AXIS_Y));
- sp<InputWindowHandle> touchedWindowHandle =
- findTouchedWindowAtLocked(displayId, x, y, nullptr);
- if (touchedWindowHandle != nullptr &&
- touchedWindowHandle->getApplicationToken() !=
- mInputTargetWaitApplicationToken) {
- // User touched a different application than the one we are waiting on.
- // Flag the event, and start pruning the input queue.
- mNextUnblockedEvent = motionEntry;
- needWake = true;
- }
+ if (shouldPruneInboundQueueLocked(static_cast<MotionEntry&>(*entry))) {
+ mNextUnblockedEvent = entry;
+ needWake = true;
}
break;
}
- case EventEntry::Type::CONFIGURATION_CHANGED:
- case EventEntry::Type::DEVICE_RESET:
case EventEntry::Type::FOCUS: {
+ LOG_ALWAYS_FATAL("Focus events should be inserted using enqueueFocusEventLocked");
+ break;
+ }
+ case EventEntry::Type::CONFIGURATION_CHANGED:
+ case EventEntry::Type::DEVICE_RESET: {
// nothing to do
break;
}
@@ -985,9 +999,24 @@
}
void InputDispatcher::enqueueFocusEventLocked(const InputWindowHandle& window, bool hasFocus) {
+ if (mPendingEvent != nullptr) {
+ // Move the pending event to the front of the queue. This will give the chance
+ // for the pending event to get dispatched to the newly focused window
+ mInboundQueue.push_front(mPendingEvent);
+ mPendingEvent = nullptr;
+ }
+
FocusEntry* focusEntry =
new FocusEntry(mIdGenerator.nextId(), now(), window.getToken(), hasFocus);
- enqueueInboundEventLocked(focusEntry);
+
+ // This event should go to the front of the queue, but behind all other focus events
+ // Find the last focus event, and insert right after it
+ std::deque<EventEntry*>::reverse_iterator it =
+ std::find_if(mInboundQueue.rbegin(), mInboundQueue.rend(),
+ [](EventEntry* event) { return event->type == EventEntry::Type::FOCUS; });
+
+ // Maintain the order of focus events. Insert the entry after all other focus events.
+ mInboundQueue.insert(it.base(), focusEntry);
}
void InputDispatcher::dispatchFocusLocked(nsecs_t currentTime, FocusEntry* entry) {
@@ -2102,15 +2131,12 @@
const sp<InputWindowHandle>& windowHandle) {
if (applicationHandle != nullptr) {
if (windowHandle != nullptr) {
- std::string label(applicationHandle->getName());
- label += " - ";
- label += windowHandle->getName();
- return label;
+ return applicationHandle->getName() + " - " + windowHandle->getName();
} else {
return applicationHandle->getName();
}
} else if (windowHandle != nullptr) {
- return windowHandle->getName();
+ return windowHandle->getInfo()->applicationInfo.name + " - " + windowHandle->getName();
} else {
return "<unknown application or window>";
}
@@ -4619,7 +4645,7 @@
}
DispatchEntry* dispatchEntry = *dispatchEntryIt;
- nsecs_t eventDuration = finishTime - dispatchEntry->deliveryTime;
+ const nsecs_t eventDuration = finishTime - dispatchEntry->deliveryTime;
if (eventDuration > SLOW_EVENT_PROCESSING_WARNING_TIMEOUT) {
std::string msg =
StringPrintf("Window '%s' spent %0.1fms processing the last input event: ",
@@ -4643,7 +4669,7 @@
}
// Dequeue the event and start the next cycle.
- // Note that because the lock might have been released, it is possible that the
+ // Because the lock might have been released, it is possible that the
// contents of the wait queue to have been drained, so we need to double-check
// a few things.
dispatchEntryIt = connection->findWaitQueueEntry(seq);