Handle multiple windows in transferTouch
After the recent SPY window refactor, multiple windows could be getting
touch gesture at the same time.
When the 'transferTouch' API is invoked, inputdispatcher needs to find the best
window which to take touch from.
The logic used to be 'take the display which has exactly 1 touched
window, and then take that window'. This breaks when spy windows are in
use, because now both the 'regular' and the spy window would be getting
the same touch.
In this CL, we refine the logic for which window should be losing touch.
We would take the first foreground window that is being touched, on the
specific display.
We will also now explicitly ban split touch transfers. If touch is split
across multiple windows (excluding spy and wallpaper windows),
transferTouch will fail.
Bug: 220077253
Test: atest inputflinger_tests
Change-Id: I20a24b063dc0e0103a1692f85f99849544e7ec60
diff --git a/services/inputflinger/tests/InputDispatcher_test.cpp b/services/inputflinger/tests/InputDispatcher_test.cpp
index bf58705..7ac9ed9 100644
--- a/services/inputflinger/tests/InputDispatcher_test.cpp
+++ b/services/inputflinger/tests/InputDispatcher_test.cpp
@@ -2426,6 +2426,63 @@
secondWindow->consumeMotionUp();
}
+/**
+ * When 'transferTouch' API is invoked, dispatcher needs to find the "best" window to take touch
+ * from. When we have spy windows, there are several windows to choose from: either spy, or the
+ * 'real' (non-spy) window. Always prefer the 'real' window because that's what would be most
+ * natural to the user.
+ * In this test, we are sending a pointer to both spy window and first window. We then try to
+ * transfer touch to the second window. The dispatcher should identify the first window as the
+ * one that should lose the gesture, and therefore the action should be to move the gesture from
+ * the first window to the second.
+ * The main goal here is to test the behaviour of 'transferTouch' API, but it's still valid to test
+ * the other API, as well.
+ */
+TEST_P(TransferTouchFixture, TransferTouch_MultipleWindowsWithSpy) {
+ std::shared_ptr<FakeApplicationHandle> application = std::make_shared<FakeApplicationHandle>();
+
+ // Create a couple of windows + a spy window
+ sp<FakeWindowHandle> spyWindow =
+ new FakeWindowHandle(application, mDispatcher, "Spy", ADISPLAY_ID_DEFAULT);
+ spyWindow->setTrustedOverlay(true);
+ spyWindow->setSpy(true);
+ sp<FakeWindowHandle> firstWindow =
+ new FakeWindowHandle(application, mDispatcher, "First", ADISPLAY_ID_DEFAULT);
+ sp<FakeWindowHandle> secondWindow =
+ new FakeWindowHandle(application, mDispatcher, "Second", ADISPLAY_ID_DEFAULT);
+
+ // Add the windows to the dispatcher
+ mDispatcher->setInputWindows({{ADISPLAY_ID_DEFAULT, {spyWindow, firstWindow, secondWindow}}});
+
+ // Send down to the first window
+ NotifyMotionArgs downMotionArgs =
+ generateMotionArgs(AMOTION_EVENT_ACTION_DOWN, AINPUT_SOURCE_TOUCHSCREEN,
+ ADISPLAY_ID_DEFAULT);
+ mDispatcher->notifyMotion(&downMotionArgs);
+ // Only the first window and spy should get the down event
+ spyWindow->consumeMotionDown();
+ firstWindow->consumeMotionDown();
+
+ // Transfer touch to the second window. Non-spy window should be preferred over the spy window
+ // if f === 'transferTouch'.
+ TransferFunction f = GetParam();
+ const bool success = f(mDispatcher, firstWindow->getToken(), secondWindow->getToken());
+ ASSERT_TRUE(success);
+ // The first window gets cancel and the second gets down
+ firstWindow->consumeMotionCancel();
+ secondWindow->consumeMotionDown();
+
+ // Send up event to the second window
+ NotifyMotionArgs upMotionArgs =
+ generateMotionArgs(AMOTION_EVENT_ACTION_UP, AINPUT_SOURCE_TOUCHSCREEN,
+ ADISPLAY_ID_DEFAULT);
+ mDispatcher->notifyMotion(&upMotionArgs);
+ // The first window gets no events and the second+spy get up
+ firstWindow->assertNoEvents();
+ spyWindow->consumeMotionUp();
+ secondWindow->consumeMotionUp();
+}
+
TEST_P(TransferTouchFixture, TransferTouch_TwoPointersNonSplitTouch) {
std::shared_ptr<FakeApplicationHandle> application = std::make_shared<FakeApplicationHandle>();
@@ -2495,7 +2552,8 @@
::testing::Values(
[&](const std::unique_ptr<InputDispatcher>& dispatcher,
sp<IBinder> /*ignored*/, sp<IBinder> destChannelToken) {
- return dispatcher->transferTouch(destChannelToken);
+ return dispatcher->transferTouch(destChannelToken,
+ ADISPLAY_ID_DEFAULT);
},
[&](const std::unique_ptr<InputDispatcher>& dispatcher,
sp<IBinder> from, sp<IBinder> to) {
@@ -2603,7 +2661,8 @@
secondWindow->consumeMotionDown();
// Transfer touch focus to the second window
- const bool transferred = mDispatcher->transferTouch(secondWindow->getToken());
+ const bool transferred =
+ mDispatcher->transferTouch(secondWindow->getToken(), ADISPLAY_ID_DEFAULT);
// The 'transferTouch' call should not succeed, because there are 2 touched windows
ASSERT_FALSE(transferred);
firstWindow->assertNoEvents();
@@ -2727,7 +2786,7 @@
firstWindowInPrimary->consumeMotionDown(SECOND_DISPLAY_ID);
// Transfer touch focus
- ASSERT_TRUE(mDispatcher->transferTouch(secondWindowInSecondary->getToken()));
+ ASSERT_TRUE(mDispatcher->transferTouch(secondWindowInSecondary->getToken(), SECOND_DISPLAY_ID));
// The first window gets cancel.
firstWindowInPrimary->consumeMotionCancel(SECOND_DISPLAY_ID);