Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 9d3d561b authored by Prabir Pradhan's avatar Prabir Pradhan
Browse files

InputDispatcher: Fix multi-display Pointer Capture 

There is an existing requirement that a window must both have focus and
be on the focused display to be able to gain Pointer Capture.

This means that focus changes on non-focused displays should not affect
Pointer Capture, and that a window must lose capture if its display
loses focus.

Verify these requirements with a test.

Bug: 342229227
Test: atest inputflinger_tests
Change-Id: I7b1c73b7759d8f20436ee401ba657a5dc8ead7a5
parent aa8e0640

services/inputflinger/dispatcher/InputDispatcher.cpp

+14 −10
Original line number Diff line number Diff line
@@ -5529,6 +5529,10 @@ void InputDispatcher::setFocusedDisplay(ui::LogicalDisplayId displayId) { 
            }

            mFocusedDisplayId = displayId;



            // Only a window on the focused display can have Pointer Capture, so disable the active

            // Pointer Capture session if there is one, since the focused display changed.

            disablePointerCaptureForcedLocked();



            // Find new focused window and validate

            sp<IBinder> newFocusedWindowToken = mFocusResolver.getFocusedWindowToken(displayId);

            sendFocusChangedCommandLocked(oldFocusedWindowToken, newFocusedWindowToken);
@@ -6929,17 +6933,17 @@ void InputDispatcher::onFocusChangedLocked( 
        enqueueFocusEventLocked(changes.newFocus, /*hasFocus=*/true, changes.reason);

    }



    // If a window has pointer capture, then it must have focus. We need to ensure that this

    // contract is upheld when pointer capture is being disabled due to a loss of window focus.

    // If the window loses focus before it loses pointer capture, then the window can be in a state

    // where it has pointer capture but not focus, violating the contract. Therefore we must

    // dispatch the pointer capture event before the focus event. Since focus events are added to

    // the front of the queue (above), we add the pointer capture event to the front of the queue

    // after the focus events are added. This ensures the pointer capture event ends up at the

    // front.

    if (mFocusedDisplayId == changes.displayId) {

        // If a window has pointer capture, then it must have focus and must be on the top-focused

        // display. We need to ensure that this contract is upheld when pointer capture is being

        // disabled due to a loss of window focus. If the window loses focus before it loses pointer

        // capture, then the window can be in a state where it has pointer capture but not focus,

        // violating the contract. Therefore we must dispatch the pointer capture event before the

        // focus event. Since focus events are added to the front of the queue (above), we add the

        // pointer capture event to the front of the queue after the focus events are added. This

        // ensures the pointer capture event ends up at the front.

        disablePointerCaptureForcedLocked();



    if (mFocusedDisplayId == changes.displayId) {

        sendFocusChangedCommandLocked(changes.oldFocus, changes.newFocus);

    }

}

services/inputflinger/tests/InputDispatcher_test.cpp

+31 −0
Original line number Diff line number Diff line
@@ -11054,6 +11054,37 @@ TEST_F(InputDispatcherPointerCaptureTests, MouseHoverAndPointerCapture) { 
    mWindow->assertNoEvents();

}













TEST_F(InputDispatcherPointerCaptureTests, MultiDisplayPointerCapture) {













    // The default display is the focused display to begin with.













    requestAndVerifyPointerCapture(mWindow, true);

























    // Move the second window to a second display, make it the focused window on that display.













    mSecondWindow->editInfo()->displayId = SECOND_DISPLAY_ID;













    mDispatcher->onWindowInfosChanged({{*mWindow->getInfo(), *mSecondWindow->getInfo()}, {}, 0, 0});













    setFocusedWindow(mSecondWindow);













    mSecondWindow->consumeFocusEvent(true);

























    mWindow->assertNoEvents();

























    // The second window cannot gain capture because it is not on the focused display.













    mDispatcher->requestPointerCapture(mSecondWindow->getToken(), true);













    mFakePolicy->assertSetPointerCaptureNotCalled();













    mSecondWindow->assertNoEvents();

























    // Make the second display the focused display.













    mDispatcher->setFocusedDisplay(SECOND_DISPLAY_ID);

























    // This causes the first window to lose pointer capture, and it's unable to request capture.













    mWindow->consumeCaptureEvent(false);













    mFakePolicy->assertSetPointerCaptureCalled(mWindow, false);

























    mDispatcher->requestPointerCapture(mWindow->getToken(), true);













    mFakePolicy->assertSetPointerCaptureNotCalled();

























    // The second window is now able to gain pointer capture successfully.













    requestAndVerifyPointerCapture(mSecondWindow, true);













}



























using InputDispatcherPointerCaptureDeathTest = InputDispatcherPointerCaptureTests;





























TEST_F(InputDispatcherPointerCaptureDeathTest,