From ec6027f0c9b15cd23d7a7b52235b1e39413cf835 Mon Sep 17 00:00:00 2001 From: Elvis Lee Date: Wed, 17 Mar 2021 16:31:10 +0900 Subject: [PATCH 22/39] Connect flushRequest after forceRoundTrip If flushRequest is connected with aboutToBlock, the flushRequest may consumes all events so that processEvents might be blocked in forceRoundTrip. Change-Id: I12b2c506e8442bf0e75f6ab6e418d3e1eea6d68c Reviewed-by: Eskil Abrahamsen Blomfeldt (cherry picked from commit 654a54755138c520c3a41210d8078196e9a2c1bf) --- src/client/qwaylandintegration.cpp | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/src/client/qwaylandintegration.cpp b/src/client/qwaylandintegration.cpp index f5632982..3a6fa651 100644 --- a/src/client/qwaylandintegration.cpp +++ b/src/client/qwaylandintegration.cpp @@ -192,10 +192,6 @@ QAbstractEventDispatcher *QWaylandIntegration::createEventDispatcher() const void QWaylandIntegration::initialize() { - QAbstractEventDispatcher *dispatcher = QGuiApplicationPrivate::eventDispatcher; - QObject::connect(dispatcher, SIGNAL(aboutToBlock()), mDisplay.data(), SLOT(flushRequests())); - QObject::connect(dispatcher, SIGNAL(awake()), mDisplay.data(), SLOT(flushRequests())); - int fd = wl_display_get_fd(mDisplay->wl_display()); QSocketNotifier *sn = new QSocketNotifier(fd, QSocketNotifier::Read, mDisplay.data()); QObject::connect(sn, SIGNAL(activated(QSocketDescriptor)), mDisplay.data(), SLOT(flushRequests())); @@ -203,6 +199,13 @@ void QWaylandIntegration::initialize() // Call after eventDispatcher is fully connected, for QWaylandDisplay::forceRoundTrip() mDisplay->initialize(); + // But the aboutToBlock() and awake() should be connected after initializePlatform(). + // Otherwise the connected flushRequests() may consumes up all events before processEvents starts to wait, + // so that processEvents(QEventLoop::WaitForMoreEvents) may be blocked in the forceRoundTrip(). + QAbstractEventDispatcher *dispatcher = QGuiApplicationPrivate::eventDispatcher; + QObject::connect(dispatcher, SIGNAL(aboutToBlock()), mDisplay.data(), SLOT(flushRequests())); + QObject::connect(dispatcher, SIGNAL(awake()), mDisplay.data(), SLOT(flushRequests())); + // Qt does not support running with no screens mDisplay->ensureScreen(); } -- 2.36.1