diff options
| -rw-r--r-- | src/gui/kernel/qevent.cpp | 6 | ||||
| -rw-r--r-- | src/gui/kernel/qwindowsysteminterface.cpp | 17 | ||||
| -rw-r--r-- | src/testlib/qtestcase.qdoc | 11 |
3 files changed, 33 insertions, 1 deletions
diff --git a/src/gui/kernel/qevent.cpp b/src/gui/kernel/qevent.cpp index 680acb16e7..5000cc35dd 100644 --- a/src/gui/kernel/qevent.cpp +++ b/src/gui/kernel/qevent.cpp @@ -1525,7 +1525,11 @@ QMoveEvent::~QMoveEvent() \ingroup events Expose events are sent to windows when an area of the window is invalidated - or window visibility in the windowing system changes. + or window exposure in the windowing system changes. + + A Window with a client area that is completely covered by another window, or + is otherwise not visible may be considered obscured by Qt and may in such + cases not receive expose events. The event handler QWindow::exposeEvent() receives expose events. */ diff --git a/src/gui/kernel/qwindowsysteminterface.cpp b/src/gui/kernel/qwindowsysteminterface.cpp index 233c27dee7..e2087bd22f 100644 --- a/src/gui/kernel/qwindowsysteminterface.cpp +++ b/src/gui/kernel/qwindowsysteminterface.cpp @@ -303,6 +303,23 @@ QWindowSystemInterfacePrivate::ExposeEvent::ExposeEvent(QWindow *window, const Q { } +/*! \internal + Handles an expose event. + + The platform plugin sends expose events when an area of the window + is invalidated or window exposure changes. \a region is in window + local coordinates. An empty region indicates that the window is + obscured, but note that the exposed property of the QWindow will be set + based on what QPlatformWindow::isExposed() returns at the time of this call, + not based on what the region is. // FIXME: this should probably be fixed. + + The platform plugin may omit sending expose events (or send obscure + events) for windows that are on screen but where the client area is + completely covered by other windows or otherwise not visible. Expose + event consumers can then use this to disable updates for such windows. + This is required behavior on platforms where OpenGL swapbuffers stops + blocking for obscured windows (like macOS). +*/ QT_DEFINE_QPA_EVENT_HANDLER(void, handleExposeEvent, QWindow *window, const QRegion ®ion) { QWindowSystemInterfacePrivate::ExposeEvent *e = diff --git a/src/testlib/qtestcase.qdoc b/src/testlib/qtestcase.qdoc index 1b1a8b6007..2d1e27ec40 100644 --- a/src/testlib/qtestcase.qdoc +++ b/src/testlib/qtestcase.qdoc @@ -1084,6 +1084,10 @@ This is mainly useful for asynchronous systems like X11, where a window will be mapped to screen some time after being asked to show itself on the screen. + Note that a window that is mapped to screen may still not be considered exposed if the window client + area is completely covered by other windows, or if the window is otherwise not visible. This function + will then time out when waiting for such a window. + \sa QTest::qWaitForWindowActive(), QWindow::isExposed() */ @@ -1106,6 +1110,13 @@ This is mainly useful for asynchronous systems like X11, where a window will be mapped to screen some time after being asked to show itself on the screen. + Note that a window that is mapped to screen may still not be considered exposed if the window client + area is completely covered by other windows, or if the window is otherwise not visible. This function + will then time out when waiting for such a window. + + A specific configuration where this happens is when using QGLWidget as a viewport widget on macOS: + The viewport widget gets the expose event, not the parent widget. + \sa QTest::qWaitForWindowActive() */ |