Send events when platform surfaces are created/about to be destroyed

These synchronously delivered events allow applications to correctly
and conveniently handle native platform surfaces being destroyed. This
is particularly useful when doing rendering on a non-gui thread as it
allows to shutdown rendering before the native surface gets destroyed
from under us.

Task-number: QTBUG-42476
Task-number: QTBUG-42483
Change-Id: I63f41bbdb32f281d0f3b8ec2537eb2b0361f3bb3
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/src/gui/kernel/qwindow.cpp b/src/gui/kernel/qwindow.cpp
index e23e0f8e57..a3b7f38c80 100644
--- a/src/gui/kernel/qwindow.cpp
+++ b/src/gui/kernel/qwindow.cpp
@@ -404,6 +404,11 @@ void QWindowPrivate::create(bool recursive)
                     window->d_func()->platformWindow->setParent(platformWindow);
             }
         }
+
+        if (platformWindow) {
+            QPlatformSurfaceEvent e(QPlatformSurfaceEvent::SurfaceCreated);
+            QGuiApplication::sendEvent(q, &e);
+        }
     }
 }
 
@@ -1590,6 +1595,10 @@ void QWindow::destroy()
     bool wasVisible = isVisible();
 
     setVisible(false);
+
+    QPlatformSurfaceEvent e(QPlatformSurfaceEvent::SurfaceAboutToBeDestroyed);
+    QGuiApplication::sendEvent(this, &e);
+
     delete d->platformWindow;
     d->resizeEventPending = true;
     d->receivedExpose = false;