Demobrowser: Fix black screen after exiting fullscreen mode on OS X.

When exiting fullscreen while viewing a full screen video, the video is
replaced with a black screen, and does not switch back to the initial
page.

This happens when hide() is called on a native window while being in
fullscreen, which hides the window, but does not exit full screen mode,
thus showing a black screen.

The workaround fix consists of two parts:
1) Make sure to delete the fullscreen window object, to release the
OS virtual screen it occupies (visible in mission control as a black
rectangle).
2) Hide and show the main page window, to force exit fullscreen mode.

Change-Id: I364d4427e84957ed97f57a14e2cfc2c95aed6f48
Task-number: QTBUG-52058
Reviewed-by: Kai Koehne <kai.koehne@theqtcompany.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/examples/webenginewidgets/demobrowser/tabwidget.cpp b/examples/webenginewidgets/demobrowser/tabwidget.cpp
index 73ca39bf9..3f859c386 100644
--- a/examples/webenginewidgets/demobrowser/tabwidget.cpp
+++ b/examples/webenginewidgets/demobrowser/tabwidget.cpp
@@ -392,9 +392,12 @@ void TabWidget::fullScreenRequested(QWebEngineFullScreenRequest request)
         WebView *oldWebView = this->webView(m_lineEdits->currentIndex());
         webPage->setView(oldWebView);
         request.accept();
-        raise();
-        m_fullScreenView->hide();
-        m_fullScreenNotification->hide();
+        // Change the delete and window hide/show back to a simple m_fullScreenView->hide()
+        // once QTBUG-46701 gets fixed.
+        delete m_fullScreenView;
+        m_fullScreenView = 0;
+        window()->hide();
+        window()->show();
     }
 }