QPlatformCursor: Add functions for setting/clearing override cursors

QPA is modeled on the assumption that the cursor is a property
of the window and therefore sets the override cursors on all windows.
However, on macOS and Windows, the cursor is set per application (or
screen). On these platforms, the per window cursor setting needs
to be emulated which is a source of bugs especially for override
cursors.

Add new virtuals to QPlatformCursor allowing to set override
cursors which can be implemented by directly setting the cursor
on those platforms.

Task-number: QTBUG-40122
Task-number: QTBUG-61133
Change-Id: I31d6a927128d22bb1620a8ace35988c0e126236e
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@qt.io>
Reviewed-by: Maurice Kalinowski <maurice.kalinowski@qt.io>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/plugins/platforms/windows/qwindowsintegration.cpp b/src/plugins/platforms/windows/qwindowsintegration.cpp
index 6c8fccf350..eb7ad5ecd8 100644
--- a/src/plugins/platforms/windows/qwindowsintegration.cpp
+++ b/src/plugins/platforms/windows/qwindowsintegration.cpp
@@ -72,6 +72,7 @@
 #include <QtGui/private/qguiapplication_p.h>
 #include <QtGui/private/qhighdpiscaling_p.h>
 #include <QtGui/qpa/qplatforminputcontextfactory_p.h>
+#include <QtGui/qpa/qplatformcursor.h>
 
 #include <QtEventDispatcherSupport/private/qwindowsguieventdispatcher_p.h>
 
@@ -242,6 +243,7 @@ QWindowsIntegrationPrivate::QWindowsIntegrationPrivate(const QStringList &paramL
     }
 
     m_context.initTouch(m_options);
+    QPlatformCursor::setCapability(QPlatformCursor::OverrideCursor);
 }
 
 QWindowsIntegrationPrivate::~QWindowsIntegrationPrivate()