macOS: Get rid of m_qtView member in QCocoaWindow that aliased m_view

The member was mirroring m_view in all cases except for foreign windows.
Instead of a member we now check window()->type() != Qt::ForeignWindow,
which is more explicit, especially for people not normally working on
the macOS platform.

To call methods that are only implemented for our QNSView subclass,
a new qnsview_cast() function has been introduced.

Change-Id: I0a2cfe1a5e4502250c17e1c3ebdce19e9ee5e572
Reviewed-by: Erik Verbruggen <erik.verbruggen@qt.io>

1 files changed, 3 insertions, 2 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoabackingstore.mm b/src/plugins/platforms/cocoa/qcocoabackingstore.mm
index af5418315c..a74995319b 100644
--- a/src/plugins/platforms/cocoa/qcocoabackingstore.mm
+++ b/src/plugins/platforms/cocoa/qcocoabackingstore.mm
@@ -40,6 +40,7 @@
 #include "qcocoabackingstore.h"
 
 #include "qcocoawindow.h"
+#include "qcocoahelpers.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -51,7 +52,7 @@ QCocoaBackingStore::QCocoaBackingStore(QWindow *window)
 QCocoaBackingStore::~QCocoaBackingStore()
 {
     if (QCocoaWindow *cocoaWindow = static_cast<QCocoaWindow *>(window()->handle()))
-        [cocoaWindow->m_qtView clearBackingStore:this];
+        [qnsview_cast(cocoaWindow->view()) clearBackingStore:this];
 }
 
 QImage::Format QCocoaBackingStore::format() const
@@ -68,7 +69,7 @@ void QCocoaBackingStore::flush(QWindow *window, const QRegion &region, const QPo
         return;
 
     if (QCocoaWindow *cocoaWindow = static_cast<QCocoaWindow *>(window->handle()))
-        [cocoaWindow->m_qtView flushBackingStore:this region:region offset:offset];
+        [qnsview_cast(cocoaWindow->view()) flushBackingStore:this region:region offset:offset];
 }
 
 QT_END_NAMESPACE