macOS: Pick up QWizard background from keyboard assistant via NSBundle

As of macOS 10.14 the keyboard assistant background is shipped as part
of the compiled asset catalog of the app, so looking it up via a URL
will fail.

Instead we look it up via NSBundle's dedicated image lookup function,
which handles both cases.

The logic has also been moved to qwizard.cpp, since the additional
plumbing via QPlatformNativeInterface was unnecessary.

The keyboard assistant itself no longer shows the background image
as of macOS 12, so we might consider doing the same, but the design
of the assistant has also changed significantly, so as long as our
QWizard layout looks like the old keyboard assistant we keep the
background as well.

Pick-to: 6.5 6.2
Change-Id: I7d42dd79b285f3518837458864bca6bc353b3b6d
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>

1 files changed, 13 insertions, 18 deletions

diff --git a/src/widgets/dialogs/qwizard.cpp b/src/widgets/dialogs/qwizard.cpp
index cd41efa313..9d260cf4cf 100644
--- a/src/widgets/dialogs/qwizard.cpp
+++ b/src/widgets/dialogs/qwizard.cpp
@@ -29,9 +29,8 @@
 #include "qstyleoption.h"
 #include "qvarlengtharray.h"
 #if defined(Q_OS_MACOS)
-#include <QtCore/QMetaMethod>
-#include <QtGui/QGuiApplication>
-#include <qpa/qplatformnativeinterface.h>
+#include <AppKit/AppKit.h>
+#include <QtGui/private/qcoregraphics_p.h>
 #elif QT_CONFIG(style_windowsvista)
 #include "qwizard_win_p.h"
 #include "qtimer.h"
@@ -1705,23 +1704,19 @@ void QWizardPrivate::setStyle(QStyle *style)
 }
 
 #ifdef Q_OS_MACOS
-
 QPixmap QWizardPrivate::findDefaultBackgroundPixmap()
 {
-    QGuiApplication *app = qobject_cast<QGuiApplication *>(QCoreApplication::instance());
-    if (!app)
-        return QPixmap();
-    QPlatformNativeInterface *platformNativeInterface = app->platformNativeInterface();
-    int at = platformNativeInterface->metaObject()->indexOfMethod("defaultBackgroundPixmapForQWizard()");
-    if (at == -1)
-        return QPixmap();
-    QMetaMethod defaultBackgroundPixmapForQWizard = platformNativeInterface->metaObject()->method(at);
-    QPixmap result;
-    if (!defaultBackgroundPixmapForQWizard.invoke(platformNativeInterface, Q_RETURN_ARG(QPixmap, result)))
-        return QPixmap();
-    return result;
-}
+    auto *keyboardAssistantURL = [NSWorkspace.sharedWorkspace
+        URLForApplicationWithBundleIdentifier:@"com.apple.KeyboardSetupAssistant"];
+    auto *keyboardAssistantBundle = [NSBundle bundleWithURL:keyboardAssistantURL];
+    auto *assistantBackground = [keyboardAssistantBundle imageForResource:@"Background"];
+    auto size = QSizeF::fromCGSize(assistantBackground.size);
+    static const QSizeF expectedSize(242, 414);
+    if (size == expectedSize)
+        return qt_mac_toQPixmap(assistantBackground, size);
 
+    return QPixmap();
+}
 #endif
 
 #if QT_CONFIG(style_windowsvista)
@@ -2820,7 +2815,7 @@ void QWizard::setPixmap(WizardPixmap which, const QPixmap &pixmap)
     Returns the pixmap set for role \a which.
 
     By default, the only pixmap that is set is the BackgroundPixmap on
-    \macos version 10.13 and earlier.
+    \macos.
 
     \sa QWizardPage::pixmap(), {Elements of a Wizard Page}
 */