2 files changed, 31 insertions, 26 deletions

diff --git a/src/plugins/platforms/cocoa/qcocoaintegration.mm b/src/plugins/platforms/cocoa/qcocoaintegration.mm
index 79f7ebda54..55b3805df3 100644
--- a/src/plugins/platforms/cocoa/qcocoaintegration.mm
+++ b/src/plugins/platforms/cocoa/qcocoaintegration.mm
@@ -70,12 +70,6 @@
 
 #include <IOKit/graphics/IOGraphicsLib.h>
 
-#if !QT_MACOS_PLATFORM_SDK_EQUAL_OR_ABOVE(__MAC_10_14)
-@interface NSApplication (MojaveForwardDeclarations)
-@property (strong) NSAppearance *appearance NS_AVAILABLE_MAC(10_14);
-@end
-#endif
-
 static void initResources()
 {
     Q_INIT_RESOURCE(qcocoaresources);
@@ -137,21 +131,6 @@ QCocoaIntegration::QCocoaIntegration(const QStringList &paramList)
     NSApplication *cocoaApplication = [QNSApplication sharedApplication];
     qt_redirectNSApplicationSendEvent();
 
-    if (__builtin_available(macOS 10.14, *)) {
-        // Disable dark appearance, unless the Info.plist or environment requests that it should be enabled
-        bool plistEnablesDarkAppearance = [[[NSBundle mainBundle] objectForInfoDictionaryKey:
-            @"NSRequiresAquaSystemAppearance"] boolValue];
-
-        bool hasEnvironmentRequiresAquaAppearance;
-        int environmentRequiresAquaAppearance = qEnvironmentVariableIntValue(
-            "QT_MAC_REQUIRES_AQUA_SYSTEM_APPEARANCE", &hasEnvironmentRequiresAquaAppearance);
-        bool environmentEnablesDarkAppearance = hasEnvironmentRequiresAquaAppearance
-            && environmentRequiresAquaAppearance == 0;
-
-        if (!(plistEnablesDarkAppearance || environmentEnablesDarkAppearance))
-            NSApp.appearance = [NSAppearance appearanceNamed:NSAppearanceNameAqua];
-    }
-
     if (qEnvironmentVariableIsEmpty("QT_MAC_DISABLE_FOREGROUND_APPLICATION_TRANSFORM")) {
         // Applications launched from plain executables (without an app
         // bundle) are "background" applications that does not take keybaord
diff --git a/src/plugins/styles/mac/qmacstyle_mac.mm b/src/plugins/styles/mac/qmacstyle_mac.mm
index 45da5fbd84..3405f01046 100644
--- a/src/plugins/styles/mac/qmacstyle_mac.mm
+++ b/src/plugins/styles/mac/qmacstyle_mac.mm
@@ -1880,20 +1880,46 @@ NSCell *QMacStylePrivate::cocoaCell(CocoaControl widget) const
     return cell;
 }
 
-void QMacStylePrivate::drawNSViewInRect(NSView *view, const QRectF &qtRect, QPainter *p,
+void QMacStylePrivate::drawNSViewInRect(NSView *view, const QRectF &rect, QPainter *p,
                                         __attribute__((noescape)) DrawRectBlock drawRectBlock) const
 {
     QMacCGContext ctx(p);
     setupNSGraphicsContext(ctx, YES);
 
-    const CGRect rect = qtRect.toCGRect();
+    // FIXME: The rect that we get in is relative to the widget that we're drawing
+    // style on behalf of, and doesn't take into account the offset of that widget
+    // to the widget that owns the backingstore, which we are placing the native
+    // view into below. This means most of the views are placed in the upper left
+    // corner of backingStoreNSView, which does not map to where the actual widget
+    // is, and which may cause problems such as triggering a setNeedsDisplay of the
+    // backingStoreNSView for the wrong rect. We work around this by making the view
+    // layer-backed, which prevents triggering display of the backingStoreNSView, but
+    // but there may be other issues lurking here due to the wrong position. QTBUG-68023
+    view.wantsLayer = YES;
+
+    // FIXME: We are also setting the frame of the incoming view a lot at the call
+    // sites of this function, making it unclear who's actually responsible for
+    // maintaining the size and position of the view. In theory the call sites
+    // should ensure the _size_ of the view is correct, and then let this code
+    // take care of _positioning_ the view at the right place inside backingStoreNSView.
+    // For now we pass on the rect as is, to prevent any regressions until this
+    // can be investigated properly.
+    view.frame = rect.toCGRect();
 
     [backingStoreNSView addSubview:view];
-    view.frame = rect;
+
+    // FIXME: Based on the code below, this method isn't drawing an NSView into
+    // a rect, it's drawing _part of the NSView_, defined by the incoming clip
+    // or dirty rect, into the current graphics context. We're doing some manual
+    // translations at the call sites that would indicate that this relationship
+    // is a bit fuzzy.
+    const CGRect dirtyRect = rect.toCGRect();
+
     if (drawRectBlock)
-        drawRectBlock(ctx, rect);
+        drawRectBlock(ctx, dirtyRect);
     else
-        [view drawRect:rect];
+        [view drawRect:dirtyRect];
+
     [view removeFromSuperviewWithoutNeedingDisplay];
 
     restoreNSGraphicsContext(ctx);