2 files changed, 17 insertions, 13 deletions
diff --git a/src/plugins/platforms/cocoa/qcocoawindow.h b/src/plugins/platforms/cocoa/qcocoawindow.h
index 70b857d91e..750e3a0648 100644
--- a/src/plugins/platforms/cocoa/qcocoawindow.h
+++ b/src/plugins/platforms/cocoa/qcocoawindow.h
@@ -189,7 +189,7 @@ protected:
     void recreateWindowIfNeeded();
     QCocoaNSWindow *createNSWindow(bool shouldBePanel);
 
-    Qt::WindowState windowState() const;
+    Qt::WindowStates windowState() const;
     void applyWindowState(Qt::WindowStates newState);
     void toggleMaximized();
     void toggleFullScreen();
diff --git a/src/plugins/platforms/cocoa/qcocoawindow.mm b/src/plugins/platforms/cocoa/qcocoawindow.mm
index e3fbe8e2d9..c0eb7a9306 100644
--- a/src/plugins/platforms/cocoa/qcocoawindow.mm
+++ b/src/plugins/platforms/cocoa/qcocoawindow.mm
@@ -658,7 +658,7 @@ void QCocoaWindow::applyWindowState(Qt::WindowStates requestedState)
     if (!isContentView())
         return;
 
-    const Qt::WindowState currentState = windowState();
+    const Qt::WindowState currentState = QWindowPrivate::effectiveState(windowState());
     const Qt::WindowState newState = QWindowPrivate::effectiveState(requestedState);
 
     if (newState == currentState)
@@ -727,23 +727,27 @@ void QCocoaWindow::applyWindowState(Qt::WindowStates requestedState)
     }
 }
 
-Qt::WindowState QCocoaWindow::windowState() const
+Qt::WindowStates QCocoaWindow::windowState() const
 {
-    // FIXME: Support compound states (Qt::WindowStates)
-
+    Qt::WindowStates states = Qt::WindowNoState;
     NSWindow *window = m_view.window;
+
     if (window.miniaturized)
-        return Qt::WindowMinimized;
-    if (window.qt_fullScreen)
-        return Qt::WindowFullScreen;
-    if ((window.zoomed && !isTransitioningToFullScreen())
-        || (m_lastReportedWindowState == Qt::WindowMaximized && isTransitioningToFullScreen()))
-        return Qt::WindowMaximized;
+        states |= Qt::WindowMinimized;
+
+    // Full screen and maximized are mutually exclusive, as macOS
+    // will report a full screen window as zoomed.
+    if (window.qt_fullScreen) {
+        states |= Qt::WindowFullScreen;
+    } else if ((window.zoomed && !isTransitioningToFullScreen())
+        || (m_lastReportedWindowState == Qt::WindowMaximized && isTransitioningToFullScreen())) {
+        states |= Qt::WindowMaximized;
+    }
 
     // Note: We do not report Qt::WindowActive, even if isActive()
     // is true, as QtGui does not expect this window state to be set.
 
-    return Qt::WindowNoState;
+    return states;
 }
 
 void QCocoaWindow::toggleMaximized()
@@ -872,7 +876,7 @@ void QCocoaWindow::windowDidDeminiaturize()
 
 void QCocoaWindow::handleWindowStateChanged(HandleFlags flags)
 {
-    Qt::WindowState currentState = windowState();
+    Qt::WindowStates currentState = windowState();
     if (!(flags & HandleUnconditionally) && currentState == m_lastReportedWindowState)
         return;