macOS: Fixed a bug when de-minimising an always on top NSView

modules/juce_gui_basics/native/juce_mac_NSViewComponentPeer.mm

@@ -158,7 +158,12 @@ public:
                                       object: window];
 
             [notificationCenter  addObserver: view
-                                    selector: @selector (frameChanged:)
+                                    selector: @selector (windowWillMiniaturize:)
+                                        name: NSWindowWillMiniaturizeNotification
+                                      object: window];
+
+            [notificationCenter  addObserver: view
+                                    selector: @selector (windowDidDeminiaturize:)
                                         name: NSWindowDidDeminiaturizeNotification
                                       object: window];
         }
@@ -472,10 +477,14 @@ public:
     bool setAlwaysOnTop (bool alwaysOnTop) override
     {
         if (! isSharedWindow)
+        {
             [window setLevel: alwaysOnTop ? ((getStyleFlags() & windowIsTemporary) != 0 ? NSPopUpMenuWindowLevel
                                                                                         : NSFloatingWindowLevel)
                                           : NSNormalWindowLevel];
 
+            isAlwaysOnTop = alwaysOnTop;
+        }
+
         return true;
     }
 
@@ -1394,6 +1403,7 @@ public:
     bool isZooming = false, isFirstLiveResize = false, textWasInserted = false;
     bool isStretchingTop = false, isStretchingLeft = false, isStretchingBottom = false, isStretchingRight = false;
     bool windowRepresentsFile = false;
+    bool isAlwaysOnTop = false, wasAlwaysOnTop = false;
     String stringBeingComposed;
     NSNotificationCenter* notificationCenter = nil;
 
@@ -1563,6 +1573,8 @@ struct JuceNSViewClass   : public ObjCClass<NSView>
         addMethod (@selector (magnifyWithEvent:),             magnify,                    "v@:@");
         addMethod (@selector (acceptsFirstMouse:),            acceptsFirstMouse,          "c@:@");
         addMethod (@selector (frameChanged:),                 frameChanged,               "v@:@");
+        addMethod (@selector (windowWillMiniaturize:),        windowWillMiniaturize,      "v@:@");
+        addMethod (@selector (windowDidDeminiaturize:),       windowDidDeminiaturize,     "v@:@");
         addMethod (@selector (wantsDefaultClipping:),         wantsDefaultClipping,       "c@:");
         addMethod (@selector (worksWhenModal),                worksWhenModal,             "c@:");
         addMethod (@selector (viewDidMoveToWindow),           viewDidMoveToWindow,        "v@:");
@@ -1658,6 +1670,32 @@ private:
     static void frameChanged (id self, SEL, NSNotification*)   { if (auto* p = getOwner (self)) p->redirectMovedOrResized(); }
     static void viewDidMoveToWindow (id self, SEL)             { if (auto* p = getOwner (self)) p->viewMovedToWindow(); }
 
+    static void windowWillMiniaturize (id self, SEL, NSNotification*)
+    {
+        if (auto* p = getOwner (self))
+        {
+            if (p->isAlwaysOnTop)
+            {
+                // there is a bug when restoring minimised always on top windows so we need
+                // to remove this behaviour before minimising and restore it afterwards
+                p->setAlwaysOnTop (false);
+                p->wasAlwaysOnTop = true;
+            }
+        }
+    }
+
+    static void windowDidDeminiaturize (id self, SEL, NSNotification*)
+    {
+        if (auto* p = getOwner (self))
+        {
+            if (p->wasAlwaysOnTop)
+            {
+                p->setAlwaysOnTop (true);
+                p->redirectMovedOrResized();
+            }
+        }
+    }
+
     static BOOL isOpaque (id self, SEL)
     {
         auto* owner = getOwner (self);