Merge branch 'master' into fixes/RightToLeftTextWrap

native/Avalonia.Native/inc/comimpl.h

@@ -8,8 +8,109 @@
 
 #include <cstring>
 
+/**
+ START_COM_CALL causes AddRef to be called at the beggining of a function.
+ When a function is exited, it causes ReleaseRef to be called.
+ This ensures that the object cannot be destroyed whilst the function is running.
+ For example: Window Show is called, which triggers an event, and user calls Close inside the event
+ causing the refcount to reach 0, and the object to be destroyed. Function then continues and this pointer
+ will now be invalid.
+ 
+ START_COM_CALL protects against this scenario.
+ */
+#define START_COM_CALL auto r = this->UnknownSelf()
+
 __IID_DEF(IUnknown, 0, 0, 0, C0, 00, 00, 00, 00, 00, 00, 46);
 
+template<class TInterface>
+class ComPtr
+{
+private:
+    TInterface* _obj;
+public:
+    ComPtr()
+    {
+        _obj = 0;
+    }
+    
+    ComPtr(TInterface* pObj)
+    {
+        _obj = 0;
+
+        if (pObj)
+        {
+            _obj = pObj;
+            _obj->AddRef();
+        }
+    }
+    
+    ComPtr(const ComPtr& ptr)
+    {
+        _obj = 0;
+        
+        if (ptr._obj)
+        {
+            _obj = ptr._obj;
+            _obj->AddRef();
+        }
+
+    }
+    
+    ComPtr& operator=(ComPtr other)
+    {
+        if(_obj != NULL)
+            _obj->Release();
+        _obj = other._obj;
+        if(_obj != NULL)
+            _obj->AddRef();
+        return *this;
+    }
+
+    ~ComPtr()
+    {
+        if (_obj)
+        {
+            _obj->Release();
+            _obj = 0;
+        }
+    }
+    
+    TInterface* getRaw()
+    {
+        return _obj;
+    }
+    
+    TInterface* getRetainedReference()
+    {
+        if(_obj == NULL)
+            return NULL;
+        _obj->AddRef();
+        return _obj;
+    }
+    
+    TInterface** getPPV()
+    {
+        return &_obj;
+    }
+    
+    operator TInterface*() const
+    {
+        return _obj;
+    }
+    TInterface& operator*() const
+    {
+        return *_obj;
+    }
+    TInterface** operator&()
+    {
+        return &_obj;
+    }
+    TInterface* operator->() const
+    {
+        return _obj;
+    }
+};
+
 class ComObject : public virtual IUnknown
 {
 private:
@@ -58,6 +159,12 @@ public:
         _refCount++;
         return S_OK;
     }
+    
+protected:
+   ComPtr<IUnknown> UnknownSelf()
+    {
+       return this;
+   }
 
 };
 
@@ -104,94 +211,5 @@ public:
     virtual ~ComSingleObject(){}
 };
 
-template<class TInterface>
-class ComPtr
-{
-private:
-    TInterface* _obj;
-public:
-    ComPtr()
-    {
-        _obj = 0;
-    }
-    
-    ComPtr(TInterface* pObj)
-    {
-        _obj = 0;
-
-        if (pObj)
-        {
-            _obj = pObj;
-            _obj->AddRef();
-        }
-    }
-    
-    ComPtr(const ComPtr& ptr)
-    {
-        _obj = 0;
-        
-        if (ptr._obj)
-        {
-            _obj = ptr._obj;
-            _obj->AddRef();
-        }
-
-    }
-    
-    ComPtr& operator=(ComPtr other)
-    {
-        if(_obj != NULL)
-            _obj->Release();
-        _obj = other._obj;
-        if(_obj != NULL)
-            _obj->AddRef();
-        return *this;
-    }
-
-    ~ComPtr()
-    {
-        if (_obj)
-        {
-            _obj->Release();
-            _obj = 0;
-        }
-    }
-    
-    TInterface* getRaw()
-    {
-        return _obj;
-    }
-    
-    TInterface* getRetainedReference()
-    {
-        if(_obj == NULL)
-            return NULL;
-        _obj->AddRef();
-        return _obj;
-    }
-    
-    TInterface** getPPV()
-    {
-        return &_obj;
-    }
-    
-    operator TInterface*() const
-    {
-        return _obj;
-    }
-    TInterface& operator*() const
-    {
-        return *_obj;
-    }
-    TInterface** operator&()
-    {
-        return &_obj;
-    }
-    TInterface* operator->() const
-    {
-        return _obj;
-    }
-};
-
 #endif // COMIMPL_H_INCLUDED
 #pragma clang diagnostic pop

native/Avalonia.Native/src/OSX/AvnString.mm

@@ -43,6 +43,8 @@ public:
     
     virtual HRESULT Pointer(void**retOut) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(retOut == nullptr)
@@ -58,14 +60,19 @@ public:
     
     virtual HRESULT Length(int*retOut) override
     {
-        if(retOut == nullptr)
+        START_COM_CALL;
+        
+        @autoreleasepool
         {
-            return E_POINTER;
+            if(retOut == nullptr)
+            {
+                return E_POINTER;
+            }
+            
+            *retOut = _length;
+            
+            return S_OK;
         }
-        
-        *retOut = _length;
-        
-        return S_OK;
     }
 };
 
@@ -109,10 +116,15 @@ public:
     
     virtual HRESULT Get(unsigned int index, IAvnString**ppv) override
     {
-        if(_list.size() <= index)
+        START_COM_CALL;
-            return E_INVALIDARG;
+        
-        *ppv = _list[index].getRetainedReference();
+        @autoreleasepool
-        return S_OK;
+        {
+            if(_list.size() <= index)
+                return E_INVALIDARG;
+            *ppv = _list[index].getRetainedReference();
+            return S_OK;
+        }
     }
 };
 

native/Avalonia.Native/src/OSX/Screens.mm

@@ -8,6 +8,8 @@ class Screens : public ComSingleObject<IAvnScreens, &IID_IAvnScreens>
 public:
     virtual HRESULT GetScreenCount (int* ret) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             *ret = (int)[NSScreen screens].count;
@@ -18,6 +20,8 @@ public:
     
     virtual HRESULT GetScreen (int index, AvnScreen* ret) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(index < 0 || index >= [NSScreen screens].count)

native/Avalonia.Native/src/OSX/cgl.mm

@@ -69,6 +69,8 @@ public:
     
     virtual HRESULT LegacyMakeCurrent() override
     {
+        START_COM_CALL;
+        
         if(CGLSetCurrentContext(Context) != 0)
             return E_FAIL;
         return S_OK;
@@ -76,6 +78,8 @@ public:
     
     virtual HRESULT MakeCurrent(IUnknown** ppv) override
     {
+        START_COM_CALL;
+        
         CGLContextObj saved = CGLGetCurrentContext();
         CGLLockContext(Context);
         if(CGLSetCurrentContext(Context) != 0)
@@ -128,6 +132,8 @@ public:
     
     virtual HRESULT CreateContext(IAvnGlContext* share, IAvnGlContext**ppv) override
     {
+        START_COM_CALL;
+        
         CGLContextObj shareContext = nil;
         if(share != nil)
         {
@@ -144,6 +150,8 @@ public:
     
     virtual HRESULT WrapContext(void* native, IAvnGlContext**ppv) override
     {
+        START_COM_CALL;
+        
         if(native == nil)
             return E_INVALIDARG;
         *ppv = new AvnGlContext((CGLContextObj) native);

native/Avalonia.Native/src/OSX/clipboard.mm

@@ -25,6 +25,8 @@ public:
    
     virtual HRESULT GetText (char* type, IAvnString**ppv) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(ppv == nullptr)
@@ -42,6 +44,8 @@ public:
     
     virtual HRESULT GetStrings(char* type, IAvnStringArray**ppv) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             *ppv= nil;
@@ -69,56 +73,71 @@ public:
     
     virtual HRESULT SetText (char* type, char* utf8String) override
     {
-        Clear();
+        START_COM_CALL;
+        
         @autoreleasepool
         {
+            Clear();
+            
             auto string = [NSString stringWithUTF8String:(const char*)utf8String];
             auto typeString = [NSString stringWithUTF8String:(const char*)type];
             if(_item == nil)
                 [_pb setString: string forType: typeString];
             else
                 [_item setString: string forType:typeString];
-        }
         
-        return S_OK;
+            return S_OK;
+        }
     }
     
     virtual HRESULT SetBytes(char* type, void* bytes, int len) override
     {
-        auto typeString = [NSString stringWithUTF8String:(const char*)type];
+        START_COM_CALL;
-        auto data = [NSData dataWithBytes:bytes length:len];
+        
-        if(_item == nil)
+        @autoreleasepool
-            [_pb setData:data forType:typeString];
+        {
-        else
+            auto typeString = [NSString stringWithUTF8String:(const char*)type];
-            [_item setData:data forType:typeString];
+            auto data = [NSData dataWithBytes:bytes length:len];
-        return S_OK;
+            if(_item == nil)
+                [_pb setData:data forType:typeString];
+            else
+                [_item setData:data forType:typeString];
+            return S_OK;
+        }
     }
        
     virtual HRESULT GetBytes(char* type, IAvnString**ppv) override
     {
-        *ppv = nil;
+        START_COM_CALL;
-        auto typeString = [NSString stringWithUTF8String:(const char*)type];
+        
-        NSData*data;
+        @autoreleasepool
-        @try
         {
-            if(_item)
+            *ppv = nil;
-                data = [_item dataForType:typeString];
+            auto typeString = [NSString stringWithUTF8String:(const char*)type];
-            else
+            NSData*data;
-                data = [_pb dataForType:typeString];
+            @try
-            if(data == nil)
+            {
+                if(_item)
+                    data = [_item dataForType:typeString];
+                else
+                    data = [_pb dataForType:typeString];
+                if(data == nil)
+                    return E_FAIL;
+            }
+            @catch(NSException* e)
+            {
                 return E_FAIL;
+            }
+            *ppv = CreateByteArray((void*)data.bytes, (int)data.length);
+            return S_OK;
         }
-        @catch(NSException* e)
-        {
-            return E_FAIL;
-        }
-        *ppv = CreateByteArray((void*)data.bytes, (int)data.length);
-        return S_OK;
     }
 
 
     virtual HRESULT Clear() override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(_item != nil)
@@ -128,15 +147,20 @@ public:
                 [_pb clearContents];
                 [_pb setString:@"" forType:NSPasteboardTypeString];
             }
-        }
         
-        return S_OK;
+            return S_OK;
+        }
     }
     
     virtual HRESULT ObtainFormats(IAvnStringArray** ppv) override
     {
-        *ppv = CreateAvnStringArray(_item == nil ? [_pb types] : [_item types]);
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = CreateAvnStringArray(_item == nil ? [_pb types] : [_item types]);
+            return S_OK;
+        }
     }
 };
 

native/Avalonia.Native/src/OSX/controlhost.mm

@@ -16,11 +16,16 @@ public:
     
     virtual HRESULT CreateDefaultChild(void* parent, void** retOut) override
     {
-        NSView* view = [NSView new];
+        START_COM_CALL;
-        [view setWantsLayer: true];
         
-        *retOut = (__bridge_retained void*)view;
+        @autoreleasepool
-        return S_OK;
+        {
+            NSView* view = [NSView new];
+            [view setWantsLayer: true];
+            
+            *retOut = (__bridge_retained void*)view;
+            return S_OK;
+        }
     };
     
     virtual IAvnNativeControlHostTopLevelAttachment* CreateAttachment() override
@@ -69,32 +74,42 @@ public:
     
     virtual HRESULT InitializeWithChildHandle(void* child) override
     {
-        if(_child != nil)
+        START_COM_CALL;
-            return E_FAIL;
+        
-        _child = (__bridge NSView*)child;
+        @autoreleasepool
-        if(_child == nil)
+        {
-            return E_FAIL;
+            if(_child != nil)
-        [_holder addSubview:_child];
+                return E_FAIL;
-        [_child setHidden: false];
+            _child = (__bridge NSView*)child;
-        return S_OK;
+            if(_child == nil)
+                return E_FAIL;
+            [_holder addSubview:_child];
+            [_child setHidden: false];
+            return S_OK;
+        }
     };
     
     virtual HRESULT AttachTo(IAvnNativeControlHost* host) override
     {
-        if(host == nil)
+        START_COM_CALL;
-        {
+        
-            [_holder removeFromSuperview];
+        @autoreleasepool
-            [_holder setHidden: true];
-        }
-        else
         {
-            AvnNativeControlHost* chost = dynamic_cast<AvnNativeControlHost*>(host);
+            if(host == nil)
-            if(chost == nil || chost->View == nil)
+            {
-                return E_FAIL;
+                [_holder removeFromSuperview];
-            [_holder setHidden:true];
+                [_holder setHidden: true];
-            [chost->View addSubview:_holder];
+            }
+            else
+            {
+                AvnNativeControlHost* chost = dynamic_cast<AvnNativeControlHost*>(host);
+                if(chost == nil || chost->View == nil)
+                    return E_FAIL;
+                [_holder setHidden:true];
+                [chost->View addSubview:_holder];
+            }
+            return S_OK;
         }
-        return S_OK;
     };
     
     virtual void ShowInBounds(float x, float y, float width, float height) override

native/Avalonia.Native/src/OSX/cursor.mm

@@ -53,36 +53,46 @@ public:
     
     virtual HRESULT GetCursor (AvnStandardCursorType cursorType, IAvnCursor** retOut) override
     {
-        *retOut = s_cursorMap[cursorType];
+        START_COM_CALL;
         
-        if(*retOut != nullptr)
+        @autoreleasepool
         {
-            (*retOut)->AddRef();
+            *retOut = s_cursorMap[cursorType];
-        }
             
-        return S_OK;
+            if(*retOut != nullptr)
+            {
+                (*retOut)->AddRef();
+            }
+                
+            return S_OK;
+        }
     }
     
     virtual HRESULT CreateCustomCursor (void* bitmapData, size_t length, AvnPixelSize hotPixel, IAvnCursor** retOut) override
     {
-        if(bitmapData == nullptr || retOut == nullptr)
+        START_COM_CALL;
+        
+        @autoreleasepool
         {
-            return E_POINTER;
+            if(bitmapData == nullptr || retOut == nullptr)
+            {
+                return E_POINTER;
+            }
+            
+            NSData *imageData = [NSData dataWithBytes:bitmapData length:length];
+            NSImage *image = [[NSImage alloc] initWithData:imageData];
+            
+            
+            NSPoint hotSpot;
+            hotSpot.x = hotPixel.Width;
+            hotSpot.y = hotPixel.Height;
+            
+            *retOut = new Cursor([[NSCursor new] initWithImage: image hotSpot: hotSpot]);
+            
+            (*retOut)->AddRef();
+            
+            return S_OK;
         }
-        
-        NSData *imageData = [NSData dataWithBytes:bitmapData length:length];
-        NSImage *image = [[NSImage alloc] initWithData:imageData];
-        
-        
-        NSPoint hotSpot;
-        hotSpot.x = hotPixel.Width;
-        hotSpot.y = hotPixel.Height;
-        
-        *retOut = new Cursor([[NSCursor new] initWithImage: image hotSpot: hotSpot]);
-        
-        (*retOut)->AddRef();
-        
-        return S_OK;
     }
 };
 

native/Avalonia.Native/src/OSX/main.mm

@@ -107,27 +107,42 @@ public:
     
     virtual HRESULT SetApplicationTitle(char* utf8String) override
     {
-        auto appTitle = [NSString stringWithUTF8String: utf8String];
+        START_COM_CALL;
         
-        [[NSProcessInfo processInfo] setProcessName:appTitle];
+        @autoreleasepool
-        
+        {
-        
+            auto appTitle = [NSString stringWithUTF8String: utf8String];
-        SetProcessName(appTitle);
+            
-        
+            [[NSProcessInfo processInfo] setProcessName:appTitle];
-        return S_OK;
+            
+            
+            SetProcessName(appTitle);
+            
+            return S_OK;
+        }
     }
     
     virtual HRESULT SetShowInDock(int show)  override
     {
-        AvnDesiredActivationPolicy = show
+        START_COM_CALL;
-            ? NSApplicationActivationPolicyRegular : NSApplicationActivationPolicyAccessory;
+        
-        return S_OK;
+        @autoreleasepool
+        {
+            AvnDesiredActivationPolicy = show
+                ? NSApplicationActivationPolicyRegular : NSApplicationActivationPolicyAccessory;
+            return S_OK;
+        }
     }
     
     virtual HRESULT SetDisableDefaultApplicationMenuItems (bool enabled) override
     {
-        SetAutoGenerateDefaultAppMenuItems(!enabled);
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            SetAutoGenerateDefaultAppMenuItems(!enabled);
+            return S_OK;
+        }
     }
 };
 
@@ -165,6 +180,8 @@ public:
     FORWARD_IUNKNOWN()
     virtual HRESULT Initialize(IAvnGCHandleDeallocatorCallback* deallocator, IAvnApplicationEvents* events) override
     {
+        START_COM_CALL;
+        
         _deallocator = deallocator;
         @autoreleasepool{
             [[ThreadingInitializer new] do];
@@ -180,89 +197,154 @@ public:
     
     virtual HRESULT CreateWindow(IAvnWindowEvents* cb, IAvnGlContext* gl, IAvnWindow** ppv)  override
     {
-        if(cb == nullptr || ppv == nullptr)
+        START_COM_CALL;
-            return E_POINTER;
+        
-        *ppv = CreateAvnWindow(cb, gl);
+        @autoreleasepool
-        return S_OK;
+        {
+            if(cb == nullptr || ppv == nullptr)
+                return E_POINTER;
+            *ppv = CreateAvnWindow(cb, gl);
+            return S_OK;
+        }
     };
     
     virtual HRESULT CreatePopup(IAvnWindowEvents* cb, IAvnGlContext* gl, IAvnPopup** ppv) override
     {
-        if(cb == nullptr || ppv == nullptr)
+        START_COM_CALL;
-            return E_POINTER;
         
-        *ppv = CreateAvnPopup(cb, gl);
+        @autoreleasepool
-        return S_OK;
+        {
+            if(cb == nullptr || ppv == nullptr)
+                return E_POINTER;
+            
+            *ppv = CreateAvnPopup(cb, gl);
+            return S_OK;
+        }
     }
     
     virtual HRESULT CreatePlatformThreadingInterface(IAvnPlatformThreadingInterface** ppv)  override
     {
-        *ppv = CreatePlatformThreading();
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = CreatePlatformThreading();
+            return S_OK;
+        }
     }
     
     virtual HRESULT CreateSystemDialogs(IAvnSystemDialogs** ppv) override
     {
-        *ppv = ::CreateSystemDialogs();
+        START_COM_CALL;
-        return  S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreateSystemDialogs();
+            return  S_OK;
+        }
     }
     
     virtual HRESULT CreateScreens (IAvnScreens** ppv) override
     {
-        *ppv = ::CreateScreens ();
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreateScreens ();
+            return S_OK;
+        }
     }
 
     virtual HRESULT CreateClipboard(IAvnClipboard** ppv) override
     {
-        *ppv = ::CreateClipboard (nil, nil);
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreateClipboard (nil, nil);
+            return S_OK;
+        }
     }
     
     virtual HRESULT CreateDndClipboard(IAvnClipboard** ppv) override
     {
-        *ppv = ::CreateClipboard (nil, [NSPasteboardItem new]);
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreateClipboard (nil, [NSPasteboardItem new]);
+            return S_OK;
+        }
     }
 
     virtual HRESULT CreateCursorFactory(IAvnCursorFactory** ppv) override
     {
-        *ppv = ::CreateCursorFactory();
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreateCursorFactory();
+            return S_OK;
+        }
     }
     
     virtual HRESULT ObtainGlDisplay(IAvnGlDisplay** ppv) override
     {
-        auto rv = ::GetGlDisplay();
+        START_COM_CALL;
-        if(rv == NULL)
+        
-            return E_FAIL;
+        @autoreleasepool
-        rv->AddRef();
+        {
-        *ppv = rv;
+            auto rv = ::GetGlDisplay();
-        return S_OK;
+            if(rv == NULL)
+                return E_FAIL;
+            rv->AddRef();
+            *ppv = rv;
+            return S_OK;
+        }
     }
     
     virtual HRESULT CreateMenu (IAvnMenuEvents* cb, IAvnMenu** ppv) override
     {
-        *ppv = ::CreateAppMenu(cb);
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreateAppMenu(cb);
+            return S_OK;
+        }
     }
     
     virtual HRESULT CreateMenuItem (IAvnMenuItem** ppv) override
     {
-        *ppv = ::CreateAppMenuItem();
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreateAppMenuItem();
+            return S_OK;
+        }
     }
     
     virtual HRESULT CreateMenuItemSeparator (IAvnMenuItem** ppv) override
     {
-        *ppv = ::CreateAppMenuItemSeparator();
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            *ppv = ::CreateAppMenuItemSeparator();
+            return S_OK;
+        }
     }
     
     virtual HRESULT SetAppMenu (IAvnMenu* appMenu) override
     {
-        ::SetAppMenu(s_appTitle, appMenu);
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            ::SetAppMenu(s_appTitle, appMenu);
+            return S_OK;
+        }
     }
 };
 

native/Avalonia.Native/src/OSX/menu.mm

@@ -95,6 +95,8 @@ NSMenuItem* AvnAppMenuItem::GetNative()
 
 HRESULT AvnAppMenuItem::SetSubMenu (IAvnMenu* menu)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         if(menu != nullptr)
@@ -114,6 +116,8 @@ HRESULT AvnAppMenuItem::SetSubMenu (IAvnMenu* menu)
 
 HRESULT AvnAppMenuItem::SetTitle (char* utf8String)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         if (utf8String != nullptr)
@@ -128,6 +132,8 @@ HRESULT AvnAppMenuItem::SetTitle (char* utf8String)
 
 HRESULT AvnAppMenuItem::SetGesture (AvnKey key, AvnInputModifiers modifiers)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         if(key != AvnKeyNone)
@@ -183,6 +189,8 @@ HRESULT AvnAppMenuItem::SetGesture (AvnKey key, AvnInputModifiers modifiers)
 
 HRESULT AvnAppMenuItem::SetAction (IAvnPredicateCallback* predicate, IAvnActionCallback* callback)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         _predicate = predicate;
@@ -193,6 +201,8 @@ HRESULT AvnAppMenuItem::SetAction (IAvnPredicateCallback* predicate, IAvnActionC
 
 HRESULT AvnAppMenuItem::SetIsChecked (bool isChecked)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         [_native setState:(isChecked && _isCheckable ? NSOnState : NSOffState)];
@@ -202,6 +212,8 @@ HRESULT AvnAppMenuItem::SetIsChecked (bool isChecked)
 
 HRESULT AvnAppMenuItem::SetToggleType(AvnMenuItemToggleType toggleType)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         switch(toggleType)
@@ -231,6 +243,8 @@ HRESULT AvnAppMenuItem::SetToggleType(AvnMenuItemToggleType toggleType)
 
 HRESULT AvnAppMenuItem::SetIcon(void *data, size_t length)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         if(data != nullptr)
@@ -317,6 +331,8 @@ void AvnAppMenu::RaiseClosed()
 
 HRESULT AvnAppMenu::InsertItem(int index, IAvnMenuItem *item)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         if([_native hasGlobalMenuItem])
@@ -337,6 +353,8 @@ HRESULT AvnAppMenu::InsertItem(int index, IAvnMenuItem *item)
 
 HRESULT AvnAppMenu::RemoveItem (IAvnMenuItem* item)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         auto avnMenuItem = dynamic_cast<AvnAppMenuItem*>(item);
@@ -352,6 +370,8 @@ HRESULT AvnAppMenu::RemoveItem (IAvnMenuItem* item)
 
 HRESULT AvnAppMenu::SetTitle (char* utf8String)
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         if (utf8String != nullptr)
@@ -365,6 +385,8 @@ HRESULT AvnAppMenu::SetTitle (char* utf8String)
 
 HRESULT AvnAppMenu::Clear()
 {
+    START_COM_CALL;
+    
     @autoreleasepool
     {
         [_native removeAllItems];

native/Avalonia.Native/src/OSX/platformthreading.mm

@@ -114,6 +114,8 @@ public:
     
     virtual HRESULT RunLoop(IAvnLoopCancellation* cancel) override
     {
+        START_COM_CALL;
+        
         auto can = dynamic_cast<LoopCancellation*>(cancel);
         if(can->Cancelled)
             return S_OK;

native/Avalonia.Native/src/OSX/rendertarget.mm

@@ -247,6 +247,8 @@ public:
     
     virtual HRESULT GetPixelSize(AvnPixelSize* ret)  override
     {
+        START_COM_CALL;
+        
         if(!_surface)
             return E_FAIL;
         *ret = _surface->size;
@@ -255,6 +257,8 @@ public:
     
     virtual HRESULT GetScaling(double* ret)  override
     {
+        START_COM_CALL;
+        
         if(!_surface)
             return E_FAIL;
         *ret = _surface->scale;
@@ -281,6 +285,8 @@ public:
     
     virtual HRESULT BeginDrawing(IAvnGlSurfaceRenderingSession** ret)  override
     {
+        START_COM_CALL;
+        
         ComPtr<IUnknown> releaseContext;
         @synchronized (_target->lock) {
             if(_target->surface == nil)

native/Avalonia.Native/src/OSX/window.mm

@@ -54,6 +54,8 @@ public:
     
     virtual HRESULT ObtainNSWindowHandle(void** ret) override
     {
+        START_COM_CALL;
+        
         if (ret == nullptr)
         {
             return E_POINTER;
@@ -66,6 +68,8 @@ public:
     
     virtual HRESULT ObtainNSWindowHandleRetained(void** ret) override
     {
+        START_COM_CALL;
+        
         if (ret == nullptr)
         {
             return E_POINTER;
@@ -78,6 +82,8 @@ public:
     
     virtual HRESULT ObtainNSViewHandle(void** ret) override
     {
+        START_COM_CALL;
+        
         if (ret == nullptr)
         {
             return E_POINTER;
@@ -90,6 +96,8 @@ public:
     
     virtual HRESULT ObtainNSViewHandleRetained(void** ret) override
     {
+        START_COM_CALL;
+        
         if (ret == nullptr)
         {
             return E_POINTER;
@@ -107,23 +115,27 @@ public:
     
     virtual HRESULT Show(bool activate) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             SetPosition(lastPositionSet);
             UpdateStyle();
             
             [Window setContentView: StandardContainer];
+            [Window setTitle:_lastTitle];
             
             if(ShouldTakeFocusOnShow() && activate)
             {
+                [Window orderFront: Window];
                 [Window makeKeyAndOrderFront:Window];
+                [Window makeFirstResponder:View];
                 [NSApp activateIgnoringOtherApps:YES];
             }
             else
             {
                 [Window orderFront: Window];
             }
-            [Window setTitle:_lastTitle];
             
             _shown = true;
             
@@ -138,6 +150,8 @@ public:
     
     virtual HRESULT Hide () override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(Window != nullptr)
@@ -152,6 +166,8 @@ public:
     
     virtual HRESULT Activate () override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(Window != nullptr)
@@ -166,6 +182,8 @@ public:
     
     virtual HRESULT SetTopMost (bool value) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             [Window setLevel: value ? NSFloatingWindowLevel : NSNormalWindowLevel];
@@ -176,11 +194,16 @@ public:
     
     virtual HRESULT Close() override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if (Window != nullptr)
             {
-                [Window close];
+                auto window = Window;
+                Window = nullptr;
+                
+                [window close];
             }
             
             return S_OK;
@@ -189,6 +212,8 @@ public:
     
     virtual HRESULT GetClientSize(AvnSize* ret) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(ret == nullptr)
@@ -219,6 +244,8 @@ public:
     
     virtual HRESULT GetScaling (double* ret) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(ret == nullptr)
@@ -237,6 +264,8 @@ public:
     
     virtual HRESULT SetMinMaxSize (AvnSize minSize, AvnSize maxSize) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             [Window setMinSize: ToNSSize(minSize)];
@@ -248,6 +277,8 @@ public:
     
     virtual HRESULT Resize(double x, double y) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             auto maxSize = [Window maxSize];
@@ -287,6 +318,8 @@ public:
     
     virtual HRESULT Invalidate (AvnRect rect) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             [View setNeedsDisplayInRect:[View frame]];
@@ -297,6 +330,8 @@ public:
     
     virtual HRESULT SetMainMenu(IAvnMenu* menu) override
     {
+        START_COM_CALL;
+        
         _mainMenu = menu;
         
         auto nativeMenu = dynamic_cast<AvnAppMenu*>(menu);
@@ -315,6 +350,8 @@ public:
     
     virtual HRESULT BeginMoveDrag () override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             auto lastEvent = [View lastMouseDownEvent];
@@ -332,11 +369,15 @@ public:
     
     virtual HRESULT BeginResizeDrag (AvnWindowEdge edge) override
     {
+        START_COM_CALL;
+        
         return S_OK;
     }
     
     virtual HRESULT GetPosition (AvnPoint* ret) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(ret == nullptr)
@@ -357,6 +398,8 @@ public:
     
     virtual HRESULT SetPosition (AvnPoint point) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             lastPositionSet = point;
@@ -368,6 +411,8 @@ public:
     
     virtual HRESULT PointToClient (AvnPoint point, AvnPoint* ret) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(ret == nullptr)
@@ -386,6 +431,8 @@ public:
     
     virtual HRESULT PointToScreen (AvnPoint point, AvnPoint* ret) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(ret == nullptr)
@@ -403,12 +450,16 @@ public:
     
     virtual HRESULT ThreadSafeSetSwRenderedFrame(AvnFramebuffer* fb, IUnknown* dispose) override
     {
+        START_COM_CALL;
+        
         [View setSwRenderedFrame: fb dispose: dispose];
         return S_OK;
     }
     
     virtual HRESULT SetCursor(IAvnCursor* cursor) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             Cursor* avnCursor = dynamic_cast<Cursor*>(cursor);
@@ -438,6 +489,8 @@ public:
     
     virtual HRESULT CreateGlRenderTarget(IAvnGlSurfaceRenderTarget** ppv) override
     {
+        START_COM_CALL;
+        
         if(View == NULL)
             return E_FAIL;
         *ppv = [renderTarget createSurfaceRenderTarget];
@@ -446,6 +499,8 @@ public:
     
     virtual HRESULT CreateNativeControlHost(IAvnNativeControlHost** retOut) override
     {
+        START_COM_CALL;
+        
         if(View == NULL)
             return E_FAIL;
         *retOut = ::CreateNativeControlHost(View);
@@ -454,6 +509,8 @@ public:
     
     virtual HRESULT SetBlurEnabled (bool enable) override
     {
+        START_COM_CALL;
+        
         [StandardContainer ShowBlur:enable];
         
         return S_OK;
@@ -463,6 +520,8 @@ public:
                                               IAvnClipboard* clipboard, IAvnDndResultCallback* cb,
                                               void* sourceHandle) override
     {
+        START_COM_CALL;
+        
         auto item = TryGetPasteboardItem(clipboard);
         [item setString:@"" forType:GetAvnCustomDataType()];
         if(item == nil)
@@ -564,6 +623,11 @@ private:
     
     void HideOrShowTrafficLights ()
     {
+        if (Window == nil)
+        {
+            return;
+        }
+        
         for (id subview in Window.contentView.superview.subviews) {
             if ([subview isKindOfClass:NSClassFromString(@"NSTitlebarContainerView")]) {
                 NSView *titlebarView = [subview subviews][0];
@@ -590,8 +654,10 @@ private:
     
     virtual HRESULT Show (bool activate) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
-        {            
+        {
             WindowBaseImpl::Show(activate);
             
             HideOrShowTrafficLights();
@@ -602,6 +668,8 @@ private:
     
     virtual HRESULT SetEnabled (bool enable) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             [Window setEnabled:enable];
@@ -611,6 +679,8 @@ private:
     
     virtual HRESULT SetParent (IAvnWindow* parent) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(parent == nullptr)
@@ -722,6 +792,8 @@ private:
     
     virtual HRESULT SetCanResize(bool value) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             _canResize = value;
@@ -732,6 +804,8 @@ private:
     
     virtual HRESULT SetDecorations(SystemDecorations value) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             auto currentWindowState = _lastWindowState;
@@ -797,6 +871,8 @@ private:
     
     virtual HRESULT SetTitle (char* utf8title) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             _lastTitle = [NSString stringWithUTF8String:(const char*)utf8title];
@@ -808,6 +884,8 @@ private:
     
     virtual HRESULT SetTitleBarColor(AvnColor color) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             float a = (float)color.Alpha / 255.0f;
@@ -837,6 +915,8 @@ private:
     
     virtual HRESULT GetWindowState (AvnWindowState*ret) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
             if(ret == nullptr)
@@ -870,86 +950,111 @@ private:
     
     virtual HRESULT TakeFocusFromChildren () override
     {
-        if(Window == nil)
+        START_COM_CALL;
-            return S_OK;
-        if([Window isKeyWindow])
-            [Window makeFirstResponder: View];
         
-        return S_OK;
+        @autoreleasepool
+        {
+            if(Window == nil)
+                return S_OK;
+            if([Window isKeyWindow])
+                [Window makeFirstResponder: View];
+            
+            return S_OK;
+        }
     }
     
     virtual HRESULT SetExtendClientArea (bool enable) override
     {
-        _isClientAreaExtended = enable;
+        START_COM_CALL;
         
-        if(enable)
+        @autoreleasepool
         {
-            Window.titleVisibility = NSWindowTitleHidden;
+            _isClientAreaExtended = enable;
-            
-            [Window setTitlebarAppearsTransparent:true];
-            
-            auto wantsTitleBar = (_extendClientHints & AvnSystemChrome) || (_extendClientHints & AvnPreferSystemChrome);
-            
-            if (wantsTitleBar)
-            {
-                [StandardContainer ShowTitleBar:true];
-            }
-            else
-            {
-                [StandardContainer ShowTitleBar:false];
-            }
             
-            if(_extendClientHints & AvnOSXThickTitleBar)
+            if(enable)
             {
-                Window.toolbar = [NSToolbar new];
+                Window.titleVisibility = NSWindowTitleHidden;
-                Window.toolbar.showsBaselineSeparator = false;
+                
+                [Window setTitlebarAppearsTransparent:true];
+                
+                auto wantsTitleBar = (_extendClientHints & AvnSystemChrome) || (_extendClientHints & AvnPreferSystemChrome);
+                
+                if (wantsTitleBar)
+                {
+                    [StandardContainer ShowTitleBar:true];
+                }
+                else
+                {
+                    [StandardContainer ShowTitleBar:false];
+                }
+                
+                if(_extendClientHints & AvnOSXThickTitleBar)
+                {
+                    Window.toolbar = [NSToolbar new];
+                    Window.toolbar.showsBaselineSeparator = false;
+                }
+                else
+                {
+                    Window.toolbar = nullptr;
+                }
             }
             else
             {
+                Window.titleVisibility = NSWindowTitleVisible;
                 Window.toolbar = nullptr;
+                [Window setTitlebarAppearsTransparent:false];
+                View.layer.zPosition = 0;
             }
+            
+            [Window setIsExtended:enable];
+            
+            HideOrShowTrafficLights();
+            
+            UpdateStyle();
+            
+            return S_OK;
         }
-        else
-        {
-            Window.titleVisibility = NSWindowTitleVisible;
-            Window.toolbar = nullptr;
-            [Window setTitlebarAppearsTransparent:false];
-            View.layer.zPosition = 0;
-        }
-        
-        [Window setIsExtended:enable];
-        
-        HideOrShowTrafficLights();
-        
-        UpdateStyle();
-        
-        return S_OK;
     }
     
     virtual HRESULT SetExtendClientAreaHints (AvnExtendClientAreaChromeHints hints) override
     {
-        _extendClientHints = hints;
+        START_COM_CALL;
         
-        SetExtendClientArea(_isClientAreaExtended);
+        @autoreleasepool
-        return S_OK;
+        {
+            _extendClientHints = hints;
+            
+            SetExtendClientArea(_isClientAreaExtended);
+            return S_OK;
+        }
     }
     
     virtual HRESULT GetExtendTitleBarHeight (double*ret) override
     {
-        if(ret == nullptr)
+        START_COM_CALL;
+        
+        @autoreleasepool
         {
-            return E_POINTER;
+            if(ret == nullptr)
+            {
+                return E_POINTER;
+            }
+            
+            *ret = [Window getExtendedTitleBarHeight];
+            
+            return S_OK;
         }
-        
-        *ret = [Window getExtendedTitleBarHeight];
-        
-        return S_OK;
     }
     
     virtual HRESULT SetExtendTitleBarHeight (double value) override
     {
-        [StandardContainer SetTitleBarHeightHint:value];
+        START_COM_CALL;
-        return S_OK;
+        
+        @autoreleasepool
+        {
+            [StandardContainer SetTitleBarHeightHint:value];
+            return S_OK;
+        }
     }
     
     void EnterFullScreenMode ()
@@ -978,8 +1083,15 @@ private:
     
     virtual HRESULT SetWindowState (AvnWindowState state) override
     {
+        START_COM_CALL;
+        
         @autoreleasepool
         {
+            if(Window == nullptr)
+            {
+                return  S_OK;
+            }
+            
             if(_actualWindowState == state)
             {
                 return S_OK;
@@ -1926,7 +2038,7 @@ NSArray* AllLoopModes = [NSArray arrayWithObjects: NSDefaultRunLoopMode, NSEvent
     {
         if(![self windowShouldClose:self]) return;
     }
-    
+
     [self close];
 }
 

samples/Sandbox/Program.cs

@@ -4,12 +4,12 @@ namespace Sandbox
 {
     public class Program
     {
-        static void Main(string[] args)
+        static void Main(string[] args) => BuildAvaloniaApp()
-        {
+            .StartWithClassicDesktopLifetime(args);
+
+        public static AppBuilder BuildAvaloniaApp() =>
             AppBuilder.Configure<App>()
                 .UsePlatformDetect()
-                .LogToTrace()
+                .LogToTrace();
-                .StartWithClassicDesktopLifetime(args);
-        }
     }
 }

src/Avalonia.Controls/Shapes/Arc.cs

@@ -0,0 +1,103 @@
+using System;
+using Avalonia.Media;
+
+namespace Avalonia.Controls.Shapes
+{
+    public class Arc : Shape
+    {
+        /// <summary>
+        /// Defines the <see cref="StartAngle"/> property.
+        /// </summary>
+        public static readonly StyledProperty<double> StartAngleProperty =
+            AvaloniaProperty.Register<Arc, double>(nameof(StartAngle), 0.0);
+
+        /// <summary>
+        /// Defines the <see cref="SweepAngle"/> property.
+        /// </summary>
+        public static readonly StyledProperty<double> SweepAngleProperty =
+            AvaloniaProperty.Register<Arc, double>(nameof(SweepAngle), 0.0);
+
+        static Arc()
+        {
+            StrokeThicknessProperty.OverrideDefaultValue<Arc>(1);
+            AffectsGeometry<Arc>(BoundsProperty, StrokeThicknessProperty, StartAngleProperty, SweepAngleProperty);
+        }
+
+        /// <summary>
+        /// Gets or sets the angle at which the arc starts, in degrees.
+        /// </summary>
+        public double StartAngle
+        {
+            get => GetValue(StartAngleProperty);
+            set => SetValue(StartAngleProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets the angle, in degrees, added to the <see cref="StartAngle"/> defining where the arc ends.
+        /// A positive value is clockwise, negative is counter-clockwise.
+        /// </summary>
+        public double SweepAngle
+        {
+            get => GetValue(SweepAngleProperty);
+            set => SetValue(SweepAngleProperty, value);
+        }
+
+        protected override Geometry CreateDefiningGeometry()
+        {
+            var angle1 = DegreesToRad(StartAngle);
+            var angle2 = angle1 + DegreesToRad(SweepAngle);
+
+            var startAngle = Math.Min(angle1, angle2);
+            var sweepAngle = Math.Max(angle1, angle2);
+
+            var normStart = RadToNormRad(startAngle);
+            var normEnd = RadToNormRad(sweepAngle);
+
+            var rect = new Rect(Bounds.Size);
+
+            if ((normStart == normEnd) && (startAngle != sweepAngle)) // Complete ring.
+            {
+                return new EllipseGeometry(rect.Deflate(StrokeThickness / 2));
+            }
+            else if (SweepAngle == 0)
+            {
+                return new StreamGeometry();
+            }
+            else // Partial arc.
+            {
+                var deflatedRect = rect.Deflate(StrokeThickness / 2);
+
+                var centerX = rect.Center.X;
+                var centerY = rect.Center.Y;
+
+                var radiusX = deflatedRect.Width / 2;
+                var radiusY = deflatedRect.Height / 2;
+
+                var angleGap = RadToNormRad(sweepAngle - startAngle);
+
+                var startPoint = GetRingPoint(radiusX, radiusY, centerX, centerY, startAngle);
+                var endPoint = GetRingPoint(radiusX, radiusY, centerX, centerY, sweepAngle);
+
+                var arcGeometry = new StreamGeometry();
+
+                using (var ctx = arcGeometry.Open())
+                {
+                    ctx.BeginFigure(startPoint, false);
+                    ctx.ArcTo(endPoint, new Size(radiusX, radiusY), angleGap, angleGap >= Math.PI,
+                        SweepDirection.Clockwise);
+                    ctx.EndFigure(false);
+                }
+
+                return arcGeometry;
+            }
+        }
+
+        static double DegreesToRad(double inAngle) =>
+            inAngle * Math.PI / 180;
+
+        static double RadToNormRad(double inAngle) => ((inAngle % (Math.PI * 2)) + (Math.PI * 2)) % (Math.PI * 2);
+
+        static Point GetRingPoint(double radiusX, double radiusY, double centerX, double centerY, double angle) =>
+            new Point((radiusX * Math.Cos(angle)) + centerX, (radiusY * Math.Sin(angle)) + centerY);
+    }
+}

src/Avalonia.Controls/Window.cs

@@ -592,6 +592,14 @@ namespace Avalonia.Controls
                     owner.RemoveChild(this);
                 }
 
+                if (_children.Count > 0)
+                {
+                    foreach (var child in _children.ToArray())
+                    {
+                        child.child.Hide();
+                    }
+                }
+
                 Owner = null;
 
                 PlatformImpl?.Hide();
@@ -635,6 +643,22 @@ namespace Avalonia.Controls
                 throw new InvalidOperationException("Cannot re-show a closed window.");
             }
 
+            if (parent != null)
+            {
+                if (parent.PlatformImpl == null)
+                {
+                    throw new InvalidOperationException("Cannot show a window with a closed parent.");
+                }
+                else if (parent == this)
+                {
+                    throw new InvalidOperationException("A Window cannot be its own parent.");
+                }
+                else if (!parent.IsVisible)
+                {
+                    throw new InvalidOperationException("Cannot show window with non-visible parent.");
+                }
+            }
+
             if (IsVisible)
             {
                 return;
@@ -708,11 +732,22 @@ namespace Avalonia.Controls
             {
                 throw new ArgumentNullException(nameof(owner));
             }
-
+            else if (owner.PlatformImpl == null)
-            if (IsVisible)
+            {
+                throw new InvalidOperationException("Cannot show a window with a closed owner.");
+            }
+            else if (owner == this)
+            {
+                throw new InvalidOperationException("A Window cannot be its own owner.");
+            }
+            else if (IsVisible)
             {
                 throw new InvalidOperationException("The window is already being shown.");
             }
+            else if (!owner.IsVisible)
+            {
+                throw new InvalidOperationException("Cannot show window with non-visible parent.");
+            }
 
             RaiseEvent(new RoutedEventArgs(WindowOpenedEvent));
 

tests/Avalonia.Controls.UnitTests/WindowTests.cs

@@ -279,10 +279,11 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var parent = Mock.Of<Window>();
+                var parent = new Window();
                 var renderer = new Mock<IRenderer>();
                 var target = new Window(CreateImpl(renderer));
 
+                parent.Show();
                 target.ShowDialog<object>(parent);
 
                 renderer.Verify(x => x.Start(), Times.Once);
@@ -294,10 +295,11 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var parent = Mock.Of<Window>();
+                var parent = new Window();
                 var target = new Window();
                 var raised = false;
 
+                parent.Show();
                 target.Opened += (s, e) => raised = true;
 
                 target.ShowDialog<object>(parent);
@@ -326,14 +328,15 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var parent = new Mock<Window>();
+                var parent = new Window();
                 var windowImpl = new Mock<IWindowImpl>();
                 windowImpl.SetupProperty(x => x.Closed);
                 windowImpl.Setup(x => x.DesktopScaling).Returns(1);
                 windowImpl.Setup(x => x.RenderScaling).Returns(1);
 
+                parent.Show();
                 var target = new Window(windowImpl.Object);
-                var task = target.ShowDialog<bool>(parent.Object);
+                var task = target.ShowDialog<bool>(parent);
 
                 windowImpl.Object.Closed();
 
@@ -366,14 +369,16 @@ namespace Avalonia.Controls.UnitTests
         {
             using (UnitTestApplication.Start(TestServices.StyledWindow))
             {
-                var parent = new Mock<Window>();
+                var parent = new Window();
                 var windowImpl = new Mock<IWindowImpl>();
                 windowImpl.SetupProperty(x => x.Closed);
                 windowImpl.Setup(x => x.DesktopScaling).Returns(1);
                 windowImpl.Setup(x => x.RenderScaling).Returns(1);
 
+                parent.Show();
+
                 var target = new Window(windowImpl.Object);
-                var task = target.ShowDialog<bool>(parent.Object);
+                var task = target.ShowDialog<bool>(parent);
 
                 windowImpl.Object.Closed();
                 await task;
@@ -381,12 +386,128 @@ namespace Avalonia.Controls.UnitTests
                 var openedRaised = false;
                 target.Opened += (s, e) => openedRaised = true;
 
-                var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => target.ShowDialog<bool>(parent.Object));
+                var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => target.ShowDialog<bool>(parent));
                 Assert.Equal("Cannot re-show a closed window.", ex.Message);
                 Assert.False(openedRaised);
             }
         }
 
+        [Fact]
+        public void Calling_Show_With_Closed_Parent_Window_Should_Throw()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var parent = new Window();
+                var target = new Window();
+
+                parent.Close();
+
+                var ex = Assert.Throws<InvalidOperationException>(() => target.Show(parent));
+                Assert.Equal("Cannot show a window with a closed parent.", ex.Message);
+            }
+        }
+
+        [Fact]
+        public async Task Calling_ShowDialog_With_Closed_Parent_Window_Should_Throw()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var parent = new Window();
+                var target = new Window();
+
+                parent.Close();
+
+                var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => target.ShowDialog(parent));
+                Assert.Equal("Cannot show a window with a closed owner.", ex.Message);
+            }
+        }
+
+        [Fact]
+        public void Calling_Show_With_Invisible_Parent_Window_Should_Throw()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var parent = new Window();
+                var target = new Window();
+
+                var ex = Assert.Throws<InvalidOperationException>(() => target.Show(parent));
+                Assert.Equal("Cannot show window with non-visible parent.", ex.Message);
+            }
+        }
+
+        [Fact]
+        public async Task Calling_ShowDialog_With_Invisible_Parent_Window_Should_Throw()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var parent = new Window();
+                var target = new Window();
+
+                var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => target.ShowDialog(parent));
+                Assert.Equal("Cannot show window with non-visible parent.", ex.Message);
+            }
+        }
+
+        [Fact]
+        public void Calling_Show_With_Self_As_Parent_Window_Should_Throw()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var target = new Window();
+
+                var ex = Assert.Throws<InvalidOperationException>(() => target.Show(target));
+                Assert.Equal("A Window cannot be its own parent.", ex.Message);
+            }
+        }
+
+        [Fact]
+        public async Task Calling_ShowDialog_With_Self_As_Parent_Window_Should_Throw()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var target = new Window();
+
+                var ex = await Assert.ThrowsAsync<InvalidOperationException>(() => target.ShowDialog(target));
+                Assert.Equal("A Window cannot be its own owner.", ex.Message);
+            }
+        }
+
+        [Fact]
+        public void Hiding_Parent_Window_Should_Close_Children()
+        {
+            using (UnitTestApplication.Start(TestServices.MockWindowingPlatform))
+            {
+                var parent = new Window();
+                var child = new Window();
+
+                parent.Show();
+                child.Show(parent);
+
+                parent.Hide();
+
+                Assert.False(parent.IsVisible);
+                Assert.False(child.IsVisible);
+            }
+        }
+
+        [Fact]
+        public void Hiding_Parent_Window_Should_Close_Dialog_Children()
+        {
+            using (UnitTestApplication.Start(TestServices.MockWindowingPlatform))
+            {
+                var parent = new Window();
+                var child = new Window();
+
+                parent.Show();
+                child.ShowDialog(parent);
+
+                parent.Hide();
+
+                Assert.False(parent.IsVisible);
+                Assert.False(child.IsVisible);
+            }
+        }
+
         [Fact]
         public void Window_Should_Be_Centered_When_WindowStartupLocation_Is_CenterScreen()
         {
@@ -686,6 +807,7 @@ namespace Avalonia.Controls.UnitTests
             protected override void Show(Window window)
             {
                 var owner = new Window();
+                owner.Show();
                 window.ShowDialog(owner);
             }
         }