Add cs side and interfaces for screens api.

src/Avalonia.Native/AvaloniaNativePlatform.cs

@@ -70,7 +70,6 @@ namespace Avalonia.Native
                 .Bind<IMouseDevice>().ToConstant(MouseDevice)
                 .Bind<IPlatformSettings>().ToConstant(this)
                 .Bind<IWindowingPlatform>().ToConstant(this)
-                .Bind<ISystemDialogImpl>().ToSingleton<SystemDialogImpl>()
                 .Bind<IClipboard>().ToSingleton<ClipboardImpl>()
                 .Bind<IRenderLoop>().ToConstant(new RenderLoop())
                 .Bind<IRenderTimer>().ToConstant(new DefaultRenderTimer(60))

src/Avalonia.Native/Helpers.cs

@@ -19,5 +19,10 @@ namespace Avalonia.Native
         {
             return new Size(size.Width, size.Height);
         }
+
+        public static Rect ToAvaloniaRect (this AvnRect rect)
+        {
+            return new Rect(rect.X, rect.Y, rect.Width, rect.Height);
+        }
     }
 }

src/Avalonia.Native/PopupImpl.cs

@@ -11,7 +11,13 @@ namespace Avalonia.Native
         public PopupImpl(IAvaloniaNativeFactory factory)
         {
             using (var e = new PopupEvents(this))
-                Init(_native = factory.CreatePopup(e));
+                Init(_native = factory.CreatePopup(e), factory.CreateScreens());
+        }
+
+        public override void Dispose()
+        {
+            _native.Dispose();
+            base.Dispose();
         }
 
         class PopupEvents : WindowBaseEvents, IAvnWindowEvents

src/Avalonia.Native/ScreenImpl.cs

@@ -0,0 +1,42 @@
+using System;
+using Avalonia.Native.Interop;
+using Avalonia.Platform;
+
+namespace Avalonia.Native
+{
+    class ScreenImpl : IScreenImpl, IDisposable
+    {
+        private IAvnScreens _native;
+
+        public ScreenImpl(IAvnScreens native)
+        {
+            _native = native;
+        }
+
+        public int ScreenCount => _native.GetScreenCount();
+
+        public Screen[] AllScreens
+        {
+            get
+            {
+                var count = ScreenCount;
+                var result = new Screen[count];
+
+                for(int i = 0; i < count; i++)
+                {
+                    var screen = _native.GetScreen(i);
+
+                    result[i] = new Screen(screen.Bounds.ToAvaloniaRect(), screen.WorkingArea.ToAvaloniaRect(), screen.Primary);
+                }
+
+                return result;
+            }
+        }
+
+        public void Dispose ()
+        {
+            _native.Dispose();
+            _native = null;
+        }
+    }
+}

src/Avalonia.Native/Stubs.cs

@@ -7,20 +7,7 @@ using Avalonia.Input.Platform;
 using Avalonia.Platform;
 
 namespace Avalonia.Native
-{
-    class SystemDialogImpl : ISystemDialogImpl
-    {
-        public Task<string[]> ShowFileDialogAsync(FileDialog dialog, IWindowImpl parent)
-        {
-            return Task.FromResult((string[])null);
-        }
-
-        public Task<string> ShowFolderDialogAsync(OpenFolderDialog dialog, IWindowImpl parent)
-        {
-            return Task.FromResult<string>(null);
-        }
-    }
-
+{ 
     class ClipboardImpl : IClipboard
     {
         public Task ClearAsync()
@@ -38,11 +25,4 @@ namespace Avalonia.Native
             return Task.CompletedTask;
         }
     }
-
-    class ScreenImpl : IScreenImpl
-    {
-        public int ScreenCount => 1;
-
-        public Screen[] AllScreens => new[] { new Screen(new Rect(0, 0, 1600, 900), new Rect(0, 0, 1600, 900), true) };
-    }
 }

src/Avalonia.Native/WindowImpl.cs

@@ -11,7 +11,7 @@ namespace Avalonia.Native
         public WindowImpl(IAvaloniaNativeFactory factory)
         {
             using (var e = new WindowEvents(this))
-                Init(_native = factory.CreateWindow(e));
+                Init(_native = factory.CreateWindow(e), factory.CreateScreens());
         }
 
         class WindowEvents : WindowBaseEvents, IAvnWindowEvents

src/Avalonia.Native/WindowImplBase.cs

@@ -24,9 +24,10 @@ namespace Avalonia.Native
             _mouse = AvaloniaLocator.Current.GetService<IMouseDevice>();
         }
 
-        protected void Init(IAvnWindowBase window)
+        protected void Init(IAvnWindowBase window, IAvnScreens screens)
         {
             _native = window;
+            Screen = new ScreenImpl(screens);
         }
 
         public Size ClientSize 
@@ -144,11 +145,13 @@ namespace Avalonia.Native
             return new ImmediateRenderer(root);
         }
 
-        public void Dispose()
+        public virtual void Dispose()
         {
             _native.Close();
             _native.Dispose();
             _native = null;
+
+            (Screen as ScreenImpl)?.Dispose();
         }
 
 
@@ -217,7 +220,7 @@ namespace Avalonia.Native
         public IPlatformHandle Handle => new PlatformHandle(IntPtr.Zero, "NOT SUPPORTED");
 
 
-        public IScreenImpl Screen => new ScreenImpl();
+        public IScreenImpl Screen { get; private set; }
 
         Action<double> ITopLevelImpl.ScalingChanged { get; set; }
 

src/headers/avalonia-native.h

@@ -9,6 +9,7 @@ struct IAvnMacOptions;
 struct IAvnPlatformThreadingInterface;
 struct IAvnSystemDialogEvents;
 struct IAvnSystemDialogs;
+struct IAvnScreens;
 
 struct AvnSize
 {
@@ -30,6 +31,13 @@ struct AvnPoint
     double X, Y;
 };
 
+struct AvnScreen
+{
+    AvnRect Bounds;
+    AvnRect WorkingArea;
+    bool Primary;
+};
+
 enum AvnRawMouseEventType
 {
     LeaveWindow,
@@ -65,6 +73,7 @@ public:
     virtual HRESULT CreatePopup (IAvnWindowEvents* cb, IAvnPopup** ppv) = 0;
     virtual HRESULT CreatePlatformThreadingInterface(IAvnPlatformThreadingInterface** ppv) = 0;
     virtual HRESULT CreateSystemDialogs (IAvnSystemDialogs** ppv) = 0;
+    virtual HRESULT CreateScreens (IAvnScreens** ppv) = 0;
 };
 
 AVNCOM(IAvnWindowBase, 02) : virtual IUnknown
@@ -179,4 +188,11 @@ AVNCOM(IAvnSystemDialogs, 0d) : virtual IUnknown
                                  const char* filters) = 0;
 };
 
+AVNCOM(IAvnScreens, 0e) : virtual IUnknown
+{
+    virtual HRESULT GetScreenCount (int* ret) = 0;
+    virtual HRESULT GetScreen (int index, AvnScreen** ret) = 0;
+    
+};
+
 extern "C" IAvaloniaNativeFactory* CreateAvaloniaNative();