feat: WIP dialog window.

src/Ursa/Controls/Dialog/DialogBox.cs

@@ -1,5 +1,6 @@
 using Avalonia;
 using Avalonia.Controls;
+using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Controls.Shapes;
 using Avalonia.Media;
 
@@ -7,18 +8,46 @@ namespace Ursa.Controls;
 
 public static class DialogBox
 {
-    public static async Task ShowAsync()
+    public static async Task<TResult?> ShowAsync<TView, TViewModel, TResult>(TViewModel vm) where TView : Control, new()
     {
-        return;
+        var window = new DialogWindow()
+        {
+            Content = new TView()
+            {
+                DataContext = vm,
+            },
+            DataContext = vm,
+        };
+        var lifetime = Application.Current?.ApplicationLifetime;
+        if (lifetime is IClassicDesktopStyleApplicationLifetime classLifetime)
+        {
+            var main = classLifetime.MainWindow;
+            if (main is null)
+            {
+                window.Show();
+                return default(TResult);
+            }
+            else
+            {
+                var result = await window.ShowDialog<TResult>(main);
+                return result;
+            }
+        }
+        else
+        {
+            return default(TResult);
+        }
     }
-
-    public static async Task ShowAsync<TView, TViewModel>(TViewModel vm) 
-        where TView: Control, new()
-        where TViewModel: new()
+    
+    public static async Task<TResult> ShowAsync<TView, TViewModel, TResult>(Window owner, TViewModel vm) where 
+        TView: Control, new()
     {
-        TView t = new TView();
-        t.DataContext = vm;
+        var window = new DialogWindow();
+        window.Content = new TView();
+        window.DataContext = vm;
+        return await window.ShowDialog<TResult>(owner);
     }
+    
 
     public static async Task<object?> ShowOverlayAsync<TView, TViewModel>(TViewModel vm, string hostId)
         where TView : Control, new()

src/Ursa/Controls/Dialog/DialogControl.cs

@@ -1,8 +1,27 @@
 using Avalonia.Controls;
+using Avalonia.Controls.Metadata;
+using Avalonia.Controls.Primitives;
+using Avalonia.Interactivity;
 
 namespace Ursa.Controls;
 
+[TemplatePart(PART_CloseButton, typeof(Button))]
 public class DialogControl: ContentControl
 {
+    public const string PART_CloseButton = "PART_CloseButton";
     
+    
+    
+    private Button? _closeButton;
+    public event EventHandler OnClose;
+
+    protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
+    {
+        base.OnApplyTemplate(e);
+    }
+
+    public void Show()
+    {
+        
+    }
 }

src/Ursa/Controls/Dialog/DialogWindow.cs

@@ -0,0 +1,30 @@
+using Avalonia.Controls;
+using Avalonia.Controls.Metadata;
+using Avalonia.Controls.Primitives;
+
+namespace Ursa.Controls;
+
+[TemplatePart(PART_CloseButton, typeof(Button))]
+public class DialogWindow: Window
+{
+    public const string PART_CloseButton = "PART_CloseButton";
+    
+    protected override Type StyleKeyOverride { get; } = typeof(DialogWindow);
+
+    private Button? _closeButton;
+
+    protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
+    {
+        base.OnApplyTemplate(e);
+        _closeButton = e.NameScope.Find<Button>(PART_CloseButton);
+        
+        if (_closeButton != null)
+        {
+            _closeButton.Click += (sender, args) =>
+            {
+                Close();
+            };
+        }
+        
+    }
+}

src/Ursa/Controls/Dialog/IDialogContext.cs

@@ -2,5 +2,6 @@ namespace Ursa.Controls;
 
 public interface IDialogContext
 {
-    
+    object Close();
+    T? Close<T>();
 }

src/Ursa/Controls/Dialog/OverlayDialogHost.cs

@@ -1,14 +1,26 @@
+using System.Collections.Specialized;
 using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Controls.Primitives;
+using Avalonia.Controls.Shapes;
 using Avalonia.Input;
 using Avalonia.Media;
 using Avalonia.Utilities;
+using Avalonia.VisualTree;
 
-namespace Ursa.Controls;
+namespace Ursa.Controls; 
 
 public class OverlayDialogHost: Canvas
 {
+    private readonly List<DialogControl> _dialogs = new();
+    private readonly List<DialogControl> _modalDialogs = new();
+
+    private Rectangle _overlayMask = new()
+    {
+        Fill = new SolidColorBrush(new Color(1, 0, 0, 0)),
+        [Rectangle.ZIndexProperty] = 0,
+    };
+    
     public static readonly StyledProperty<string> HostIdProperty = AvaloniaProperty.Register<OverlayDialogHost, string>(
         nameof(HostId));
 
@@ -39,13 +51,18 @@ public class OverlayDialogHost: Canvas
         {
             if (e.GetCurrentPoint(this).Properties.IsLeftButtonPressed)
             {
+                var parent  = item.FindAncestorOfType<DialogControl>();
+                if (parent is null)
+                {
+                    return;
+                }
                 var p = e.GetPosition(this);
                 var left=  p.X - _lastPoint.X;
                 var top = p.Y - _lastPoint.Y;
-                left = MathUtilities.Clamp(left, 0, Bounds.Width - item.Bounds.Width);
-                top = MathUtilities.Clamp(top, 0, Bounds.Height - item.Bounds.Height);
-                Canvas.SetLeft(item, left);
-                Canvas.SetTop(item, top);
+                left = MathUtilities.Clamp(left, 0, Bounds.Width - parent.Bounds.Width);
+                top = MathUtilities.Clamp(top, 0, Bounds.Height - parent.Bounds.Height);
+                Canvas.SetLeft(parent, left);
+                Canvas.SetTop(parent, top);
             }
         }
     }
@@ -55,7 +72,22 @@ public class OverlayDialogHost: Canvas
         base.OnPointerPressed(e);
         if (e.Source is Control item)
         {
-            _lastPoint = e.GetPosition(item);
+            var parent  = item.FindAncestorOfType<DialogControl>();
+            if (parent is null)
+            {
+                return;
+            }
+            _lastPoint = e.GetPosition(parent);
         }
     }
+
+    public void AddDialog(DialogControl control)
+    {
+        this.Children.Add(control);
+    }
+
+    public void AddModalDialog(DialogControl control)
+    {
+        this.Children.Add(control);
+    }
 }