feat: implement closing related features.

demo/Ursa.Demo/ViewModels/DialogDemoViewModel.cs

@@ -1,8 +1,6 @@
 using System;
 using System.Threading.Tasks;
 using System.Windows.Input;
-using Avalonia.Controls;
-using Avalonia.Controls.Shapes;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using Ursa.Controls;
@@ -30,11 +28,11 @@ public class DialogDemoViewModel: ObservableObject
 
     private async Task ShowGlobalOverlayDialog()
     {
-        await DialogBox.ShowOverlayAsync<Banner, DateTime>(DateTime.Now, "GlobalHost");
+        await DialogBox.ShowOverlayAsync<ButtonGroupDemo, ButtonGroupDemoViewModel>(new ButtonGroupDemoViewModel(), "GlobalHost");
     }
 
     private async Task ShowLocalOverlayDialog()
     {
-        await DialogBox.ShowOverlayAsync<Banner, DateTime>(DateTime.Now, "LocalHost");
+        await DialogBox.ShowOverlayAsync<ButtonGroupDemo, ButtonGroupDemoViewModel>(new ButtonGroupDemoViewModel(), "LocalHost");
     }
 }

src/Ursa.Themes.Semi/Controls/Dialog.axaml

@@ -1,13 +1,29 @@
-<ResourceDictionary xmlns="https://github.com/avaloniaui"
+<ResourceDictionary
+    xmlns="https://github.com/avaloniaui"
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
     xmlns:u="https://irihi.tech/ursa">
     <!--  Add Resources Here  -->
     <ControlTheme x:Key="{x:Type u:DialogControl}" TargetType="u:DialogControl">
         <Setter Property="Template">
             <ControlTemplate TargetType="u:DialogControl">
-                <Border HorizontalAlignment="Center" VerticalAlignment="Center" Theme="{DynamicResource CardBorder}" Width="100" Height="100" IsHitTestVisible="True">
+                <Border
+                    Classes="Shadow"
+                    HorizontalAlignment="Center"
+                    VerticalAlignment="Center"
+                    IsHitTestVisible="True"
+                    Theme="{DynamicResource CardBorder}">
                     <Grid RowDefinitions="Auto, *, Auto">
-                        <ContentPresenter Content="{TemplateBinding Content}"></ContentPresenter>
+                        <StackPanel Grid.Row="0" HorizontalAlignment="Right">
+                            <Button Name="{x:Static u:DialogControl.PART_CloseButton}">Close</Button>
+                        </StackPanel>
+                        <ContentPresenter
+                            Grid.Row="0"
+                            Grid.RowSpan="2"
+                            Content="{TemplateBinding Content}" />
+                        <StackPanel Grid.Row="2">
+                            <Button>OK</Button>
+                            <Button>Cancel</Button>
+                        </StackPanel>
                     </Grid>
                 </Border>
             </ControlTemplate>
@@ -26,11 +42,15 @@
         <Setter Property="WindowStartupLocation" Value="CenterOwner" />
         <Setter Property="ExtendClientAreaTitleBarHeightHint" Value="1" />
         <Setter Property="ExtendClientAreaToDecorationsHint" Value="True" />
-        <Setter Property="ExtendClientAreaChromeHints" Value="SystemChrome"/>
+        <Setter Property="ExtendClientAreaChromeHints" Value="SystemChrome" />
         <Setter Property="SystemDecorations">
-            <OnPlatform >
+            <OnPlatform>
-                <OnPlatform.Windows><SystemDecorations>Full</SystemDecorations></OnPlatform.Windows>
+                <OnPlatform.Windows>
-                <OnPlatform.Default><SystemDecorations>BorderOnly</SystemDecorations></OnPlatform.Default>
+                    <SystemDecorations>Full</SystemDecorations>
+                </OnPlatform.Windows>
+                <OnPlatform.Default>
+                    <SystemDecorations>BorderOnly</SystemDecorations>
+                </OnPlatform.Default>
             </OnPlatform>
         </Setter>
         <Setter Property="CanResize" Value="False" />
@@ -40,10 +60,10 @@
                     <Border Name="PART_TransparencyFallback" IsHitTestVisible="False" />
                     <Border Background="{TemplateBinding Background}" IsHitTestVisible="False" />
                     <Panel Margin="{TemplateBinding WindowDecorationMargin}" Background="Transparent" />
-                    <ChromeOverlayLayer></ChromeOverlayLayer>
+                    <ChromeOverlayLayer />
                     <Grid RowDefinitions="Auto, *, Auto">
                         <Button Name="{x:Static u:DialogWindow.PART_CloseButton}" VerticalAlignment="Top">Close</Button>
-                        <ContentPresenter Content="{TemplateBinding Content}"></ContentPresenter>
+                        <ContentPresenter Content="{TemplateBinding Content}" />
                     </Grid>
                 </Panel>
             </ControlTemplate>

src/Ursa/Controls/Dialog/DialogBox.cs

@@ -58,7 +58,7 @@ public static class DialogBox
         };
         t.DataContext = vm;
         var host = OverlayDialogManager.GetOverlayDialogHost(hostId);
-        host?.Children.Add(t);
+        host?.AddDialog(t);
         return null;
     }
 }

src/Ursa/Controls/Dialog/DialogControl.cs

@@ -13,15 +13,36 @@ public class DialogControl: ContentControl
     
     
     private Button? _closeButton;
-    public event EventHandler OnClose;
+    public event EventHandler<object?> OnClose;
 
     protected override void OnApplyTemplate(TemplateAppliedEventArgs e)
     {
         base.OnApplyTemplate(e);
+        if (_closeButton != null)
+        {
+            _closeButton.Click -= Close;
+        }
+        _closeButton = e.NameScope.Find<Button>(PART_CloseButton);
+        if (_closeButton is not null)
+        {
+            _closeButton.Click += Close;
+        }
     }
 
     public void Show()
     {
         
     }
+
+    private void Close(object sender, object args)
+    {
+        if (this.DataContext is IDialogContext context)
+        {
+            OnClose?.Invoke(this, context.DefaultCloseResult);
+        }
+        else
+        {
+            OnClose?.Invoke(this, null);
+        }
+    }
 }

src/Ursa/Controls/Dialog/DialogOptions.cs

@@ -1,6 +1,6 @@
 namespace Ursa.Controls;
 
-public record OverlayDialogOptions
+public record DialogOptions
 {
     public bool ShowCloseButton { get; set; } = true;
 }

src/Ursa/Controls/Dialog/OverlayDialogHost.cs

@@ -84,6 +84,17 @@ public class OverlayDialogHost: Canvas
     public void AddDialog(DialogControl control)
     {
         this.Children.Add(control);
+        control.OnClose += OnDialogClose;
+    }
+
+    private void OnDialogClose(object sender, object? e)
+    {
+        if (sender is DialogControl control)
+        {
+            this.Children.Remove(control);
+            control.OnClose -= OnDialogClose;
+        }
+        
     }
 
     public void AddModalDialog(DialogControl control)