Enable corner rounding on Windows 11 for dnSpy windows (fixes #325)

dnSpy/dnSpy.Contracts.DnSpy/Controls/Windows11RoundedCorners.cs

@@ -0,0 +1,62 @@
+using System;
+using System.Runtime.InteropServices;
+using System.Windows;
+using System.Windows.Interop;
+
+namespace dnSpy.Contracts.Controls {
+	/// <summary>
+	/// Rounded corner types
+	/// </summary>
+	public enum RoundedCornerType : uint {
+		/// <summary>
+		///	The default behavior. The system determines whether to enable rounded corners
+		/// </summary>
+		Default = 0,
+		/// <summary>
+		/// No rounded corners
+		/// </summary>
+		None = 1,
+		/// <summary>
+		/// Regular rounded corners
+		/// </summary>
+		Regular = 2,
+		/// <summary>
+		/// Small rounded corners
+		/// </summary>
+		Small = 3
+	}
+
+	/// <summary>
+	/// Enabled Windows 11 rounded corners for a <see cref="Window"/> or other supported control
+	/// </summary>
+	public sealed class Windows11RoundedCorners {
+		static readonly bool isWindows11 = Environment.OSVersion.Version is { Major: 10, Build: >= 22000 };
+
+#pragma warning disable CS1591 // Missing XML comment for publicly visible type or member
+		public static readonly DependencyProperty TypeProperty = DependencyProperty.RegisterAttached(
+			"Type", typeof(RoundedCornerType), typeof(Windows11RoundedCorners), new UIPropertyMetadata(RoundedCornerType.Default, TypePropertyChangedCallback));
+
+		public static void SetType(FrameworkElement element, RoundedCornerType value) => element.SetValue(TypeProperty, value);
+		public static RoundedCornerType GetType(FrameworkElement element) => (RoundedCornerType)element.GetValue(TypeProperty);
+#pragma warning restore CS1591 // Missing XML comment for publicly visible type or member
+
+		static void TypePropertyChangedCallback(DependencyObject d, DependencyPropertyChangedEventArgs e) {
+			if (!isWindows11 || d is not IInputElement inputElement)
+				return;
+			PresentationSource.AddSourceChangedHandler(inputElement, (_, args) => {
+				if (args.NewSource is not HwndSource hwndSource)
+					return;
+				IntPtr hwnd = hwndSource.Handle;
+				if (hwnd == IntPtr.Zero)
+					return;
+
+				const uint DWMWA_WINDOW_CORNER_PREFERENCE = 33;
+				var attrValue = (RoundedCornerType)e.NewValue;
+				DwmSetWindowAttribute(hwnd, DWMWA_WINDOW_CORNER_PREFERENCE, ref attrValue, sizeof(uint));
+			});
+		}
+
+		[DllImport("dwmapi", CharSet = CharSet.Unicode, PreserveSig = false)]
+		static extern void DwmSetWindowAttribute(IntPtr hwnd, uint attribute, ref RoundedCornerType pvAttribute, uint cbAttribute);
+	}
+}

dnSpy/dnSpy/Themes/wpf.styles.templates.xaml

@@ -5338,6 +5338,7 @@
         <Setter Property="SnapsToDevicePixels" Value="True"/>
         <Setter Property="Icon" Value="../Images/dnSpy.ico"/>
         <Setter Property="IsDebugging" Value="{DynamicResource IsDebuggingKey}" />
+        <Setter Property="ctrls2:Windows11RoundedCorners.Type" Value="Regular" />
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="{x:Type ctrls2:MetroWindow}">