Fix CheckBox CornerRadius not working

src/MahApps.Metro.Samples/MahApps.Metro.Demo/ExampleViews/ButtonsExample.xaml

@@ -321,7 +321,7 @@
  </StackPanel.Resources>
 
  <Label Content="CheckBox Win10" Style="{DynamicResource DescriptionHeaderStyle}" />
- <CheckBox IsChecked="False" IsEnabled="True" />
+ <CheckBox IsChecked="False" IsEnabled="True" mah:CheckBoxHelper.CheckCornerRadius="2" />
  <CheckBox IsChecked="False" IsEnabled="False" />
  <CheckBox IsChecked="True" IsEnabled="False" />
  <CheckBox IsChecked="True" IsEnabled="True" />

src/MahApps.Metro/Controls/Helper/CheckBoxHelper.cs

@@ -38,6 +38,36 @@ public static void SetCheckSize(DependencyObject obj, double value)
  obj.SetValue(CheckSizeProperty, value);
  }
 
+ public static readonly DependencyProperty CheckCornerRadiusProperty
+ = DependencyProperty.RegisterAttached(
+ "CheckCornerRadius",
+ typeof(CornerRadius),
+ typeof(CheckBoxHelper),
+ new FrameworkPropertyMetadata(
+ new CornerRadius(),
+ FrameworkPropertyMetadataOptions.AffectsMeasure | FrameworkPropertyMetadataOptions.AffectsRender));
+
+ /// <summary>
+ /// Gets the CornerRadius of the CheckBox itself.
+ /// The CheckCornerRadius property allows users to control the roundness of the CheckBox corners independently by setting a radius value for each corner.
+ /// </summary>
+ [Category(AppName.MahApps)]
+ [AttachedPropertyBrowsableForType(typeof(CheckBox))]
+ public static CornerRadius GetCheckCornerRadius(UIElement element)
+ {
+ return (CornerRadius)element.GetValue(CheckCornerRadiusProperty);
+ }
+
+ /// <summary>
+ /// Sets the CornerRadius of the CheckBox itself.
+ /// </summary>
+ [Category(AppName.MahApps)]
+ [AttachedPropertyBrowsableForType(typeof(CheckBox))]
+ public static void SetCheckCornerRadius(UIElement element, CornerRadius value)
+ {
+ element.SetValue(CheckCornerRadiusProperty, value);
+ }
+
  public static readonly DependencyProperty CheckStrokeThicknessProperty
  = DependencyProperty.RegisterAttached(
  "CheckStrokeThickness",

src/MahApps.Metro/Converters/CornerRadiusFilterConverter.cs

@@ -0,0 +1,63 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Globalization;
+using System.Windows;
+using System.Windows.Data;
+
+namespace MahApps.Metro.Converters
+{
+ /// <summary>
+ /// Filters a CornerRadius by the given Filter property. Result can be a new CornerRadius or a value of it's 4 corners.
+ /// </summary>
+ public class CornerRadiusFilterConverter : IValueConverter
+ {
+ public RadiusType Filter { get; set; } = RadiusType.None;
+
+ public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
+ {
+ if (value is CornerRadius cornerRadius)
+ {
+ var filter = this.Filter;
+
+ // yes, we can override it with the parameter value
+ if (parameter is RadiusType radiusType)
+ {
+ filter = radiusType;
+ }
+
+ switch (filter)
+ {
+ default:
+ return cornerRadius;
+ case RadiusType.Left:
+ return new CornerRadius(cornerRadius.TopLeft, 0, 0, cornerRadius.BottomLeft);
+ case RadiusType.Top:
+ return new CornerRadius(cornerRadius.TopLeft, cornerRadius.TopRight, 0, 0);
+ case RadiusType.Right:
+ return new CornerRadius(0, cornerRadius.TopRight, cornerRadius.BottomRight, 0);
+ case RadiusType.Bottom:
+ return new CornerRadius(0, 0, cornerRadius.BottomRight, cornerRadius.BottomLeft);
+ case RadiusType.TopLeft:
+ return cornerRadius.TopLeft;
+ case RadiusType.TopRight:
+ return cornerRadius.TopRight;
+ case RadiusType.BottomRight:
+ return cornerRadius.BottomRight;
+ case RadiusType.BottomLeft:
+ return cornerRadius.BottomLeft;
+ }
+ }
+
+ return Binding.DoNothing;
+ }
+
+ public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
+ {
+ // for now no back converting
+ return DependencyProperty.UnsetValue;
+ }
+ }
+}

src/MahApps.Metro/Styles/Controls.CheckBox.xaml

@@ -1,11 +1,14 @@
 <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:mah="clr-namespace:MahApps.Metro.Controls"
- xmlns:system="clr-namespace:System;assembly=mscorlib">
+ xmlns:system="clr-namespace:System;assembly=mscorlib"
+ xmlns:converters="clr-namespace:MahApps.Metro.Converters">
 
  <!-- ********************************** CheckBoxStyle ********************************** -->
  <system:Double x:Key="CheckBoxBorderThemeThickness">2</system:Double>
  <system:Double x:Key="CheckBoxCheckedStrokeThickness">0</system:Double>
+ <converters:CornerRadiusFilterConverter x:Key="CornerRadiusTopLeftConverter" Filter="TopLeft" />
+ <converters:CornerRadiusFilterConverter x:Key="CornerRadiusBottomRightConverter" Filter="BottomRight" />
 
  <Style x:Key="MahApps.Styles.CheckBox" TargetType="CheckBox">
  <Setter Property="Background" Value="{DynamicResource MahApps.Brushes.CheckBox.BackgroundUnchecked}" />
@@ -42,6 +45,8 @@
  SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}">
  <Rectangle x:Name="NormalRectangle"
  Fill="{TemplateBinding mah:CheckBoxHelper.CheckBackgroundFillUnchecked}"
+ RadiusX="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=(mah:CheckBoxHelper.CheckCornerRadius), Mode=OneWay, Converter={StaticResource CornerRadiusTopLeftConverter}}"
+ RadiusY="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=(mah:CheckBoxHelper.CheckCornerRadius), Mode=OneWay, Converter={StaticResource CornerRadiusBottomRightConverter}}"
  Stroke="{TemplateBinding mah:CheckBoxHelper.CheckBackgroundStrokeUnchecked}"
  StrokeThickness="{TemplateBinding mah:CheckBoxHelper.CheckStrokeThickness}"
  UseLayoutRounding="False" />