Fix for 2495

MainDemo.Wpf/Pickers.xaml

@@ -50,6 +50,7 @@
                         <DatePicker
                             Width="100"
                             materialDesign:HintAssist.Hint="Pick Date"
+                            materialDesign:TextFieldAssist.HasClearButton="True"
                             Style="{StaticResource MaterialDesignFloatingHintDatePicker}"/>
                     </smtx:XamlDisplay>
 

MaterialDesignThemes.UITests/WPF/ComboBoxes/ComboBoxTests.cs

@@ -54,5 +54,44 @@ public async Task OnFilledComboBoxHelperTextFontSize_ChangesHelperTextFontSize()
             Assert.Equal(20, fontSize);
             recorder.Success();
         }
+
+        [Fact]
+        [Description("Issue 2495")]
+        public async Task OnComboBox_WithClearButton_ClearsSelection()
+        {
+            await using var recorder = new TestRecorder(App);
+
+            var stackPanel = await LoadXaml<StackPanel>($@"
+<StackPanel>
+    <ComboBox materialDesign:HintAssist.Hint=""OS""
+              materialDesign:TextFieldAssist.HasClearButton=""True""
+              SelectedIndex=""1"">
+        <ComboBoxItem Content=""Android"" />
+        <ComboBoxItem Content=""iOS"" />
+        <ComboBoxItem Content=""Linux"" />
+        <ComboBoxItem Content=""Windows"" />
+    </ComboBox>
+</StackPanel>");
+            var comboBox = await stackPanel.GetElement<ComboBox>("/ComboBox");
+            var clearButton = await comboBox.GetElement<Button>("PART_ClearButton");
+
+            int? selectedIndex = await comboBox.GetSelectedIndex();
+            object? text = await comboBox.GetText();
+
+            Assert.True(selectedIndex >= 0);
+            Assert.NotNull(text);
+
+            await clearButton.LeftClick();
+
+            await Wait.For(async () =>
+            {
+                text = await comboBox.GetText();
+                Assert.Null(text);
+                selectedIndex = await comboBox.GetSelectedIndex();
+                Assert.False(selectedIndex >= 0);
+            });
+
+            recorder.Success();
+        }
     }
 }

MaterialDesignThemes.UITests/WPF/DatePickers/DatePickerTests.cs

@@ -1,4 +1,5 @@
-using System.ComponentModel;
+using System;
+using System.ComponentModel;
 using System.Threading.Tasks;
 using System.Windows.Controls;
 using XamlTest;
@@ -19,7 +20,7 @@ public DatePickerTests(ITestOutputHelper output)
         public async Task OnDatePickerHelperTextFontSize_ChangesHelperTextFontSize()
         {
             await using var recorder = new TestRecorder(App);
-
+            
             var stackPanel = await LoadXaml<StackPanel>(@"
 <StackPanel>
     <DatePicker materialDesign:HintAssist.HelperTextFontSize=""20""/>
@@ -33,5 +34,33 @@ public async Task OnDatePickerHelperTextFontSize_ChangesHelperTextFontSize()
             Assert.Equal(20, fontSize);
             recorder.Success();
         }
+
+        [Fact]
+        [Description("Issue 2495")]
+        public async Task OnDatePicker_WithClearButton_ClearsSelectedDate()
+        {
+            await using var recorder = new TestRecorder(App);
+
+            var stackPanel = await LoadXaml<StackPanel>($@"
+<StackPanel>
+    <DatePicker SelectedDate=""{DateTime.Today:d}"" materialDesign:TextFieldAssist.HasClearButton=""True""/>
+</StackPanel>");
+            var datePicker = await stackPanel.GetElement<DatePicker>("/DatePicker");
+            var clearButton = await datePicker.GetElement<Button>("PART_ClearButton");
+
+            DateTime? selectedDate = await datePicker.GetSelectedDate();
+
+            Assert.NotNull(selectedDate);
+
+            await clearButton.LeftClick();
+
+            await Wait.For(async () =>
+            {
+                selectedDate = await datePicker.GetSelectedDate();
+                Assert.Null(selectedDate);
+            });
+
+            recorder.Success();
+        }
     }
 }

MaterialDesignThemes.UITests/WPF/PasswordBoxes/PasswordBoxTests.cs

@@ -4,7 +4,6 @@
 using XamlTest;
 using Xunit;
 using Xunit.Abstractions;
-using Controls = System.Windows.Controls;
 
 namespace MaterialDesignThemes.UITests.WPF.PasswordBoxes
 {
@@ -57,5 +56,35 @@ public async Task OnPasswordBoxHelperTextFontSize_ChangesHelperTextFontSize()
             Assert.Equal(20, fontSize);
             recorder.Success();
         }
+
+        [Fact]
+        [Description("Issue 2495")]
+        public async Task OnPasswordBox_WithClearButton_ClearsPassword()
+        {
+            await using var recorder = new TestRecorder(App);
+
+            var grid = await LoadXaml<Grid>(@"
+<Grid Margin=""30"">
+    <PasswordBox materialDesign:TextFieldAssist.HasClearButton=""True"" />
+</Grid>");
+            var passwordBox = await grid.GetElement<PasswordBox>("/PasswordBox");
+            var clearButton = await passwordBox.GetElement<Button>("PART_ClearButton");
+
+            await passwordBox.SendKeyboardInput($"Test");
+
+            string? password = await passwordBox.GetPassword();
+
+            Assert.NotNull(password);
+
+            await clearButton.LeftClick();
+
+            await Wait.For(async () =>
+            {
+                password = await passwordBox.GetPassword();
+                Assert.Null(password);
+            });
+
+            recorder.Success();
+        }
     }
 }

MaterialDesignThemes.UITests/WPF/TextBoxes/TextBoxTests.cs

@@ -21,7 +21,7 @@ public TextBoxTests(ITestOutputHelper output)
 
         [Fact]
         [Description("Issue 1883")]
-        public async Task OnClearButtonShown_ControlHeighDoesNotChange()
+        public async Task OnClearButtonShown_ControlHeightDoesNotChange()
         {
             await using var recorder = new TestRecorder(App);
 
@@ -56,7 +56,7 @@ public async Task OnClearButtonShown_ControlHeighDoesNotChange()
 
         [Fact]
         [Description("Issue 1883")]
-        public async Task OnClearButtonWithHintShown_ControlHeighDoesNotChange()
+        public async Task OnClearButtonWithHintShown_ControlHeightDoesNotChange()
         {
             await using var recorder = new TestRecorder(App);
 
@@ -125,6 +125,37 @@ public async Task OnTextCleared_MultilineTextBox()
             recorder.Success();
         }
 
+        [Fact]
+        [Description("Issue 2495")]
+        public async Task OnTextBox_WithClearButton_ClearsText()
+        {
+            await using var recorder = new TestRecorder(App);
+
+            var grid = await LoadXaml<Grid>(@"
+<Grid Margin=""30"">
+    <TextBox VerticalAlignment=""Top""
+             Text=""Some Text""
+             materialDesign:TextFieldAssist.HasClearButton=""True"">
+    </TextBox>
+</Grid>");
+            var textBox = await grid.GetElement<TextBox>("/TextBox");
+            var clearButton = await textBox.GetElement<Button>("PART_ClearButton");
+
+            string? text = await textBox.GetText();
+
+            Assert.NotNull(text);
+
+            await clearButton.LeftClick();
+
+            await Wait.For(async () =>
+            {
+                text = await textBox.GetText();
+                Assert.Null(text);
+            });
+
+            recorder.Success();
+        }
+
         [Fact]
         [Description("Issue 2002")]
         public async Task OnTextBoxDisabled_FloatingHintBackgroundIsOpaque()

MaterialDesignThemes.Wpf/Internal/ClearText.cs

@@ -0,0 +1,64 @@
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Controls.Primitives;
+using System.Windows.Input;
+
+namespace MaterialDesignThemes.Wpf.Internal
+{
+    public static class ClearText
+    {
+        public static readonly RoutedCommand ClearCommand = new();
+
+        public static bool GetHandlesClearCommand(DependencyObject obj)
+            => (bool)obj.GetValue(HandlesClearCommandProperty);
+
+        public static void SetHandlesClearCommand(DependencyObject obj, bool value)
+            => obj.SetValue(HandlesClearCommandProperty, value);
+
+        public static readonly DependencyProperty HandlesClearCommandProperty =
+            DependencyProperty.RegisterAttached("HandlesClearCommand", typeof(bool), typeof(ClearText), new PropertyMetadata(false, OnHandlesClearCommandChanged));
+
+        private static void OnHandlesClearCommandChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            if (d is UIElement element)
+            {
+                if ((bool)e.NewValue)
+                {
+                    element.CommandBindings.Add(new CommandBinding(ClearCommand, OnClearCommand));
+                }
+                else
+                {
+                    for (int i = element.CommandBindings.Count - 1; i >= 0; i--)
+                    {
+                        if (element.CommandBindings[i].Command == ClearCommand)
+                        {
+                            element.CommandBindings.RemoveAt(i);
+                        }
+                    }
+                }
+            }
+
+            static void OnClearCommand(object sender, ExecutedRoutedEventArgs e)
+            {
+                switch (e.Source)
+                {
+                    case DatePicker datePicker:
+                        datePicker.SetCurrentValue(DatePicker.SelectedDateProperty, null);
+                        break;
+                    case TextBox textBox:
+                        textBox.SetCurrentValue(TextBox.TextProperty, null);
+                        break;
+                    case ComboBox comboBox:
+                        comboBox.SetCurrentValue(ComboBox.TextProperty, null);
+                        comboBox.SetCurrentValue(Selector.SelectedItemProperty, null);
+                        break;
+                    case PasswordBox passwordBox:
+                        passwordBox.Password = null;
+                        break;
+                }
+                e.Handled = true;
+            }
+        }
+
+    }
+}

MaterialDesignThemes.Wpf/TextFieldAssist.cs

@@ -172,7 +172,7 @@ public static void SetPrefixText(DependencyObject element, string? value)
         /// Controls the visbility of the clear button.
         /// </summary>
         public static readonly DependencyProperty HasClearButtonProperty = DependencyProperty.RegisterAttached(
-            "HasClearButton", typeof(bool), typeof(TextFieldAssist), new PropertyMetadata(false, HasClearButtonChanged));
+            "HasClearButton", typeof(bool), typeof(TextFieldAssist), new PropertyMetadata(false));
 
         public static void SetHasClearButton(DependencyObject element, bool value)
             => element.SetValue(HasClearButtonProperty, value);
@@ -376,51 +376,15 @@ private static void TextBoxOnContextMenuClosing(object sender, ContextMenuEventA
 
         private static void RemoveSpellingSuggestions(ContextMenu menu)
         {
-            foreach (FrameworkElement item in (from item in menu.Items.OfType<FrameworkElement>()
-                where ReferenceEquals(item.Tag, typeof(Spelling))
-                select item).ToList())
+            foreach (FrameworkElement item in
+                (from item in menu.Items.OfType<FrameworkElement>()
+                 where ReferenceEquals(item.Tag, typeof(Spelling))
+                 select item).ToList())
             {
                 menu.Items.Remove(item);
             }
-        }        
-
-        private static void HasClearButtonChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
-        {
-            var box = d as Control; //could be a text box or password box
-            if (box == null)
-            {
-                return;
-            }
-
-            if (box.IsLoaded)
-                SetClearHandler(box);
-            else
-                box.Loaded += (sender, args) =>
-                    SetClearHandler(box);
         }
 
-        private static void SetClearHandler(Control box)
-        {
-            var bValue = GetHasClearButton(box);
-            var clearButton = box.Template.FindName("PART_ClearButton", box) as Button;
-            if (clearButton != null)
-            {
-                RoutedEventHandler handler = (sender, args) =>
-                {
-                    (box as TextBox)?.SetCurrentValue(TextBox.TextProperty, null);
-                    (box as ComboBox)?.SetCurrentValue(ComboBox.TextProperty, null);
-                    if (box is PasswordBox passwordBox)
-                    {
-                        passwordBox.Password = null;
-                    }
-                };
-                if (bValue)
-                    clearButton.Click += handler;
-                else
-                    clearButton.Click -= handler;
-            }
-        }
-
         /// <summary>
         /// Applies the text box view margin.
         /// </summary>

MaterialDesignThemes.Wpf/Themes/MaterialDesignTheme.ComboBox.xaml

@@ -2,7 +2,8 @@
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:converters="clr-namespace:MaterialDesignThemes.Wpf.Converters"
                     xmlns:system="clr-namespace:System;assembly=mscorlib"
-                    xmlns:wpf="clr-namespace:MaterialDesignThemes.Wpf">
+                    xmlns:wpf="clr-namespace:MaterialDesignThemes.Wpf"
+                    xmlns:internal="clr-namespace:MaterialDesignThemes.Wpf.Internal">
 
     <ResourceDictionary.MergedDictionaries>
         <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Shadows.xaml" />
@@ -474,7 +475,8 @@
                     VerticalAlignment="Center"
                     HorizontalAlignment="Right"
                     Padding="0"
-                    Focusable="False">
+                    Focusable="False"
+                    Command="{x:Static internal:ClearText.ClearCommand}">
                     <Button.Margin>
                         <MultiBinding Converter="{StaticResource ComboBoxClearButtonMarginConverter}">
                             <Binding RelativeSource="{RelativeSource TemplatedParent}" Path="Padding" />
@@ -868,6 +870,7 @@
         <Setter Property="wpf:ColorZoneAssist.Mode" Value="Standard" />
         <Setter Property="wpf:HintAssist.Foreground" Value="{DynamicResource PrimaryHueMidBrush}" />
         <Setter Property="Template" Value="{StaticResource MaterialDesignFloatingHintComboBoxTemplate}" />
+        <Setter Property="internal:ClearText.HandlesClearCommand" Value="True" />
         <Style.Triggers>
             <Trigger Property="IsEditable" Value="True">
                 <Setter Property="IsTabStop" Value="False" />

MaterialDesignThemes.Wpf/Themes/MaterialDesignTheme.DatePicker.xaml

@@ -1,6 +1,7 @@
 <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                     xmlns:wpf="clr-namespace:MaterialDesignThemes.Wpf"
+                    xmlns:internal="clr-namespace:MaterialDesignThemes.Wpf.Internal"
                     xmlns:converters="clr-namespace:MaterialDesignThemes.Wpf.Converters">
     <ResourceDictionary.MergedDictionaries>
         <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Calendar.xaml" />
@@ -185,7 +186,8 @@
                                         Height="Auto"
                                         Padding="2 0 0 0"
                                         Focusable="False"
-                                        Style="{DynamicResource MaterialDesignToolButton}">
+                                        Style="{DynamicResource MaterialDesignToolButton}"
+                                        Command="{x:Static internal:ClearText.ClearCommand}">
                                         <Button.Visibility>
                                             <MultiBinding Converter="{StaticResource ClearButtonVisibilityConverter}">
                                                 <Binding RelativeSource="{RelativeSource TemplatedParent}" Path="(wpf:TextFieldAssist.HasClearButton)" />
@@ -439,6 +441,7 @@
         <Setter Property="Validation.ErrorTemplate" Value="{StaticResource MaterialDesignValidationErrorTemplate}" />
         <Setter Property="wpf:TextFieldAssist.UnderlineBrush" Value="{DynamicResource PrimaryHueMidBrush}" />
         <Setter Property="wpf:HintAssist.Foreground" Value="{DynamicResource PrimaryHueMidBrush}" />
+        <Setter Property="internal:ClearText.HandlesClearCommand" Value="True" />
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="{x:Type DatePicker}">
@@ -457,7 +460,7 @@
                             Grid.Column="0"
                             Grid.Row="0"
                             Focusable="{TemplateBinding Focusable}"
-                            Style="{DynamicResource MaterialDesignDatePickerTextBox}"
+                            Style="{StaticResource MaterialDesignDatePickerTextBox}"
                             VerticalContentAlignment="Center"
                             HorizontalAlignment="Stretch"
                             HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"