fixed a binding error of CheckComboBox

src/Net_40/HandyControl_Net_40/Themes/Styles/Base/CheckComboBoxBaseStyle.xaml

@@ -40,6 +40,39 @@
         </Setter>
     </Style>
 
+    <Style x:Key="CheckComboBoxWatermarkToggleButton" TargetType="ToggleButton">
+        <Setter Property="OverridesDefaultStyle" Value="true"/>
+        <Setter Property="Foreground" Value="{DynamicResource ThirdlyTextBrush}"/>
+        <Setter Property="IsTabStop" Value="false"/>
+        <Setter Property="Focusable" Value="false"/>
+        <Setter Property="ClickMode" Value="Press"/>
+        <Setter Property="Template">
+            <Setter.Value>
+                <ControlTemplate TargetType="ToggleButton">
+                    <Grid>
+                        <Grid.ColumnDefinitions>
+                            <ColumnDefinition/>
+                            <ColumnDefinition Width="30"/>
+                        </Grid.ColumnDefinitions>
+                        <Border Grid.ColumnSpan="2" CornerRadius="{Binding Path=(hc:BorderElement.CornerRadius),RelativeSource={RelativeSource TemplatedParent}}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" SnapsToDevicePixels="true"/>
+                        <Path Grid.Column="1" x:Name="arrow" Data="{StaticResource DownGeometry}" Stretch="Uniform" Fill="{TemplateBinding BorderBrush}" HorizontalAlignment="Center" Margin="7" VerticalAlignment="Center"/>
+                        <Border Margin="1" Grid.Column="0" Visibility="{Binding SelectedItem,RelativeSource={RelativeSource AncestorType=hc:CheckComboBox},Converter={StaticResource Object2VisibilityReConverter}}">
+                            <ContentPresenter Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
+                        </Border>
+                    </Grid>
+                    <ControlTemplate.Triggers>
+                        <Trigger Property="IsChecked" Value="True">
+                            <Setter Property="Data" TargetName="arrow" Value="{StaticResource UpGeometry}"/>
+                        </Trigger>
+                        <Trigger Property="IsEnabled" Value="False">
+                            <Setter Property="Opacity" Value=".4"/>
+                        </Trigger>
+                    </ControlTemplate.Triggers>
+                </ControlTemplate>
+            </Setter.Value>
+        </Setter>
+    </Style>
+
     <Style x:Key="CheckComboBoxItemBaseStyle" TargetType="hc:CheckComboBoxItem">
         <Setter Property="SnapsToDevicePixels" Value="True"/>
         <Setter Property="Padding" Value="{StaticResource DefaultControlPadding}"/>
@@ -182,7 +215,7 @@
                     </hc:ToggleBlock>
                 </Border>
             </Popup>
-            <ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}"/>
+            <ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}"/>
             <Border Grid.Row="1" Grid.Column="0" Margin="1,0">
                 <WrapPanel Name="PART_Panel" Margin="3,1,3,4"/>
             </Border>
@@ -247,7 +280,7 @@
                     </hc:ToggleBlock>
                 </Border>
             </Popup>
-            <ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}"/>
+            <ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}"/>
             <Border Grid.Column="1" Margin="1,0">
                 <WrapPanel Name="PART_Panel" Margin="3,1,3,4"/>
             </Border>
@@ -337,7 +370,7 @@
                 </Border>
             </Popup>
             <TextBlock Grid.Column="0" Grid.ColumnSpan="2" FontSize="12" Text="{TemplateBinding ErrorStr}" Name="TextBlockError" VerticalAlignment="Bottom" Margin="9,0,0,4" Foreground="{DynamicResource DangerBrush}" Grid.Row="1"/>
-            <ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}"/>
+            <ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}"/>
             <Border Grid.Row="1" Grid.Column="0" Margin="1,0">
                 <WrapPanel Name="PART_Panel" Margin="3,1,3,4"/>
             </Border>
@@ -442,7 +475,7 @@
                 </Border>
             </Popup>
             <TextBlock Grid.Column="1" Grid.ColumnSpan="2" FontSize="12" Text="{TemplateBinding ErrorStr}" Name="TextBlockError" VerticalAlignment="Bottom" Margin="9,0,0,4" Foreground="{DynamicResource DangerBrush}"/>
-            <ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}"/>
+            <ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}"/>
             <Border Grid.Column="1" Margin="1,0">
                 <WrapPanel Name="PART_Panel" Margin="3,1,3,4"/>
             </Border>

src/Net_40/HandyControl_Net_40/Themes/Theme.xaml

@@ -6734,6 +6734,38 @@
 			</Setter.Value>
 		</Setter>
 	</Style>
+	<Style x:Key="CheckComboBoxWatermarkToggleButton" TargetType="ToggleButton">
+		<Setter Property="OverridesDefaultStyle" Value="true" />
+		<Setter Property="Foreground" Value="{DynamicResource ThirdlyTextBrush}" />
+		<Setter Property="IsTabStop" Value="false" />
+		<Setter Property="Focusable" Value="false" />
+		<Setter Property="ClickMode" Value="Press" />
+		<Setter Property="Template">
+			<Setter.Value>
+				<ControlTemplate TargetType="ToggleButton">
+					<Grid>
+						<Grid.ColumnDefinitions>
+							<ColumnDefinition />
+							<ColumnDefinition Width="30" />
+						</Grid.ColumnDefinitions>
+						<Border Grid.ColumnSpan="2" CornerRadius="{Binding Path=(hc:BorderElement.CornerRadius),RelativeSource={RelativeSource TemplatedParent}}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" SnapsToDevicePixels="true" />
+						<Path Grid.Column="1" x:Name="arrow" Data="{StaticResource DownGeometry}" Stretch="Uniform" Fill="{TemplateBinding BorderBrush}" HorizontalAlignment="Center" Margin="7" VerticalAlignment="Center" />
+						<Border Margin="1" Grid.Column="0" Visibility="{Binding SelectedItem,RelativeSource={RelativeSource AncestorType=hc:CheckComboBox},Converter={StaticResource Object2VisibilityReConverter}}">
+							<ContentPresenter Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}" />
+						</Border>
+					</Grid>
+					<ControlTemplate.Triggers>
+						<Trigger Property="IsChecked" Value="True">
+							<Setter Property="Data" TargetName="arrow" Value="{StaticResource UpGeometry}" />
+						</Trigger>
+						<Trigger Property="IsEnabled" Value="False">
+							<Setter Property="Opacity" Value=".4" />
+						</Trigger>
+					</ControlTemplate.Triggers>
+				</ControlTemplate>
+			</Setter.Value>
+		</Setter>
+	</Style>
 	<Style x:Key="CheckComboBoxItemBaseStyle" TargetType="hc:CheckComboBoxItem">
 		<Setter Property="SnapsToDevicePixels" Value="True" />
 		<Setter Property="Padding" Value="{StaticResource DefaultControlPadding}" />
@@ -6873,7 +6905,7 @@
 					</hc:ToggleBlock>
 				</Border>
 			</Popup>
-			<ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}" />
+			<ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}" />
 			<Border Grid.Row="1" Grid.Column="0" Margin="1,0">
 				<WrapPanel Name="PART_Panel" Margin="3,1,3,4" />
 			</Border>
@@ -6937,7 +6969,7 @@
 					</hc:ToggleBlock>
 				</Border>
 			</Popup>
-			<ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}" />
+			<ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}" />
 			<Border Grid.Column="1" Margin="1,0">
 				<WrapPanel Name="PART_Panel" Margin="3,1,3,4" />
 			</Border>
@@ -7025,7 +7057,7 @@
 				</Border>
 			</Popup>
 			<TextBlock Grid.Column="0" Grid.ColumnSpan="2" FontSize="12" Text="{TemplateBinding ErrorStr}" Name="TextBlockError" VerticalAlignment="Bottom" Margin="9,0,0,4" Foreground="{DynamicResource DangerBrush}" Grid.Row="1" />
-			<ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}" />
+			<ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}" />
 			<Border Grid.Row="1" Grid.Column="0" Margin="1,0">
 				<WrapPanel Name="PART_Panel" Margin="3,1,3,4" />
 			</Border>
@@ -7129,7 +7161,7 @@
 				</Border>
 			</Popup>
 			<TextBlock Grid.Column="1" Grid.ColumnSpan="2" FontSize="12" Text="{TemplateBinding ErrorStr}" Name="TextBlockError" VerticalAlignment="Bottom" Margin="9,0,0,4" Foreground="{DynamicResource DangerBrush}" />
-			<ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}" />
+			<ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}" />
 			<Border Grid.Column="1" Margin="1,0">
 				<WrapPanel Name="PART_Panel" Margin="3,1,3,4" />
 			</Border>

src/Shared/HandyControlDemo_Shared/UserControl/Controls/CheckComboBoxDemoCtl.xaml

@@ -26,7 +26,7 @@
                 <hc:CheckComboBox MaxWidth="380" ItemsSource="{Binding DataList}" hc:InfoElement.Placeholder="{ex:Lang Key={x:Static langs:LangKeys.PlsEnterContent}}" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr2}}" Style="{StaticResource CheckComboBoxPlus}" hc:InfoElement.Necessary="True" Margin="0,16,0,0"/>
 
                 <hc:CheckComboBox MaxWidth="380" ItemsSource="{Binding DataList}" ShowClearButton="True" Width="380" hc:InfoElement.TitleWidth="140" hc:InfoElement.TitlePlacement="Left" Style="{StaticResource CheckComboBoxPlus}" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr3}}" Margin="0,32,0,0" ShowSelectAllButton="True"/>
-                <hc:CheckComboBox MaxWidth="380" ItemsSource="{Binding DataList}" Width="380" hc:InfoElement.TitleWidth="140" hc:InfoElement.TitlePlacement="Left" hc:InfoElement.Placeholder="{ex:Lang Key={x:Static langs:LangKeys.PlsEnterContent}}" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr3}}" Style="{StaticResource CheckComboBoxPlus}" hc:InfoElement.Necessary="True" Margin="0,16,0,0"/>
+                <hc:CheckComboBox MaxWidth="380" ItemsSource="{Binding DataList}" ShowClearButton="True" Width="380" hc:InfoElement.TitleWidth="140" hc:InfoElement.TitlePlacement="Left" hc:InfoElement.Placeholder="{ex:Lang Key={x:Static langs:LangKeys.PlsEnterContent}}" hc:InfoElement.Title="{ex:Lang Key={x:Static langs:LangKeys.TitleDemoStr3}}" Style="{StaticResource CheckComboBoxPlus}" hc:InfoElement.Necessary="True" Margin="0,16,0,0"/>
             </StackPanel>
         </StackPanel>
     </hc:TransitioningContentControl>

src/Shared/HandyControl_Shared/Themes/Styles/Base/CheckComboBoxBaseStyle.xaml

@@ -40,6 +40,39 @@
         </Setter>
     </Style>
 
+    <Style x:Key="CheckComboBoxWatermarkToggleButton" TargetType="ToggleButton">
+        <Setter Property="OverridesDefaultStyle" Value="true"/>
+        <Setter Property="Foreground" Value="{DynamicResource ThirdlyTextBrush}"/>
+        <Setter Property="IsTabStop" Value="false"/>
+        <Setter Property="Focusable" Value="false"/>
+        <Setter Property="ClickMode" Value="Press"/>
+        <Setter Property="Template">
+            <Setter.Value>
+                <ControlTemplate TargetType="ToggleButton">
+                    <Grid>
+                        <Grid.ColumnDefinitions>
+                            <ColumnDefinition/>
+                            <ColumnDefinition Width="30"/>
+                        </Grid.ColumnDefinitions>
+                        <Border Grid.ColumnSpan="2" CornerRadius="{Binding Path=(hc:BorderElement.CornerRadius),RelativeSource={RelativeSource TemplatedParent}}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" SnapsToDevicePixels="true"/>
+                        <Path Grid.Column="1" x:Name="arrow" Data="{StaticResource DownGeometry}" Stretch="Uniform" Fill="{TemplateBinding BorderBrush}" HorizontalAlignment="Center" Margin="7" VerticalAlignment="Center"/>
+                        <Border Margin="1" Grid.Column="0" Visibility="{Binding SelectedItem,RelativeSource={RelativeSource AncestorType=hc:CheckComboBox},Converter={StaticResource Object2VisibilityReConverter}}">
+                            <ContentPresenter Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
+                        </Border>
+                    </Grid>
+                    <ControlTemplate.Triggers>
+                        <Trigger Property="IsChecked" Value="True">
+                            <Setter Property="Data" TargetName="arrow" Value="{StaticResource UpGeometry}"/>
+                        </Trigger>
+                        <Trigger Property="IsEnabled" Value="False">
+                            <Setter Property="Opacity" Value=".4"/>
+                        </Trigger>
+                    </ControlTemplate.Triggers>
+                </ControlTemplate>
+            </Setter.Value>
+        </Setter>
+    </Style>
+
     <Style x:Key="CheckComboBoxItemBaseStyle" TargetType="hc:CheckComboBoxItem">
         <Setter Property="SnapsToDevicePixels" Value="True"/>
         <Setter Property="Padding" Value="{StaticResource DefaultControlPadding}"/>
@@ -189,7 +222,7 @@
                     </hc:ToggleBlock>
                 </Border>
             </Popup>
-            <ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}"/>
+            <ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}"/>
             <Border Grid.Row="1" Grid.Column="0" Margin="1,0">
                 <WrapPanel Name="PART_Panel" Margin="3,1,3,4"/>
             </Border>
@@ -261,7 +294,7 @@
                     </hc:ToggleBlock>
                 </Border>
             </Popup>
-            <ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}"/>
+            <ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}"/>
             <Border Grid.Column="1" Margin="1,0">
                 <WrapPanel Name="PART_Panel" Margin="3,1,3,4"/>
             </Border>
@@ -358,7 +391,7 @@
                 </Border>
             </Popup>
             <TextBlock Grid.Column="0" Grid.ColumnSpan="2" FontSize="12" Text="{TemplateBinding ErrorStr}" Name="TextBlockError" VerticalAlignment="Bottom" Margin="9,0,0,4" Foreground="{DynamicResource DangerBrush}" Grid.Row="1"/>
-            <ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}"/>
+            <ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}"/>
             <Border Grid.Row="1" Grid.Column="0" Margin="1,0">
                 <WrapPanel Name="PART_Panel" Margin="3,1,3,4"/>
             </Border>
@@ -470,7 +503,7 @@
                 </Border>
             </Popup>
             <TextBlock Grid.Column="1" Grid.ColumnSpan="2" FontSize="12" Text="{TemplateBinding ErrorStr}" Name="TextBlockError" VerticalAlignment="Bottom" Margin="9,0,0,4" Foreground="{DynamicResource DangerBrush}"/>
-            <ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}"/>
+            <ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}"/>
             <Border Grid.Column="1" Margin="1,0">
                 <WrapPanel Name="PART_Panel" Margin="3,1,3,4"/>
             </Border>

src/Shared/HandyControl_Shared/Themes/Theme.xaml

@@ -6817,6 +6817,38 @@
 			</Setter.Value>
 		</Setter>
 	</Style>
+	<Style x:Key="CheckComboBoxWatermarkToggleButton" TargetType="ToggleButton">
+		<Setter Property="OverridesDefaultStyle" Value="true" />
+		<Setter Property="Foreground" Value="{DynamicResource ThirdlyTextBrush}" />
+		<Setter Property="IsTabStop" Value="false" />
+		<Setter Property="Focusable" Value="false" />
+		<Setter Property="ClickMode" Value="Press" />
+		<Setter Property="Template">
+			<Setter.Value>
+				<ControlTemplate TargetType="ToggleButton">
+					<Grid>
+						<Grid.ColumnDefinitions>
+							<ColumnDefinition />
+							<ColumnDefinition Width="30" />
+						</Grid.ColumnDefinitions>
+						<Border Grid.ColumnSpan="2" CornerRadius="{Binding Path=(hc:BorderElement.CornerRadius),RelativeSource={RelativeSource TemplatedParent}}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" SnapsToDevicePixels="true" />
+						<Path Grid.Column="1" x:Name="arrow" Data="{StaticResource DownGeometry}" Stretch="Uniform" Fill="{TemplateBinding BorderBrush}" HorizontalAlignment="Center" Margin="7" VerticalAlignment="Center" />
+						<Border Margin="1" Grid.Column="0" Visibility="{Binding SelectedItem,RelativeSource={RelativeSource AncestorType=hc:CheckComboBox},Converter={StaticResource Object2VisibilityReConverter}}">
+							<ContentPresenter Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}" />
+						</Border>
+					</Grid>
+					<ControlTemplate.Triggers>
+						<Trigger Property="IsChecked" Value="True">
+							<Setter Property="Data" TargetName="arrow" Value="{StaticResource UpGeometry}" />
+						</Trigger>
+						<Trigger Property="IsEnabled" Value="False">
+							<Setter Property="Opacity" Value=".4" />
+						</Trigger>
+					</ControlTemplate.Triggers>
+				</ControlTemplate>
+			</Setter.Value>
+		</Setter>
+	</Style>
 	<Style x:Key="CheckComboBoxItemBaseStyle" TargetType="hc:CheckComboBoxItem">
 		<Setter Property="SnapsToDevicePixels" Value="True" />
 		<Setter Property="Padding" Value="{StaticResource DefaultControlPadding}" />
@@ -6963,7 +6995,7 @@
 					</hc:ToggleBlock>
 				</Border>
 			</Popup>
-			<ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}" />
+			<ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}" />
 			<Border Grid.Row="1" Grid.Column="0" Margin="1,0">
 				<WrapPanel Name="PART_Panel" Margin="3,1,3,4" />
 			</Border>
@@ -7034,7 +7066,7 @@
 					</hc:ToggleBlock>
 				</Border>
 			</Popup>
-			<ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}" />
+			<ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}" />
 			<Border Grid.Column="1" Margin="1,0">
 				<WrapPanel Name="PART_Panel" Margin="3,1,3,4" />
 			</Border>
@@ -7129,7 +7161,7 @@
 				</Border>
 			</Popup>
 			<TextBlock Grid.Column="0" Grid.ColumnSpan="2" FontSize="12" Text="{TemplateBinding ErrorStr}" Name="TextBlockError" VerticalAlignment="Bottom" Margin="9,0,0,4" Foreground="{DynamicResource DangerBrush}" Grid.Row="1" />
-			<ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}" />
+			<ToggleButton Grid.Row="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" Grid.Column="0" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}" />
 			<Border Grid.Row="1" Grid.Column="0" Margin="1,0">
 				<WrapPanel Name="PART_Panel" Margin="3,1,3,4" />
 			</Border>
@@ -7240,7 +7272,7 @@
 				</Border>
 			</Popup>
 			<TextBlock Grid.Column="1" Grid.ColumnSpan="2" FontSize="12" Text="{TemplateBinding ErrorStr}" Name="TextBlockError" VerticalAlignment="Bottom" Margin="9,0,0,4" Foreground="{DynamicResource DangerBrush}" />
-			<ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxWatermarkToggleButton}" />
+			<ToggleButton Grid.Column="1" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" Content="{Binding Path=(hc:InfoElement.Placeholder),RelativeSource={RelativeSource TemplatedParent}}" x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource CheckComboBoxWatermarkToggleButton}" />
 			<Border Grid.Column="1" Margin="1,0">
 				<WrapPanel Name="PART_Panel" Margin="3,1,3,4" />
 			</Border>