WPF slider in disabled state after editing template

WPF slider in disabled state after editing template - c#

I used the latest Blend preview to create a style for the slider. When I run the application, the slider is always disabled. As soon as a remove the custom style, it is enabled again. I cannot see why this would be happening.
Template code generated by Blend is below:
<Style x:Key="SliderStyle1" TargetType="Slider">
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Maximum" Value="10"/>
<Setter Property="Minimum" Value="0"/>
<Setter Property="Value" Value="0"/>
<Setter Property="BorderBrush">
<Setter.Value>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FFA3AEB9" Offset="0"/>
<GradientStop Color="#FF8399A9" Offset="0.375"/>
<GradientStop Color="#FF718597" Offset="0.375"/>
<GradientStop Color="#FF617584" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="IsTabStop" Value="False"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Slider">
<Grid x:Name="Root">
<Grid.Resources>
<ControlTemplate x:Key="RepeatButtonTemplate">
<Grid x:Name="Root" Background="Transparent" Opacity="0"/>
</ControlTemplate>
</Grid.Resources>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver"/>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Duration="0" Storyboard.TargetProperty="Visibility" Storyboard.TargetName="HorizontalTrackRectangleDisabledOverlay">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Duration="0" Storyboard.TargetProperty="Visibility" Storyboard.TargetName="ThumbDisabledOverlay">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Duration="0" Storyboard.TargetProperty="Visibility" Storyboard.TargetName="VerticalTrackRectangleDisabledOverlay">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<Visibility>Visible</Visibility>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid x:Name="HorizontalTemplate" Background="{TemplateBinding Background}">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Rectangle x:Name="TrackRectangle" Grid.ColumnSpan="3" Grid.Column="0" Fill="#FFE6EFF7" Height="3" Margin="5,0,5,0" RadiusY="1" RadiusX="1" Stroke="#FFA3AEB9" StrokeThickness="{TemplateBinding BorderThickness}"/>
<Rectangle x:Name="HorizontalTrackRectangleDisabledOverlay" Grid.ColumnSpan="3" Grid.Column="0" Fill="White" Height="3" Margin="5,0,5,0" Opacity=".55" RadiusY="1" RadiusX="1" Visibility="Collapsed"/>
<RepeatButton x:Name="HorizontalTrackLargeChangeDecreaseRepeatButton" Grid.Column="0" Height="18" IsTabStop="False" Template="{StaticResource RepeatButtonTemplate}"/>
<Thumb x:Name="HorizontalThumb" Grid.Column="1" Height="18" IsTabStop="True" Width="11"/>
<Rectangle x:Name="ThumbDisabledOverlay" Grid.Column="1" Fill="White" Opacity=".55" RadiusY="2" RadiusX="2" Visibility="Collapsed" Width="11"/>
<RepeatButton x:Name="HorizontalTrackLargeChangeIncreaseRepeatButton" Grid.Column="2" Height="18" IsTabStop="False" Template="{StaticResource RepeatButtonTemplate}"/>
</Grid>
<Grid x:Name="VerticalTemplate" Background="{TemplateBinding Background}" Visibility="Collapsed">
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Rectangle Fill="#FFE6EFF7" Margin="0,5,0,5" RadiusY="1" Grid.Row="0" RadiusX="1" Grid.RowSpan="3" Stroke="#FFA3AEB9" StrokeThickness="{TemplateBinding BorderThickness}" Width="3"/>
<Rectangle x:Name="VerticalTrackRectangleDisabledOverlay" Fill="White" Margin="0,5,0,5" Opacity=".55" RadiusY="1" Grid.Row="0" RadiusX="1" Grid.RowSpan="3" Visibility="Collapsed" Width="3"/>
<RepeatButton x:Name="VerticalTrackLargeChangeDecreaseRepeatButton" IsTabStop="False" Grid.Row="2" Template="{StaticResource RepeatButtonTemplate}" Width="18"/>
<Thumb x:Name="VerticalThumb" Height="11" IsTabStop="True" Grid.Row="1" Width="18"/>
<RepeatButton x:Name="VerticalTrackLargeChangeIncreaseRepeatButton" IsTabStop="False" Grid.Row="0" Template="{StaticResource RepeatButtonTemplate}" Width="18"/>
</Grid>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

Some of the Silverlight control templates work in WPF, while others do not. Slider is one of those controls.

Related

How to hide datepicker icon in wpf C#?

I want to hide the default DatePicker icon:
I need something like:
<DatePicker IconVisibality="False"/>
I tried:
Template="{x:Null}"
but it hides all.
I also tried:
Foreground="{x:Null}"
Does anyone know?

A lighter way would be to create a custom control.
public class CustomDatePicker:DatePicker
{
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
if (Template.FindName("PART_Button", this) is Button button)
{
button.Visibility = System.Windows.Visibility.Hidden;
}
}
}
And then consume it in Xaml
<local:CustomDatePicker />

You need to create a custom template. You could right-click on a DatePicker element in design mode in Visual Studio or in Blend and choose Edit Template->Edit a Copy to copy the default template into your XAML markup, and then remove the Button element named "PART_Button" from it:
<DatePicker>
<DatePicker.Style>
<Style TargetType="{x:Type DatePicker}">
<Setter Property="Foreground" Value="#FF333333"/>
<Setter Property="IsTodayHighlighted" Value="True"/>
<Setter Property="SelectedDateFormat" Value="Short"/>
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="BorderBrush">
<Setter.Value>
<LinearGradientBrush EndPoint=".5,0" StartPoint=".5,1">
<GradientStop Color="#FFA3AEB9" Offset="0"/>
<GradientStop Color="#FF8399A9" Offset="0.375"/>
<GradientStop Color="#FF718597" Offset="0.375"/>
<GradientStop Color="#FF617584" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DatePicker}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="{TemplateBinding Padding}">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="PART_DisabledVisual"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid x:Name="PART_Root" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<Grid.Resources>
<SolidColorBrush x:Key="DisabledBrush" Color="#A5FFFFFF"/>
<ControlTemplate x:Key="DropDownButtonTemplate" TargetType="{x:Type Button}">
<Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="0"/>
<VisualTransition GeneratedDuration="0:0:0.1" To="MouseOver"/>
<VisualTransition GeneratedDuration="0:0:0.1" To="Pressed"/>
</VisualStateGroup.Transitions>
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Duration="0" To="#FF448DCA" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" Storyboard.TargetName="Background"/>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#7FFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#CCFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#F2FFFFFF"/>
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" Storyboard.TargetName="Background">
<SplineColorKeyFrame KeyTime="0" Value="#FF448DCA"/>
</ColorAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="Highlight">
<SplineDoubleKeyFrame KeyTime="0" Value="1"/>
</DoubleAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#EAFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#C6FFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#6BFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[0].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#F4FFFFFF"/>
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid Background="#11FFFFFF" FlowDirection="LeftToRight" HorizontalAlignment="Center" Height="18" Margin="0" VerticalAlignment="Center" Width="19">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="23*"/>
<RowDefinition Height="19*"/>
<RowDefinition Height="19*"/>
<RowDefinition Height="19*"/>
</Grid.RowDefinitions>
<Border x:Name="Highlight" BorderBrush="#FF45D6FA" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius="0,0,1,1" Margin="-1" Opacity="0" Grid.Row="0" Grid.RowSpan="4"/>
<Border x:Name="Background" BorderBrush="#FFFFFFFF" BorderThickness="1" Background="#FF1F3B53" Grid.ColumnSpan="4" CornerRadius=".5" Margin="0,-1,0,0" Opacity="1" Grid.Row="1" Grid.RowSpan="3"/>
<Border x:Name="BackgroundGradient" BorderBrush="#BF000000" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius=".5" Margin="0,-1,0,0" Opacity="1" Grid.Row="1" Grid.RowSpan="3">
<Border.Background>
<LinearGradientBrush EndPoint=".7,1" StartPoint=".7,0">
<GradientStop Color="#FFFFFFFF" Offset="0"/>
<GradientStop Color="#F9FFFFFF" Offset="0.375"/>
<GradientStop Color="#E5FFFFFF" Offset="0.625"/>
<GradientStop Color="#C6FFFFFF" Offset="1"/>
</LinearGradientBrush>
</Border.Background>
</Border>
<Rectangle Grid.ColumnSpan="4" Grid.RowSpan="1" StrokeThickness="1">
<Rectangle.Fill>
<LinearGradientBrush EndPoint="0.3,-1.1" StartPoint="0.46,1.6">
<GradientStop Color="#FF4084BD"/>
<GradientStop Color="#FFAFCFEA" Offset="1"/>
</LinearGradientBrush>
</Rectangle.Fill>
<Rectangle.Stroke>
<LinearGradientBrush EndPoint="0.48,-1" StartPoint="0.48,1.25">
<GradientStop Color="#FF494949"/>
<GradientStop Color="#FF9F9F9F" Offset="1"/>
</LinearGradientBrush>
</Rectangle.Stroke>
</Rectangle>
<Path Grid.ColumnSpan="4" Grid.Column="0" Data="M11.426758,8.4305077 L11.749023,8.4305077 L11.749023,16.331387 L10.674805,16.331387 L10.674805,10.299648 L9.0742188,11.298672 L9.0742188,10.294277 C9.4788408,10.090176 9.9094238,9.8090878 10.365967,9.4510155 C10.82251,9.0929432 11.176106,8.7527733 11.426758,8.4305077 z M14.65086,8.4305077 L18.566387,8.4305077 L18.566387,9.3435936 L15.671368,9.3435936 L15.671368,11.255703 C15.936341,11.058764 16.27293,10.960293 16.681133,10.960293 C17.411602,10.960293 17.969301,11.178717 18.354229,11.615566 C18.739157,12.052416 18.931622,12.673672 18.931622,13.479336 C18.931622,15.452317 18.052553,16.438808 16.294415,16.438808 C15.560365,16.438808 14.951641,16.234707 14.468243,15.826504 L14.881817,14.929531 C15.368796,15.326992 15.837872,15.525723 16.289043,15.525723 C17.298809,15.525723 17.803692,14.895514 17.803692,13.635098 C17.803692,12.460618 17.305971,11.873379 16.310528,11.873379 C15.83071,11.873379 15.399232,12.079271 15.016094,12.491055 L14.65086,12.238613 z" Fill="#FF2F2F2F" HorizontalAlignment="Center" Margin="4,3,4,3" Grid.Row="1" Grid.RowSpan="3" RenderTransformOrigin="0.5,0.5" Stretch="Fill" VerticalAlignment="Center"/>
<Ellipse Grid.ColumnSpan="4" Fill="#FFFFFFFF" HorizontalAlignment="Center" Height="3" StrokeThickness="0" VerticalAlignment="Center" Width="3"/>
<Border x:Name="DisabledVisual" BorderBrush="#B2FFFFFF" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius="0,0,.5,.5" Opacity="0" Grid.Row="0" Grid.RowSpan="4"/>
</Grid>
</Grid>
</ControlTemplate>
</Grid.Resources>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<!--<Button x:Name="PART_Button" Grid.Column="1" Foreground="{TemplateBinding Foreground}" Focusable="False" HorizontalAlignment="Left" Margin="3,0,3,0" Grid.Row="0" Template="{StaticResource DropDownButtonTemplate}" VerticalAlignment="Top" Width="20"/>-->
<DatePickerTextBox x:Name="PART_TextBox" Grid.Column="0" Focusable="{TemplateBinding Focusable}" HorizontalContentAlignment="Stretch" Grid.Row="0" VerticalContentAlignment="Stretch"/>
<Grid x:Name="PART_DisabledVisual" Grid.ColumnSpan="2" Grid.Column="0" IsHitTestVisible="False" Opacity="0" Grid.Row="0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Rectangle Grid.Column="0" Fill="#A5FFFFFF" RadiusY="1" Grid.Row="0" RadiusX="1"/>
<Rectangle Grid.Column="1" Fill="#A5FFFFFF" Height="18" Margin="3,0,3,0" RadiusY="1" Grid.Row="0" RadiusX="1" Width="19"/>
<Popup x:Name="PART_Popup" AllowsTransparency="True" Placement="Bottom" PlacementTarget="{Binding ElementName=PART_TextBox}" StaysOpen="False"/>
</Grid>
</Grid>
</Border>
<ControlTemplate.Triggers>
<DataTrigger Binding="{Binding Source={x:Static SystemParameters.HighContrast}}" Value="false">
<Setter Property="Foreground" TargetName="PART_TextBox" Value="{Binding Foreground, RelativeSource={RelativeSource TemplatedParent}}"/>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</DatePicker.Style>
</DatePicker>

Just override your template with another style (like this) and reference it with StaticResource to your DatePicker.
<Style x:Key="WithoutButtonPickerStyle" TargetType="{x:Type DatePicker}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DatePicker}">
<Grid x:Name="PART_Root" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
<DatePickerTextBox x:Name="PART_TextBox">...</DatePickerTextBox>
<Button x:Name="PART_Button" Visibility="Hidden"/>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

<Window.Resources>
<Style x:Key="DatePickerStyle" TargetType="{x:Type DatePicker}">
<Setter Property="Foreground" Value="#FF333333"/>
<Setter Property="IsTodayHighlighted" Value="True"/>
<Setter Property="SelectedDateFormat" Value="Short"/>
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="BorderBrush">
<Setter.Value>
<LinearGradientBrush EndPoint=".5,0" StartPoint=".5,1">
<GradientStop Color="#FFA3AEB9" Offset="0"/>
<GradientStop Color="#FF8399A9" Offset="0.375"/>
<GradientStop Color="#FF718597" Offset="0.375"/>
<GradientStop Color="#FF617584" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DatePicker}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="{TemplateBinding Padding}">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="PART_DisabledVisual"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid x:Name="PART_Root" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<Grid.Resources>
<SolidColorBrush x:Key="DisabledBrush" Color="#A5FFFFFF"/>
<ControlTemplate x:Key="DropDownButtonTemplate" TargetType="{x:Type Button}">
<Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="0"/>
<VisualTransition GeneratedDuration="0:0:0.1" To="MouseOver"/>
<VisualTransition GeneratedDuration="0:0:0.1" To="Pressed"/>
</VisualStateGroup.Transitions>
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Duration="0" To="#FF448DCA" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" Storyboard.TargetName="Background"/>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#7FFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#CCFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#F2FFFFFF"/>
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" Storyboard.TargetName="Background">
<SplineColorKeyFrame KeyTime="0" Value="#FF448DCA"/>
</ColorAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="Highlight">
<SplineDoubleKeyFrame KeyTime="0" Value="1"/>
</DoubleAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#EAFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#C6FFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#6BFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[0].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#F4FFFFFF"/>
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid Background="#11FFFFFF" FlowDirection="LeftToRight" HorizontalAlignment="Center" Height="18" Margin="0" VerticalAlignment="Center" Width="19">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="23*"/>
<RowDefinition Height="19*"/>
<RowDefinition Height="19*"/>
<RowDefinition Height="19*"/>
</Grid.RowDefinitions>
<Border x:Name="Highlight" BorderBrush="#FF45D6FA" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius="0,0,1,1" Margin="-1" Opacity="0" Grid.Row="0" Grid.RowSpan="4"/>
<Border x:Name="Background" BorderBrush="#FFFFFFFF" BorderThickness="1" Background="#FF1F3B53" Grid.ColumnSpan="4" CornerRadius=".5" Margin="0,-1,0,0" Opacity="1" Grid.Row="1" Grid.RowSpan="3"/>
<Border x:Name="BackgroundGradient" BorderBrush="#BF000000" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius=".5" Margin="0,-1,0,0" Opacity="1" Grid.Row="1" Grid.RowSpan="3">
<Border.Background>
<LinearGradientBrush EndPoint=".7,1" StartPoint=".7,0">
<GradientStop Color="#FFFFFFFF" Offset="0"/>
<GradientStop Color="#F9FFFFFF" Offset="0.375"/>
<GradientStop Color="#E5FFFFFF" Offset="0.625"/>
<GradientStop Color="#C6FFFFFF" Offset="1"/>
</LinearGradientBrush>
</Border.Background>
</Border>
<Rectangle Grid.ColumnSpan="4" Grid.RowSpan="1" StrokeThickness="1">
<Rectangle.Fill>
<LinearGradientBrush EndPoint="0.3,-1.1" StartPoint="0.46,1.6">
<GradientStop Color="#FF4084BD"/>
<GradientStop Color="#FFAFCFEA" Offset="1"/>
</LinearGradientBrush>
</Rectangle.Fill>
<Rectangle.Stroke>
<LinearGradientBrush EndPoint="0.48,-1" StartPoint="0.48,1.25">
<GradientStop Color="#FF494949"/>
<GradientStop Color="#FF9F9F9F" Offset="1"/>
</LinearGradientBrush>
</Rectangle.Stroke>
</Rectangle>
<Path Grid.ColumnSpan="4" Grid.Column="0" Data="M11.426758,8.4305077 L11.749023,8.4305077 L11.749023,16.331387 L10.674805,16.331387 L10.674805,10.299648 L9.0742188,11.298672 L9.0742188,10.294277 C9.4788408,10.090176 9.9094238,9.8090878 10.365967,9.4510155 C10.82251,9.0929432 11.176106,8.7527733 11.426758,8.4305077 z M14.65086,8.4305077 L18.566387,8.4305077 L18.566387,9.3435936 L15.671368,9.3435936 L15.671368,11.255703 C15.936341,11.058764 16.27293,10.960293 16.681133,10.960293 C17.411602,10.960293 17.969301,11.178717 18.354229,11.615566 C18.739157,12.052416 18.931622,12.673672 18.931622,13.479336 C18.931622,15.452317 18.052553,16.438808 16.294415,16.438808 C15.560365,16.438808 14.951641,16.234707 14.468243,15.826504 L14.881817,14.929531 C15.368796,15.326992 15.837872,15.525723 16.289043,15.525723 C17.298809,15.525723 17.803692,14.895514 17.803692,13.635098 C17.803692,12.460618 17.305971,11.873379 16.310528,11.873379 C15.83071,11.873379 15.399232,12.079271 15.016094,12.491055 L14.65086,12.238613 z" Fill="#FF2F2F2F" HorizontalAlignment="Center" Margin="4,3,4,3" Grid.Row="1" Grid.RowSpan="3" RenderTransformOrigin="0.5,0.5" Stretch="Fill" VerticalAlignment="Center"/>
<Ellipse Grid.ColumnSpan="4" Fill="#FFFFFFFF" HorizontalAlignment="Center" Height="3" StrokeThickness="0" VerticalAlignment="Center" Width="3"/>
<Border x:Name="DisabledVisual" BorderBrush="#B2FFFFFF" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius="0,0,.5,.5" Opacity="0" Grid.Row="0" Grid.RowSpan="4"/>
</Grid>
</Grid>
</ControlTemplate>
</Grid.Resources>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<!--This is Button Templete-->
<Button x:Name="PART_Button" Grid.Column="1" Foreground="{TemplateBinding Foreground}" Focusable="False" HorizontalAlignment="Left" Margin="3,0,3,0" Grid.Row="0" VerticalAlignment="Top" Width="20"/>
<!--...-->
<DatePickerTextBox x:Name="PART_TextBox" Grid.Column="0" Foreground="{TemplateBinding Foreground}" Focusable="{TemplateBinding Focusable}" HorizontalContentAlignment="Stretch" Grid.Row="0" VerticalContentAlignment="Stretch"/>
<Grid x:Name="PART_DisabledVisual" Grid.ColumnSpan="2" Grid.Column="0" IsHitTestVisible="False" Opacity="0" Grid.Row="0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Rectangle Grid.Column="0" Fill="#A5FFFFFF" RadiusY="1" Grid.Row="0" RadiusX="1"/>
<Rectangle Grid.Column="1" Fill="#A5FFFFFF" Height="18" Margin="3,0,3,0" RadiusY="1" Grid.Row="0" RadiusX="1" Width="19"/>
<Popup x:Name="PART_Popup" AllowsTransparency="True" Placement="Bottom" PlacementTarget="{Binding ElementName=PART_TextBox}" StaysOpen="False"/>
</Grid>
</Grid>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid>
<DatePicker Width="150" Height="26" Style="{StaticResource DatePickerStyle}"/>
</Grid>

WPF DatePicker Icon Size

I have a DatePicker like this:
<DatePicker Grid.Row="7" HorizontalAlignment="Left" FontSize="43" CalendarStyle="{StaticResource styleCalendar}"/>
The problem is, that increasing the font size of the date picker doesn't resize the icon and it remains small.
I've searched but couldn't find a proper way to only resize the icon, or maybe this is not the proper way of enlarging the whold picker

For people who are not satisfied with the simple answers from Michael Repucci there is a "cleaner" alternative solution to my taste which allows you to surround only the icon by a viewbox.
You can right click on the element you want to modify on the Design panel of an xaml file and click on "modify model". This will take you to the xaml code of the element. Then you have to locate the part you want to modify. Here I have surrounded only the Button that contains the icon with a ViewBox and not the whole control.
The part in question is almost at the bottom. I put some line feeds to make it more visible.
<Style x:Key="DatePickerIconResizingStyle" TargetType="{x:Type DatePicker}">
<Setter Property="Foreground" Value="#FF333333"/>
<Setter Property="IsTodayHighlighted" Value="True"/>
<Setter Property="SelectedDateFormat" Value="Short"/>
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="BorderBrush">
<Setter.Value>
<LinearGradientBrush EndPoint=".5,0" StartPoint=".5,1">
<GradientStop Color="#FFA3AEB9" Offset="0"/>
<GradientStop Color="#FF8399A9" Offset="0.375"/>
<GradientStop Color="#FF718597" Offset="0.375"/>
<GradientStop Color="#FF617584" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DatePicker}">
<Border Background="{TemplateBinding Background}" BorderThickness="{TemplateBinding BorderThickness}" BorderBrush="{TemplateBinding BorderBrush}" Padding="{TemplateBinding Padding}">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0" Storyboard.TargetName="PART_DisabledVisual" Storyboard.TargetProperty="Opacity" To="1"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid x:Name="PART_Root" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<Grid.Resources>
<SolidColorBrush x:Key="DisabledBrush" Color="#A5FFFFFF"/>
<ControlTemplate x:Key="DropDownButtonTemplate" TargetType="{x:Type Button}">
<Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="0"/>
<VisualTransition GeneratedDuration="0:0:0.1" To="MouseOver"/>
<VisualTransition GeneratedDuration="0:0:0.1" To="Pressed"/>
</VisualStateGroup.Transitions>
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Duration="0" Storyboard.TargetName="Background" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" To="#FF448DCA"/>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)">
<SplineColorKeyFrame KeyTime="0" Value="#7FFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)">
<SplineColorKeyFrame KeyTime="0" Value="#CCFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)">
<SplineColorKeyFrame KeyTime="0" Value="#F2FFFFFF"/>
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="Background" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)">
<SplineColorKeyFrame KeyTime="0" Value="#FF448DCA"/>
</ColorAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="Highlight" Storyboard.TargetProperty="(UIElement.Opacity)">
<SplineDoubleKeyFrame KeyTime="0" Value="1"/>
</DoubleAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)">
<SplineColorKeyFrame KeyTime="0" Value="#EAFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)">
<SplineColorKeyFrame KeyTime="0" Value="#C6FFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)">
<SplineColorKeyFrame KeyTime="0" Value="#6BFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[0].(GradientStop.Color)">
<SplineColorKeyFrame KeyTime="0" Value="#F4FFFFFF"/>
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid Background="#11FFFFFF" FlowDirection="LeftToRight" HorizontalAlignment="Center" Height="18" Margin="0" VerticalAlignment="Center" Width="19">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="23*"/>
<RowDefinition Height="19*"/>
<RowDefinition Height="19*"/>
<RowDefinition Height="19*"/>
</Grid.RowDefinitions>
<Border x:Name="Highlight" BorderThickness="1" BorderBrush="#FF45D6FA" CornerRadius="0,0,1,1" Grid.ColumnSpan="4" Margin="-1" Opacity="0" Grid.RowSpan="4" Grid.Row="0"/>
<Border x:Name="Background" Background="#FF1F3B53" BorderThickness="1" BorderBrush="#FFFFFFFF" CornerRadius=".5" Grid.ColumnSpan="4" Margin="0,-1,0,0" Opacity="1" Grid.RowSpan="3" Grid.Row="1"/>
<Border x:Name="BackgroundGradient" BorderThickness="1" BorderBrush="#BF000000" CornerRadius=".5" Grid.ColumnSpan="4" Margin="0,-1,0,0" Opacity="1" Grid.RowSpan="3" Grid.Row="1">
<Border.Background>
<LinearGradientBrush EndPoint=".7,1" StartPoint=".7,0">
<GradientStop Color="#FFFFFFFF" Offset="0"/>
<GradientStop Color="#F9FFFFFF" Offset="0.375"/>
<GradientStop Color="#E5FFFFFF" Offset="0.625"/>
<GradientStop Color="#C6FFFFFF" Offset="1"/>
</LinearGradientBrush>
</Border.Background>
</Border>
<Rectangle Grid.ColumnSpan="4" Grid.RowSpan="1" StrokeThickness="1">
<Rectangle.Fill>
<LinearGradientBrush EndPoint="0.3,-1.1" StartPoint="0.46,1.6">
<GradientStop Color="#FF4084BD"/>
<GradientStop Color="#FFAFCFEA" Offset="1"/>
</LinearGradientBrush>
</Rectangle.Fill>
<Rectangle.Stroke>
<LinearGradientBrush EndPoint="0.48,-1" StartPoint="0.48,1.25">
<GradientStop Color="#FF494949"/>
<GradientStop Color="#FF9F9F9F" Offset="1"/>
</LinearGradientBrush>
</Rectangle.Stroke>
</Rectangle>
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<Ellipse Grid.ColumnSpan="4" Fill="#FFFFFFFF" HorizontalAlignment="Center" Height="3" StrokeThickness="0" VerticalAlignment="Center" Width="3"/>
<Border x:Name="DisabledVisual" BorderThickness="1" BorderBrush="#B2FFFFFF" CornerRadius="0,0,.5,.5" Grid.ColumnSpan="4" Opacity="0" Grid.RowSpan="4" Grid.Row="0"/>
</Grid>
</Grid>
</ControlTemplate>
</Grid.Resources>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<!-- This ViewBox allows to resize the icon automatically to fill the full height of the DatePicker -->
<Viewbox Grid.Column="1" HorizontalAlignment="Left" Margin="3,0,3,0" Grid.Row="0" VerticalAlignment="Top">
<Button x:Name="PART_Button" Focusable="False" Foreground="{TemplateBinding Foreground}" Template="{StaticResource DropDownButtonTemplate}" />
</Viewbox>
<DatePickerTextBox x:Name="PART_TextBox" Grid.Column="0" Focusable="{TemplateBinding Focusable}" HorizontalContentAlignment="Stretch" Grid.Row="0" VerticalContentAlignment="Stretch"/>
<Grid x:Name="PART_DisabledVisual" Grid.ColumnSpan="2" Grid.Column="0" IsHitTestVisible="False" Opacity="0" Grid.Row="0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Rectangle Grid.Column="0" Fill="#A5FFFFFF" RadiusX="1" RadiusY="1" Grid.Row="0"/>
<Rectangle Grid.Column="1" Fill="#A5FFFFFF" Height="18" Margin="3,0,3,0" RadiusX="1" RadiusY="1" Grid.Row="0" Width="19"/>
<Popup x:Name="PART_Popup" AllowsTransparency="True" Placement="Bottom" PlacementTarget="{Binding ElementName=PART_TextBox}" StaysOpen="False"/>
</Grid>
</Grid>
</Border>
<ControlTemplate.Triggers>
<DataTrigger Binding="{Binding Source={x:Static SystemParameters.HighContrast}}" Value="false">
<Setter Property="Foreground" TargetName="PART_TextBox" Value="{Binding Foreground, RelativeSource={RelativeSource TemplatedParent}}"/>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
I hope this answer will help someone.

The easiest way to do this is to put the DatePicker into a Viewbox and adjust the size of the Viewbox. So borrowing from your example, you might have
<Viewbox Grid.Row="7" HorizontalAlignment="Left" Width="150">
<DatePicker CalendarStyle="{StaticResource styleCalendar}"/>
</Viewbox>
where increasing/decreasing the Viewbox.Width parameter will allow you to adjust the size of the DatePicker.

For me the solution that worked was to put only the calendar button inside a viewbox.
<DatePicker...>
<DatePicker.Resources>
<Style TargetType="{x:Type Button}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Button}">
<Viewbox>
<ContentPresenter/>
</Viewbox>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</DatePicker.Resources>
</DatePicker>

ExtendedToolkit DatePicker Calendar FontSize

I am using the ExtendedToolkit for WPF C#. Specifically I am using the DateTimePicker, I have tried changing the font size for this element however it does not change the size of the attached calendar that you use to select the date;
Is there a way to change it's FontSize in the ExtendedToolkit so it appears larger?

I have the requirement for Calendar control to display larger numbers and since DateTimePicker uses Calendar, the same solution applies here.
Calendar has CalendarDayButtonStyle property for customizing date fields. The only property to change is CalendarDayButton.FontSize:
<xctk:DateTimePicker VerticalAlignment="Top">
<xctk:DateTimePicker.Resources>
<Style TargetType="Calendar">
<Setter Property="CalendarDayButtonStyle">
<Setter.Value>
<Style TargetType="CalendarDayButton"
BasedOn="{StaticResource {x:Type CalendarDayButton}}">
<Setter Property="FontSize" Value="16"/>
</Style>
</Setter.Value>
</Setter>
</Style>
</xctk:DateTimePicker.Resources>
</xctk:DateTimePicker>

You can generate a copy of template and style for Calendar and CalendarItem through Blend tool and override the default FontSize. The copy I have generated through Blend is :
<Style x:Key="CalendarStyle1" TargetType="{x:Type Calendar}">
<Setter Property="Foreground" Value="#FF333333"/>
<Setter Property="Background">
<Setter.Value>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FFE4EAF0" Offset="0"/>
<GradientStop Color="#FFECF0F4" Offset="0.16"/>
<GradientStop Color="#FFFCFCFD" Offset="0.16"/>
<GradientStop Color="#FFFFFFFF" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="BorderBrush">
<Setter.Value>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FFA3AEB9" Offset="0"/>
<GradientStop Color="#FF8399A9" Offset="0.375"/>
<GradientStop Color="#FF718597" Offset="0.375"/>
<GradientStop Color="#FF617584" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Calendar}">
<StackPanel x:Name="PART_Root" HorizontalAlignment="Center">
<CalendarItem x:Name="PART_CalendarItem" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Style="{DynamicResource CalendarItemStyle1}"/>
</StackPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="CalendarItemStyle1" TargetType="{x:Type CalendarItem}">
<Setter Property="Margin" Value="0,3,0,3"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type CalendarItem}">
<ControlTemplate.Resources>
<DataTemplate x:Key="{x:Static CalendarItem.DayTitleTemplateResourceKey}">
<TextBlock Foreground="#FF333333" FontWeight="Bold" FontSize="9.5" FontFamily="Verdana" HorizontalAlignment="Center" Margin="0,6,0,6" Text="{Binding}" VerticalAlignment="Center"/>
</DataTemplate>
</ControlTemplate.Resources>
<Grid x:Name="PART_Root">
<Grid.Resources>
<SolidColorBrush x:Key="DisabledColor" Color="#A5FFFFFF"/>
</Grid.Resources>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="PART_DisabledVisual"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" CornerRadius="1">
<Border BorderBrush="#FFFFFFFF" BorderThickness="2" CornerRadius="1">
<Grid>
<Grid.Resources>
<ControlTemplate x:Key="PreviousButtonTemplate" TargetType="{x:Type Button}">
<Grid Cursor="Hand">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Duration="0" To="#FF73A9D8" Storyboard.TargetProperty="(Shape.Fill).(SolidColorBrush.Color)" Storyboard.TargetName="path"/>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0" To=".5" Storyboard.TargetProperty="(Shape.Fill).(Brush.Opacity)" Storyboard.TargetName="path"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Rectangle Fill="#11E5EBF1" Opacity="1" Stretch="Fill"/>
<Grid>
<Path x:Name="path" Data="M288.75,232.25 L288.75,240.625 L283,236.625 z" Fill="#FF333333" HorizontalAlignment="Left" Height="10" Margin="14,-6,0,0" Stretch="Fill" VerticalAlignment="Center" Width="6"/>
</Grid>
</Grid>
</ControlTemplate>
<ControlTemplate x:Key="NextButtonTemplate" TargetType="{x:Type Button}">
<Grid Cursor="Hand">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Duration="0" To="#FF73A9D8" Storyboard.TargetProperty="(Shape.Fill).(SolidColorBrush.Color)" Storyboard.TargetName="path"/>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0" To=".5" Storyboard.TargetProperty="(Shape.Fill).(Brush.Opacity)" Storyboard.TargetName="path"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Rectangle Fill="#11E5EBF1" Opacity="1" Stretch="Fill"/>
<Grid>
<Path x:Name="path" Data="M282.875,231.875 L282.875,240.375 L288.625,236 z" Fill="#FF333333" HorizontalAlignment="Right" Height="10" Margin="0,-6,14,0" Stretch="Fill" VerticalAlignment="Center" Width="6"/>
</Grid>
</Grid>
</ControlTemplate>
<ControlTemplate x:Key="HeaderButtonTemplate" TargetType="{x:Type Button}">
<Grid Cursor="Hand">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Duration="0" To="#FF73A9D8" Storyboard.TargetProperty="(TextElement.Foreground).(SolidColorBrush.Color)" Storyboard.TargetName="buttonContent"/>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0" To=".5" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="buttonContent"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<ContentPresenter x:Name="buttonContent" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" TextElement.Foreground="#FF333333" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="1,4,1,9" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Grid>
</ControlTemplate>
</Grid.Resources>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Button x:Name="PART_PreviousButton" Grid.Column="0" Focusable="False" HorizontalAlignment="Left" Height="20" Grid.Row="0" Template="{StaticResource PreviousButtonTemplate}" Width="28"/>
<Button x:Name="PART_HeaderButton" Grid.Column="1" FontWeight="Bold" Focusable="False" FontSize="10.5" HorizontalAlignment="Center" Grid.Row="0" Template="{StaticResource HeaderButtonTemplate}" Height="100" VerticalAlignment="Center"/>
<Button x:Name="PART_NextButton" Grid.Column="2" Focusable="False" HorizontalAlignment="Right" Height="20" Grid.Row="0" Template="{StaticResource NextButtonTemplate}" Width="28"/>
<Grid x:Name="PART_MonthView" Grid.ColumnSpan="3" HorizontalAlignment="Center" Margin="6,-1,6,6" Grid.Row="1" Visibility="Visible">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
</Grid>
<Grid x:Name="PART_YearView" Grid.ColumnSpan="3" HorizontalAlignment="Center" Margin="6,-3,7,6" Grid.Row="1" Visibility="Hidden">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
</Grid>
</Grid>
</Border>
</Border>
<Rectangle x:Name="PART_DisabledVisual" Fill="{StaticResource DisabledColor}" Opacity="0" RadiusY="2" RadiusX="2" Stretch="Fill" Stroke="{StaticResource DisabledColor}" StrokeThickness="1" Visibility="Collapsed"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Visibility" TargetName="PART_DisabledVisual" Value="Visible"/>
</Trigger>
<DataTrigger Binding="{Binding DisplayMode, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Calendar}}}" Value="Year">
<Setter Property="Visibility" TargetName="PART_MonthView" Value="Hidden"/>
<Setter Property="Visibility" TargetName="PART_YearView" Value="Visible"/>
</DataTrigger>
<DataTrigger Binding="{Binding DisplayMode, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Calendar}}}" Value="Decade">
<Setter Property="Visibility" TargetName="PART_MonthView" Value="Hidden"/>
<Setter Property="Visibility" TargetName="PART_YearView" Value="Visible"/>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

Try This.
Step 1 :
Create a Style for a Calender
<Style x:Key="styleCalendar" TargetType="{x:Type Calendar}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Calendar}">
<!-- Wrapping in ViewBox will enlarge calendar of that size.-->
<Viewbox Height="400"
Width="400">
<CalendarItem x:Name="CalendarItem"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"/>
</Viewbox>
</ControlTemplate>
</Setter.Value>
</Setter>
Step 2 :
Apply Style for your DatePicker.
<DatePicker CalendarStyle="{StaticResource styleCalendar}"
Height="25" HorizontalAlignment="Left" Name="datePicker1" Width="120" />

WPF DatePicker format

I got this sample code from this forum.
<DatePicker SelectedDate="{Binding myVideModelProperty}"
Height="25" HorizontalAlignment="Left" Margin="81,-2,0,0" Name="myDatePicker" VerticalAlignment="Top" Width="115">
<DatePicker.Resources>
<Style TargetType="{x:Type DatePickerTextBox}">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<TextBox x:Name="PART_TextBox"
Text="{Binding Path=SelectedDate, RelativeSource={RelativeSource AncestorType={x:Type DatePicker}}, StringFormat={}{0:yyyy/MM/dd}}" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</DatePicker.Resources>
</DatePicker>
But I want the format i.e yyyy/MM/dd to come from an application property called dateformat.
Can you help me put the stringformat as a binding to the application property.

All of the other answers seem a little bit convoluted. It is as simple as:
<DatePicker SelectedDate="{Binding PropertyName, StringFormat=dd/MM/yyyy}"/>
All you need to do is adjust the string format to suit yourself.

Use this snippet for your DatePicker (you will have to style it):
<DatePicker SelectedDate="{Binding myVideModelProperty}">
<DatePicker.Resources>
<Style TargetType="{x:Type DatePickerTextBox}">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<TextBox x:Name="PART_TextBox"
Text="{Binding Path=SelectedDate,
RelativeSource={RelativeSource AncestorType={x:Type DatePicker}},
StringFormat={x:Static local:App.DateFormat}}" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</DatePicker.Resources>
</DatePicker>
Use this snippet for your App.xaml.cs (change the namespace to something useful):
namespace _24417730
{
public partial class App
{
public static string DateFormat = "yyyy/MM/dd";
}
}
In the xaml control containing your DatePicker, define a XAML namespace like so:
xmlns:local="clr-namespace:_24417730"
Note that you will have to change the namespace to the one you used to define your application class.
Here is how I defined my xaml namespace on the MainWindow.xaml control:
<Window x:Class="_24417730.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:_24417730"
Title="MainWindow" Height="350" Width="525">
<StackPanel>
<DatePicker SelectedDate="{Binding myVideModelProperty}">
<DatePicker.Resources>
<Style TargetType="{x:Type DatePickerTextBox}">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<TextBox x:Name="PART_TextBox"
Text="{Binding Path=SelectedDate,
RelativeSource={RelativeSource AncestorType={x:Type DatePicker}},
StringFormat={x:Static local:App.DateFormat}}" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</DatePicker.Resources>
</DatePicker>
</StackPanel>
</Window>
Also, reading up on Static Markup Extension and XAML Namespaces may help for future reference.
If you require any further clarifications, I will be happy to assist.

You can use converters for that.
Or you can add another property to your class which will return the formatted date.
With converter
public class DateFormatConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
return string.Format(Application.DateFormat, value);
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
}
}

<Style TargetType="{x:Type DatePicker}">
<Setter Property="Foreground" Value="#FF333333"/>
<Setter Property="IsTodayHighlighted" Value="True"/>
<Setter Property="SelectedDateFormat" Value="Short"/>
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="BorderBrush">
<Setter.Value>
<LinearGradientBrush EndPoint=".5,0" StartPoint=".5,1">
<GradientStop Color="#FFA3AEB9" Offset="0"/>
<GradientStop Color="#FF8399A9" Offset="0.375"/>
<GradientStop Color="#FF718597" Offset="0.375"/>
<GradientStop Color="#FF617584" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DatePicker}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="{TemplateBinding Padding}">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="PART_DisabledVisual"/>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid x:Name="PART_Root" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<Grid.Resources>
<SolidColorBrush x:Key="DisabledBrush" Color="#A5FFFFFF"/>
<ControlTemplate x:Key="DropDownButtonTemplate" TargetType="{x:Type Button}">
<Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualStateGroup.Transitions>
<VisualTransition GeneratedDuration="0"/>
<VisualTransition GeneratedDuration="0:0:0.1" To="MouseOver"/>
<VisualTransition GeneratedDuration="0:0:0.1" To="Pressed"/>
</VisualStateGroup.Transitions>
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Duration="0" To="#FF448DCA" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" Storyboard.TargetName="Background"/>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#7FFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#CCFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#F2FFFFFF"/>
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)" Storyboard.TargetName="Background">
<SplineColorKeyFrame KeyTime="0" Value="#FF448DCA"/>
</ColorAnimationUsingKeyFrames>
<DoubleAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="Highlight">
<SplineDoubleKeyFrame KeyTime="0" Value="1"/>
</DoubleAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#EAFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[2].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#C6FFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[3].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#6BFFFFFF"/>
</ColorAnimationUsingKeyFrames>
<ColorAnimationUsingKeyFrames BeginTime="0" Duration="00:00:00.001" Storyboard.TargetProperty="(Border.Background).(GradientBrush.GradientStops)[0].(GradientStop.Color)" Storyboard.TargetName="BackgroundGradient">
<SplineColorKeyFrame KeyTime="0" Value="#F4FFFFFF"/>
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Grid Background="#11FFFFFF" FlowDirection="LeftToRight" HorizontalAlignment="Center" Height="18" Margin="0" VerticalAlignment="Center" Width="19">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
<ColumnDefinition Width="20*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="23*"/>
<RowDefinition Height="19*"/>
<RowDefinition Height="19*"/>
<RowDefinition Height="19*"/>
</Grid.RowDefinitions>
<Border x:Name="Highlight" BorderBrush="#FF45D6FA" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius="0,0,1,1" Margin="-1" Opacity="0" Grid.Row="0" Grid.RowSpan="4"/>
<Border x:Name="Background" BorderBrush="#FFFFFFFF" BorderThickness="1" Background="#FF1F3B53" Grid.ColumnSpan="4" CornerRadius=".5" Margin="0,-1,0,0" Opacity="1" Grid.Row="1" Grid.RowSpan="3"/>
<Border x:Name="BackgroundGradient" BorderBrush="#BF000000" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius=".5" Margin="0,-1,0,0" Opacity="1" Grid.Row="1" Grid.RowSpan="3">
<Border.Background>
<LinearGradientBrush EndPoint=".7,1" StartPoint=".7,0">
<GradientStop Color="#FFFFFFFF" Offset="0"/>
<GradientStop Color="#F9FFFFFF" Offset="0.375"/>
<GradientStop Color="#E5FFFFFF" Offset="0.625"/>
<GradientStop Color="#C6FFFFFF" Offset="1"/>
</LinearGradientBrush>
</Border.Background>
</Border>
<Rectangle Grid.ColumnSpan="4" Grid.RowSpan="1" StrokeThickness="1">
<Rectangle.Fill>
<LinearGradientBrush EndPoint="0.3,-1.1" StartPoint="0.46,1.6">
<GradientStop Color="#FF4084BD"/>
<GradientStop Color="#FFAFCFEA" Offset="1"/>
</LinearGradientBrush>
</Rectangle.Fill>
<Rectangle.Stroke>
<LinearGradientBrush EndPoint="0.48,-1" StartPoint="0.48,1.25">
<GradientStop Color="#FF494949"/>
<GradientStop Color="#FF9F9F9F" Offset="1"/>
</LinearGradientBrush>
</Rectangle.Stroke>
</Rectangle>
<Path Grid.ColumnSpan="4" Grid.Column="0" Data="M11.426758,8.4305077 L11.749023,8.4305077 L11.749023,16.331387 L10.674805,16.331387 L10.674805,10.299648 L9.0742188,11.298672 L9.0742188,10.294277 C9.4788408,10.090176 9.9094238,9.8090878 10.365967,9.4510155 C10.82251,9.0929432 11.176106,8.7527733 11.426758,8.4305077 z M14.65086,8.4305077 L18.566387,8.4305077 L18.566387,9.3435936 L15.671368,9.3435936 L15.671368,11.255703 C15.936341,11.058764 16.27293,10.960293 16.681133,10.960293 C17.411602,10.960293 17.969301,11.178717 18.354229,11.615566 C18.739157,12.052416 18.931622,12.673672 18.931622,13.479336 C18.931622,15.452317 18.052553,16.438808 16.294415,16.438808 C15.560365,16.438808 14.951641,16.234707 14.468243,15.826504 L14.881817,14.929531 C15.368796,15.326992 15.837872,15.525723 16.289043,15.525723 C17.298809,15.525723 17.803692,14.895514 17.803692,13.635098 C17.803692,12.460618 17.305971,11.873379 16.310528,11.873379 C15.83071,11.873379 15.399232,12.079271 15.016094,12.491055 L14.65086,12.238613 z" Fill="#FF2F2F2F" HorizontalAlignment="Center" Margin="4,3,4,3" Grid.Row="1" Grid.RowSpan="3" RenderTransformOrigin="0.5,0.5" Stretch="Fill" VerticalAlignment="Center"/>
<Ellipse Grid.ColumnSpan="4" Fill="#FFFFFFFF" HorizontalAlignment="Center" Height="3" StrokeThickness="0" VerticalAlignment="Center" Width="3"/>
<Border x:Name="DisabledVisual" BorderBrush="#B2FFFFFF" BorderThickness="1" Grid.ColumnSpan="4" CornerRadius="0,0,.5,.5" Opacity="0" Grid.Row="0" Grid.RowSpan="4"/>
</Grid>
</Grid>
</ControlTemplate>
</Grid.Resources>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Button x:Name="PART_Button" Grid.Column="1" Foreground="{TemplateBinding Foreground}" Focusable="False" HorizontalAlignment="Left" Margin="3,0,3,0" Grid.Row="0" Template="{StaticResource DropDownButtonTemplate}" VerticalAlignment="Top" Width="20"/>
<DatePickerTextBox x:Name="PART_TextBox" Grid.Column="0" Focusable="{TemplateBinding Focusable}" HorizontalContentAlignment="Stretch" Grid.Row="0" VerticalContentAlignment="Stretch" Text="{Binding SelectedDate,RelativeSource={RelativeSource TemplatedParent},StringFormat='dd/MM/yyyy'}" />
<Grid x:Name="PART_DisabledVisual" Grid.ColumnSpan="2" Grid.Column="0" IsHitTestVisible="False" Opacity="0" Grid.Row="0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Rectangle Grid.Column="0" Fill="#A5FFFFFF" RadiusY="1" Grid.Row="0" RadiusX="1"/>
<Rectangle Grid.Column="1" Fill="#A5FFFFFF" Height="18" Margin="3,0,3,0" RadiusY="1" Grid.Row="0" RadiusX="1" Width="19"/>
<Popup x:Name="PART_Popup" AllowsTransparency="True" Placement="Bottom" PlacementTarget="{Binding ElementName=PART_TextBox}" StaysOpen="False"/>
</Grid>
</Grid>
</Border>
<ControlTemplate.Triggers>
<DataTrigger Binding="{Binding Source={x:Static SystemParameters.HighContrast}}" Value="false">
<Setter Property="Foreground" TargetName="PART_TextBox" Value="{Binding Foreground, RelativeSource={RelativeSource TemplatedParent}}"/>
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

Add a Style for DatePickerTextBox like this, no CultureInfo required, make the format you want with StringFormat:
<DatePicker SelectedDate="{Binding myProperty}">
<DatePicker.Resources>
<Style TargetType="{x:Type DatePickerTextBox}">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<TextBox x:Name="PART_TextBox" Text="{Binding Path=SelectedDate, StringFormat='dd MMMM yyyy', RelativeSource={RelativeSource AncestorType={x:Type DatePicker}}}" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</DatePicker.Resources>
</DatePicker>

Most of the time, when you want to change date format, it's usually because your had the wrong culture.
Set the current thread culture correctly :
Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("fr-FR");
After that, if the culture format is still not ok for you, you can change it via ShortDatePattern and LongDatePattern properties of CulureInfo.
ci.DateTimeFormat.ShortDatePattern = "dd/MM/yyyy"; //where ci a CultureInfo object
Finally you can tell DatePicker to prefer Short or Long format via SelectedDateFormat property.

WPF Datepicker Calendar buttons not working (Using modified template)

I apologize in advance if this is already out there (I did an advanced search and couldn't find this specific issue.)
I'm using a custom WPF Datepicker calendar template (Just changing colors really), but now my buttons don't work. It will pop up the calendar, but nothing works from that point, Am i missing anything? Here's the code below:
<ResourceDictionary
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Controls="clr-namespace:Microsoft.Windows.Controls;assembly=WPFToolkit"
xmlns:primitives="clr-namespace:Microsoft.Windows.Controls.Primitives;assembly=WPFToolkit" >
<Style x:Key="CalendarStyle1" TargetType="{x:Type Calendar}">
<Setter Property="Foreground" Value="#FF333333"/>
<Setter Property="Background">
<Setter.Value>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FFE4EAF0" Offset="0"/>
<GradientStop Color="#FFECF0F4" Offset="0.16"/>
<GradientStop Color="#FFFCFCFD" Offset="0.16"/>
<GradientStop Color="White" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="BorderBrush">
<Setter.Value>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FFA3AEB9" Offset="0"/>
<GradientStop Color="#FF8399A9" Offset="0.375"/>
<GradientStop Color="#FF718597" Offset="0.375"/>
<GradientStop Color="#FF617584" Offset="1"/>
</LinearGradientBrush>
</Setter.Value>
</Setter>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Calendar}">
<StackPanel x:Name="PART_Root" HorizontalAlignment="Center">
<primitives:CalendarItem x:Name="PART_CalendarItem" Style="{DynamicResource CalenderStyleNew}" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}"/>
</StackPanel>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="CalenderStyleNew"
TargetType="primitives:CalendarItem">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="primitives:CalendarItem">
<ControlTemplate.Resources>
<!-- Start: Data template for header button -->
<DataTemplate x:Key="DayTitleTemplate">
<TextBlock
FontWeight="Bold"
FontFamily="Verdana"
FontSize="9.5"
Foreground="Black"
HorizontalAlignment="Center"
Text="{Binding}"
Margin="0,6,0,6"
VerticalAlignment="Center"/>
</DataTemplate>
<!-- End: Data template for header button -->
<DataTemplate x:Key="MonthTitleTemplate">
<TextBlock
FontWeight="Medium"
FontFamily="Verdana"
FontSize="9.5"
Foreground="Red"
HorizontalAlignment="Center"
Text="{Binding}"
Margin="0,10,0,6"
VerticalAlignment="Center"/>
</DataTemplate>
</ControlTemplate.Resources>
<Grid Name="PART_Root" >
<Grid.Resources>
<SolidColorBrush x:Key="DisabledColor" Color="#A5FFFFFF" />
</Grid.Resources>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Storyboard.TargetName="PART_DisabledVisual" Storyboard.TargetProperty="Opacity" To="1" Duration="0" />
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Border
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
CornerRadius="1">
<!-- This Brush is new -->
<Border.Background>
<LinearGradientBrush StartPoint="0 0" EndPoint="0 1">
<GradientStop Offset="0" Color="#FFE4EAF0" />
<GradientStop Offset="0.5" Color="#FFECF0F4" />
<GradientStop Offset="1" Color="#FFECF0F4" />
</LinearGradientBrush>
</Border.Background>
<Border CornerRadius="1" BorderBrush="#FFFFFFFF" BorderThickness="2">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.Resources>
<!-- Start: Previous button template -->
<ControlTemplate x:Key="PreviousButtonTemplate" TargetType="{ x:Type Button}">
<Grid Cursor="Hand">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Storyboard.TargetName="TextColor" Storyboard.TargetProperty="Color" To="#FF73A9D8" Duration="0" />
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Storyboard.TargetName="TextColor" Storyboard.TargetProperty="Opacity" To=".5" Duration="0" />
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Rectangle Fill="#11E5EBF1" Stretch="Fill" Opacity="1"/>
<Grid>
<Path Margin="14,-6,0,0" Height="10" Width="6" VerticalAlignment="Center" HorizontalAlignment="Left" Stretch="Fill" Data="M288.75,232.25 L288.75,240.625 L283,236.625 z">
<Path.Fill>
<SolidColorBrush x:Name="TextColor" Color="#FF333333" />
</Path.Fill>
</Path>
</Grid>
</Grid>
</ControlTemplate>
<ControlTemplate x:Key="NextButtonTemplate" TargetType="{ x:Type Button}">
<Grid Cursor="Hand">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Storyboard.TargetName="TextColor" Storyboard.TargetProperty="Color" To="#FF73A9D8" Duration="0" />
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Storyboard.TargetName="TextColor" Storyboard.TargetProperty="Opacity" To=".5" Duration="0" />
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Rectangle Fill="#11E5EBF1" Stretch="Fill" Opacity="1"/>
<Grid>
<Path Margin="0,-6,14,0" Height="10" Width="6" VerticalAlignment="Center" HorizontalAlignment="Right" Stretch="Fill" Data="M282.875,231.875 L282.875,240.375 L288.625,236 z">
<Path.Fill>
<SolidColorBrush x:Name="TextColor" Color="#FF333333" />
</Path.Fill>
</Path>
</Grid>
</Grid>
</ControlTemplate>
<!-- End: Next button template -->
<!-- Start: Header button template -->
<ControlTemplate x:Key="HeaderButtonTemplate" TargetType="{ x:Type Button}">
<Grid Cursor="Hand">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="MouseOver">
<Storyboard>
<ColorAnimation Storyboard.TargetName="TextColor" Storyboard.TargetProperty="Color" To="Blue" Duration="0" />
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<DoubleAnimation Storyboard.TargetName="buttonContent" Storyboard.TargetProperty="Opacity" To=".5" Duration="0" />
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<!-- This Border is new -->
<Border Padding="12 0"
CornerRadius="6">
<Border.Background>
<LinearGradientBrush StartPoint="0 0" EndPoint="0 1">
<GradientStop Offset="0" Color="#FF73A9D8" />
<GradientStop Offset="1" Color="#FF73A9E8" />
</LinearGradientBrush>
</Border.Background>
<ContentPresenter
x:Name="buttonContent"
Content="{TemplateBinding Content}"
ContentTemplate="{TemplateBinding ContentTemplate}"
Margin="1,4,1,9"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<TextElement.Foreground>
<SolidColorBrush x:Name="TextColor" Color="#FF333333"/>
</TextElement.Foreground>
</ContentPresenter>
</Border>
</Grid>
</ControlTemplate>
<!-- End: Header button template -->
</Grid.Resources>
<!-- Start: Previous button content -->
<Button x:Name="PART_PreviousButton"
Grid.Row="0" Grid.Column="0"
Template="{StaticResource PreviousButtonTemplate}"
Height="20" Width="28"
HorizontalAlignment="Left"
Focusable="False"
/>
<!-- End: Previous button content -->
<!-- Start: Header button content -->
<Button x:Name="PART_HeaderButton"
Grid.Row="0" Grid.Column="1"
Template="{StaticResource HeaderButtonTemplate}"
HorizontalAlignment="Center" VerticalAlignment="Center"
Height="28" Width="110"
FontWeight="Bold" FontSize="10.5"
Focusable="False"
/>
<!-- End: Header button content -->
<!-- Start: Next button content -->
<Button x:Name="PART_NextButton"
Grid.Row="0" Grid.Column="2"
Height="20" Width="28"
HorizontalAlignment="Right"
Template="{StaticResource NextButtonTemplate}"
Focusable="False"
/>
<!-- End: Next button content -->
<!-- Start: Month Content Grid -->
<Grid x:Name="PART_MonthView" Grid.Row="1" Grid.ColumnSpan="3" Visibility="Visible" Margin="6,-1,6,6">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
</Grid>
<!-- End: Month Content Grid -->
<!-- End: Year Content Grid -->
<Grid x:Name="PART_YearView" Grid.Row="1" Grid.ColumnSpan="3" Visibility="Hidden" Margin="6,-3,7,6">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
</Grid>
<!-- End: Year Content Grid -->
</Grid>
</Border>
</Border>
<Rectangle x:Name="PART_DisabledVisual" Opacity="0" Visibility="Collapsed" Stretch="Fill" StrokeThickness="1" RadiusX="2" RadiusY="2" Stroke="{StaticResource DisabledColor}" Fill="{StaticResource DisabledColor}"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="PART_DisabledVisual" Property="Visibility" Value="Visible" />
</Trigger>
<DataTrigger Value="Year">
<DataTrigger.Binding>
<Binding Path="DisplayMode">
<Binding.RelativeSource>
<RelativeSource Mode="FindAncestor" AncestorType="{x:Type Controls:Calendar}" />
</Binding.RelativeSource>
</Binding>
</DataTrigger.Binding>
<Setter TargetName="PART_MonthView" Property="Visibility" Value="Hidden" />
<Setter TargetName="PART_YearView" Property="Visibility" Value="Visible" />
</DataTrigger>
<DataTrigger Value="Decade">
<DataTrigger.Binding>
<Binding Path="DisplayMode">
<Binding.RelativeSource>
<RelativeSource Mode="FindAncestor" AncestorType="{x:Type Controls:Calendar}" />
</Binding.RelativeSource>
</Binding>
</DataTrigger.Binding>
<Setter TargetName="PART_MonthView" Property="Visibility" Value="Hidden" />
<Setter TargetName="PART_YearView" Property="Visibility" Value="Visible" />
</DataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Note: I've got this resource dictionary set at an application level and I'm globally binding the calendarstyle properties to all datepickers.
This is in an app level resource dictionary:
<Style TargetType="{x:Type DatePicker}">
<Setter
Property="CalendarStyle"
Value="{StaticResource CalendarStyle1}" />
</Style>
And this is where the resource dictionaries are referenced (In case I did it wrong, I'm new to xaml
<Application.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary
Source="ResourceDictionary/CustomCalendar.xaml" />
<ResourceDictionary
Source="ResourceDictionary/GlobalStyles.xaml" />
</ResourceDictionary.MergedDictionaries>
</ResourceDictionary>
</Application.Resources>

Your problem is with your style TargetTypes. If you notice you have the style for your calendar defined as:
<Style x:Key="CalendarStyle1" TargetType="{x:Type Calendar}">
And the style for your CalendarItem defined as:
<Style x:Key="CalenderStyleNew" TargetType="primitives:CalendarItem">
The problem is that the Calendar type is from the standard System.Windows.Controls package but the CalendarItem is from the namespace Microsoft.Windows.Controls (that's the wpftoolkit namespace you have defined as primitives). So to fix this you have to either use ALL System.Windows.Controls in your styles or use ALL Microsoft.Windows.Controls namespaces.
I fixed your issue to use all Microsoft.Windows.Controls:
<Style x:Key="CalendarStyle1" TargetType="{x:Type Controls:Calendar}">
The global styles must be changed to:
<Style TargetType="{x:Type Controls:DatePicker}">
<Setter
Property="CalendarStyle"
Value="{StaticResource CalendarStyle1}" />
</Style>
And to instantiate a DatePicker you must use the correct one:
<Controls:DatePicker />
NOT
<DatePicker />
If you don't reference it from the WpfToolkit namespace it won't have your custom styles.
Cheers,
Eric

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