Datepicker inheriting style from Textblock

Question

I have a resource dictionary that contains the following code:

<Style TargetType="{x:Type TextBlock}" >
    <Setter Property="FontSize" Value="20"/>
</Style>

In my app.xaml, I merge it globally:

<Application.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <ResourceDictionary Source="Theme/Default.xaml" />
        </ResourceDictionary.MergedDictionaries>
    </ResourceDictionary>
</Application.Resources>

The problem is that the text "Select a Date" in my DatePickers is influenced by the style of the TextBlock, increasing the total height of the Datepicker (only at runtime; in design it looks ok).

When you start typing a date (or select one using the calendar) it does not inherit from TextBlock style. The problem is only the text "Select a Date".

I don't want to set a Key for every textblock in my app.

What do I do to fix this?

EDIT

Looking closer at the MSDN documentation, we can see that the text of a TextBox control is displayed inside a FrameworkElement, and not a TextBlock.

http://msdn.microsoft.com/en-us/library/ms752068%28v=vs.110%29.aspx

And the DatePicker has it's value displayed as a TextBox. But the text "Select a Date" seems to be a TextBlock over the TextBox.

EDIT 2

I can access the TextBox template inside the DatePicker:

http://msdn.microsoft.com/en-us/library/ff468215%28v=vs.110%29.aspx

But nothing about the textblock...

Answer 1

You are correct by viewing the style of datepicker control you will not able to find your textblock for Select a date. as this is a watermark value on the textbox within the datepicker control. you will require to edit the style of this textbox within this datepicker.

The textbox used within datepicker control is DatepickerTextbox. You will require to modify the style of this textbox. This is quite easy by using expression blend.

<Style x:Key="DatePickerTextBoxStyle1" TargetType="{x:Type DatePickerTextBox}">
            <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.WindowTextBrushKey}}"/>
            <Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.WindowBrushKey}}"/>
            <Setter Property="ScrollViewer.PanningMode" Value="VerticalFirst"/>
            <Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type DatePickerTextBox}">
                        <Grid>
                            <Grid.Resources>
                                <SolidColorBrush x:Key="WatermarkBrush" Color="#FFAAAAAA"/>
                            </Grid.Resources>
                            <VisualStateManager.VisualStateGroups>
                                <VisualStateGroup x:Name="CommonStates">
                                    <VisualStateGroup.Transitions>
                                        <VisualTransition GeneratedDuration="0"/>
                                        <VisualTransition GeneratedDuration="0:0:0.1" To="MouseOver"/>
                                    </VisualStateGroup.Transitions>
                                    <VisualState x:Name="Normal"/>
                                    <VisualState x:Name="MouseOver">
                                        <Storyboard>
                                            <ColorAnimation Duration="0" To="#FF99C1E2" Storyboard.TargetProperty="(Border.BorderBrush).(SolidColorBrush.Color)" Storyboard.TargetName="ContentElement"/>
                                            <ColorAnimation Duration="0" To="#FF99C1E2" Storyboard.TargetProperty="(Border.BorderBrush).(SolidColorBrush.Color)" Storyboard.TargetName="watermark_decorator"/>
                                        </Storyboard>
                                    </VisualState>
                                </VisualStateGroup>
                                <VisualStateGroup x:Name="WatermarkStates">
                                    <VisualStateGroup.Transitions>
                                        <VisualTransition GeneratedDuration="0"/>
                                    </VisualStateGroup.Transitions>
                                    <VisualState x:Name="Unwatermarked"/>
                                    <VisualState x:Name="Watermarked">
                                        <Storyboard>
                                            <DoubleAnimation Duration="0" To="0" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="ContentElement"/>
                                            <DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="PART_Watermark"/>
                                        </Storyboard>
                                    </VisualState>
                                </VisualStateGroup>
                                <VisualStateGroup x:Name="FocusStates">
                                    <VisualStateGroup.Transitions>
                                        <VisualTransition GeneratedDuration="0"/>
                                    </VisualStateGroup.Transitions>
                                    <VisualState x:Name="Unfocused"/>
                                    <VisualState x:Name="Focused">
                                        <Storyboard>
                                            <DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="FocusVisual"/>
                                        </Storyboard>
                                    </VisualState>
                                </VisualStateGroup>
                            </VisualStateManager.VisualStateGroups>
                            <Border x:Name="Border" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" CornerRadius="1" Opacity="1" Padding="{TemplateBinding Padding}">
                                <Grid x:Name="WatermarkContent" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
                                    <Border x:Name="ContentElement" BorderBrush="#FFFFFFFF" BorderThickness="1"/>
                                    <Border x:Name="watermark_decorator" BorderBrush="#FFFFFFFF" BorderThickness="1">
                                        <ContentControl x:Name="PART_Watermark" Focusable="False" IsHitTestVisible="False" Opacity="0" Padding="2"/>
                                    </Border>
                                    <ScrollViewer x:Name="PART_ContentHost" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="0" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"/>
                                    <Border x:Name="FocusVisual" BorderBrush="#FF45D6FA" CornerRadius="1" IsHitTestVisible="False" Opacity="0"/>
                                </Grid>
                            </Border>
                        </Grid>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>

You will need to modify the style PART_Watermark control that is Content control in above style. by modifying this style it will resolve your problem.