Why Are Conditional XAML Setters In Default WinUI Styles Invalid In UWP? - xaml

I copied the default WinUI button style from the WinUI GitHub repo into an empty project. Below is my App.xaml. When I try to run the project, I get this error: The XAML Binary Format (XBF) generator reported syntax error '0x03e9'. If I remove the conditional setters, it runs. The conditional XAML within the control template works fine. What am I doing wrong?
<Application
x:Class="App1.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:contract7Present="http://schemas.microsoft.com/winfx/2006/xaml/presentation?IsApiContractPresent(Windows.Foundation.UniversalApiContract,7)"
xmlns:contract7NotPresent="http://schemas.microsoft.com/winfx/2006/xaml/presentation?IsApiContractNotPresent(Windows.Foundation.UniversalApiContract,7)"
xmlns:local="using:Microsoft.UI.Xaml.Controls"
>
<Application.Resources>
<Style x:Key="DefaultButtonStyle" TargetType="Button">
<Setter Property="Background" Value="{ThemeResource ButtonBackground}" />
<contract7Present:Setter Property="BackgroundSizing" Value="InnerBorderEdge" />
<Setter Property="Foreground" Value="{ThemeResource ButtonForeground}" />
<Setter Property="BorderBrush" Value="{ThemeResource ButtonBorderBrush}" />
<Setter Property="BorderThickness" Value="{ThemeResource ButtonBorderThemeThickness}" />
<contract7NotPresent:Setter Property="Padding" Value="11,5,11,5" />
<contract7Present:Setter Property="Padding" Value="{StaticResource ButtonPadding}" />
<Setter Property="HorizontalAlignment" Value="Left" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}" />
<Setter Property="FontWeight" Value="Normal" />
<Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}" />
<Setter Property="UseSystemFocusVisuals" Value="{StaticResource UseSystemFocusVisuals}" />
<Setter Property="FocusVisualMargin" Value="-3" />
<contract7Present:Setter Property="CornerRadius" Value="{ThemeResource ControlCornerRadius}" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<ContentPresenter
x:Name="ContentPresenter"
Background="{TemplateBinding Background}"
contract7Present:BackgroundSizing="{TemplateBinding BackgroundSizing}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Content="{TemplateBinding Content}"
ContentTemplate="{TemplateBinding ContentTemplate}"
ContentTransitions="{TemplateBinding ContentTransitions}"
contract7Present:CornerRadius="{TemplateBinding CornerRadius}"
contract7NotPresent:CornerRadius="{ThemeResource ControlCornerRadius}"
Padding="{TemplateBinding Padding}"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
AutomationProperties.AccessibilityView="Raw"
local:AnimatedIcon.State="Normal">
<contract7Present:ContentPresenter.BackgroundTransition>
<contract7Present:BrushTransition Duration="0:0:0.083" />
</contract7Present:ContentPresenter.BackgroundTransition>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="PointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
<VisualState.Setters>
<Setter Target="ContentPresenter.(local:AnimatedIcon.State)" Value="PointerOver"/>
</VisualState.Setters>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundPressed}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
<VisualState.Setters>
<Setter Target="ContentPresenter.(local:AnimatedIcon.State)" Value="Pressed"/>
</VisualState.Setters>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
<VisualState.Setters>
<!-- DisabledVisual Should be handled by the control, not the animated icon. -->
<Setter Target="ContentPresenter.(local:AnimatedIcon.State)" Value="Normal"/>
</VisualState.Setters>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
</ContentPresenter>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Application.Resources>


I guess your problem is related to this known issue that basically says that you can't use Setters with Conditional XAML (for the moment?).
You can find a workaround here. First create a base style, then create styles using Conditional XAML. Something like this.
<Application
x:Class="App1.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:contract7NotPresent="http://schemas.microsoft.com/winfx/2006/xaml/presentation?IsApiContractNotPresent(Windows.Foundation.UniversalApiContract,7)"
xmlns:contract7Present="http://schemas.microsoft.com/winfx/2006/xaml/presentation?IsApiContractPresent(Windows.Foundation.UniversalApiContract,7)"
xmlns:local="using:Microsoft.UI.Xaml.Controls">
<Application.Resources>
<Style
x:Key="DefaultButtonBaseStyle"
TargetType="Button">
<Setter Property="Background" Value="{ThemeResource ButtonBackground}" />
<!--<contract7Present:Setter
Property="BackgroundSizing"
Value="InnerBorderEdge" />-->
<Setter Property="Foreground" Value="{ThemeResource ButtonForeground}" />
<Setter Property="BorderBrush" Value="{ThemeResource ButtonBorderBrush}" />
<Setter Property="BorderThickness" Value="{ThemeResource ButtonBorderThemeThickness}" />
<!--<contract7NotPresent:Setter
Property="Padding"
Value="11,5,11,5" />-->
<!--<contract7Present:Setter
Property="Padding"
Value="{StaticResource ButtonPadding}" />-->
<Setter Property="HorizontalAlignment" Value="Left" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}" />
<Setter Property="FontWeight" Value="Normal" />
<Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}" />
<Setter Property="UseSystemFocusVisuals" Value="{StaticResource UseSystemFocusVisuals}" />
<Setter Property="FocusVisualMargin" Value="-3" />
<!--<contract7Present:Setter
Property="CornerRadius"
Value="{ThemeResource ControlCornerRadius}" />-->
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<ContentPresenter
x:Name="ContentPresenter"
Padding="{TemplateBinding Padding}"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
contract7NotPresent:CornerRadius="{ThemeResource ControlCornerRadius}"
contract7Present:BackgroundSizing="{TemplateBinding BackgroundSizing}"
contract7Present:CornerRadius="{TemplateBinding CornerRadius}"
local:AnimatedIcon.State="Normal"
AutomationProperties.AccessibilityView="Raw"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Content="{TemplateBinding Content}"
ContentTemplate="{TemplateBinding ContentTemplate}"
ContentTransitions="{TemplateBinding ContentTransitions}">
<contract7Present:ContentPresenter.BackgroundTransition>
<contract7Present:BrushTransition Duration="0:0:0.083" />
</contract7Present:ContentPresenter.BackgroundTransition>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal" />
<VisualState x:Name="PointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonBackgroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonBorderBrushPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonForegroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
<VisualState.Setters>
<Setter Target="ContentPresenter.(local:AnimatedIcon.State)" Value="PointerOver" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonBackgroundPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonBorderBrushPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonForegroundPressed}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
<VisualState.Setters>
<Setter Target="ContentPresenter.(local:AnimatedIcon.State)" Value="Pressed" />
</VisualState.Setters>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonBorderBrushDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame
KeyTime="0"
Value="{ThemeResource ButtonForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
<VisualState.Setters>
<!-- DisabledVisual Should be handled by the control, not the animated icon. -->
<Setter Target="ContentPresenter.(local:AnimatedIcon.State)" Value="Normal" />
</VisualState.Setters>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
</ContentPresenter>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<contract7Present:Style
x:Key="DefaultButtonStyle"
BasedOn="{StaticResource DefaultButtonBaseStyle}"
TargetType="Button">
<Setter Property="BackgroundSizing" Value="InnerBorderEdge" />
<Setter Property="Padding" Value="{StaticResource ButtonPadding}" />
<!--<Setter Property="CornerRadius" Value="{ThemeResource ControlCornerRadius}" />-->
</contract7Present:Style>
<contract7NotPresent:Style
x:Key="DefaultButtonStyle"
BasedOn="{StaticResource DefaultButtonBaseStyle}"
TargetType="Button">
<Setter Property="Padding" Value="11,5,11,5" />
</contract7NotPresent:Style>
</Application.Resources>
</Application>
BTW, I commented out this line,
<!--<Setter Property="CornerRadius" Value="{ThemeResource ControlCornerRadius}" />-->
since ControlCotnerRadius couldn't be found in my sample app.

Related

How to make background color change when hovering over the mouse? - Xaml

I have the following code:
<Application
x:Class="TiendaVirtual.App"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:TiendaVirtual"
xmlns:viewModel="using:TiendaVirtual.ViewModel"
RequestedTheme="Light">
<Application.Resources>
<viewModel:ArticleViewModel x:Key="ArticleViewModel"></viewModel:ArticleViewModel>
<Style TargetType="Button">
<Setter Property="Background" Value="#26c9ef" />
<Setter Property="Foreground" Value="#fff" />
<Setter Property="FontWeight" Value="Bold" />
<Setter Property="Padding" Value="10,5" />
</Style>
</Application.Resources>
</Application>
What I try to do is a color change when a hover event occurs on my button, I try the following:
<Style TargetType="Button">
<Setter Property="Background" Value="#26c9ef" />
<Setter Property="Foreground" Value="#fff" />
<Setter Property="FontWeight" Value="Bold" />
<Setter Property="Padding" Value="10,5" />
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="Red"/>
</Trigger>
</Style.Triggers>
</Style>
but visual studio tells me that the member "triggers" is not recognized or can not be accessed. I am new with this, what happens and how can I solve it

You can use below style, where you can set the background as you want in PointerOver
<Style x:Name="CustomButtonStyle" TargetType="Button">
<Setter Property="Background" Value="{ThemeResource SystemControlBackgroundBaseLowBrush}" />
<Setter Property="Foreground" Value="{ThemeResource SystemControlForegroundBaseHighBrush}"/>
<Setter Property="BorderBrush" Value="{ThemeResource SystemControlForegroundTransparentBrush}" />
<Setter Property="BorderThickness" Value="{ThemeResource ButtonBorderThemeThickness}" />
<Setter Property="Padding" Value="8,4,8,4" />
<Setter Property="HorizontalAlignment" Value="Left" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}" />
<Setter Property="FontWeight" Value="Normal" />
<Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}" />
<Setter Property="UseSystemFocusVisuals" Value="True" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid x:Name="RootGrid" Background="{TemplateBinding Background}">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal">
<Storyboard>
<PointerUpThemeAnimation Storyboard.TargetName="RootGrid" />
</Storyboard>
</VisualState>
<VisualState x:Name="PointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightBaseMediumLowBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightBaseHighBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="Red" />
</ObjectAnimationUsingKeyFrames>
<PointerUpThemeAnimation Storyboard.TargetName="RootGrid" />
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid"
Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlBackgroundBaseMediumLowBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightBaseHighBrush}" />
</ObjectAnimationUsingKeyFrames>
<PointerDownThemeAnimation Storyboard.TargetName="RootGrid" />
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid"
Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlBackgroundBaseLowBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlDisabledBaseMediumLowBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlDisabledTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<ContentPresenter x:Name="ContentPresenter"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Content="{TemplateBinding Content}"
ContentTransitions="{TemplateBinding ContentTransitions}"
ContentTemplate="{TemplateBinding ContentTemplate}"
Padding="{TemplateBinding Padding}"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
AutomationProperties.AccessibilityView="Raw"/>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

XAML UWP Button with a polygonal shape

How do I make a XAML Button look like the one below (the shape)?
My XAML:
<Button Content="Helpful" Foreground="White" Background="Blue"/>

I use Path instead of Polygon, style like this:
<Page.Resources>
<Style x:Key="ButtonStyle1" TargetType="Button">
<Setter Property="Background" Value="{ThemeResource ButtonBackground}" />
<Setter Property="Foreground" Value="{ThemeResource ButtonForeground}" />
<Setter Property="BorderBrush" Value="{ThemeResource ButtonBorderBrush}" />
<Setter Property="BorderThickness" Value="{ThemeResource ButtonBorderThemeThickness}" />
<Setter Property="Padding" Value="8,4,8,4" />
<Setter Property="HorizontalAlignment" Value="Left" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}" />
<Setter Property="FontWeight" Value="Normal" />
<Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}" />
<Setter Property="UseSystemFocusVisuals" Value="True" />
<Setter Property="FocusVisualMargin" Value="-3" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid x:Name="RootGrid" Background="Transparent">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal">
<Storyboard>
<PointerUpThemeAnimation Storyboard.TargetName="RootGrid" />
</Storyboard>
</VisualState>
<VisualState x:Name="PointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Path" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundPointerOver}" />
</ObjectAnimationUsingKeyFrames>
<PointerUpThemeAnimation Storyboard.TargetName="RootGrid" />
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Path" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushPressed}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundPressed}" />
</ObjectAnimationUsingKeyFrames>
<PointerDownThemeAnimation Storyboard.TargetName="RootGrid" />
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Path" Storyboard.TargetProperty="Fill">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Path
x:Name="Path"
Width="{TemplateBinding Width}"
Height="{TemplateBinding Height}"
HorizontalAlignment="Stretch"
VerticalAlignment="Stretch"
Data="M0,0L17,0 20,-3 23,0 40,0 40,40 0,40z"
Fill="{TemplateBinding Background}"
Stretch="UniformToFill" />
<ContentPresenter
x:Name="ContentPresenter"
Padding="{TemplateBinding Padding}"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
AutomationProperties.AccessibilityView="Raw"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Content="{TemplateBinding Content}"
ContentTemplate="{TemplateBinding ContentTemplate}"
ContentTransitions="{TemplateBinding ContentTransitions}" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Page.Resources>
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<Button
Width="120"
Height="48"
Background="Blue"
BorderThickness="0"
Content="OK"
Foreground="White"
Style="{StaticResource ButtonStyle1}" />
</Grid>

Make border show for selected button of multiple row of buttons

I used following style for showing bottom border for button on mouse hover and click.. its working fine, but after clicking the border is not showing
<Style x:Key="ButtonStyleOrders1" TargetType="Button">
<Setter Property="Background" Value="{ThemeResource ButtonBackground}"/>
<Setter Property="Foreground" Value="{ThemeResource ButtonForeground}"/>
<Setter Property="BorderBrush" Value="{ThemeResource ButtonBorderBrush}"/>
<Setter Property="BorderThickness" Value="{ThemeResource ButtonBorderThemeThickness}"/>
<Setter Property="Padding" Value="8,4,8,4"/>
<Setter Property="HorizontalAlignment" Value="Left"/>
<Setter Property="VerticalAlignment" Value="Center"/>
<Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}"/>
<Setter Property="FontWeight" Value="Normal"/>
<Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}"/>
<Setter Property="UseSystemFocusVisuals" Value="True"/>
<Setter Property="FocusVisualMargin" Value="-3"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Grid x:Name="RootGrid" Background="{TemplateBinding Background}">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal">
<VisualState.Setters>
<Setter Target="ContentPresenter.(ContentPresenter.Background)">
<Setter.Value>
<SolidColorBrush Color="White"/>
</Setter.Value>
</Setter>
<Setter Target="ContentPresenter.(ContentPresenter.BorderBrush)">
<Setter.Value>
<SolidColorBrush Color="#FF2C8CA1"/>
</Setter.Value>
</Setter>
<Setter Target="ContentPresenter.(ContentPresenter.BorderThickness)">
<Setter.Value>
<Thickness>0</Thickness>
</Setter.Value>
</Setter>
</VisualState.Setters>
<Storyboard>
<PointerUpThemeAnimation Storyboard.TargetName="RootGrid"/>
</Storyboard>
</VisualState>
<VisualState x:Name="PointerOver">
<VisualState.Setters>
<Setter Target="ContentPresenter.(ContentPresenter.Background)">
<Setter.Value>
<SolidColorBrush Color="White"/>
</Setter.Value>
</Setter>
</VisualState.Setters>
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="RootGrid">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundPointerOver}"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="BorderBrush" Storyboard.TargetName="ContentPresenter">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<SolidColorBrush Color="#FF2C8CA1"/>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Foreground" Storyboard.TargetName="ContentPresenter">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundPointerOver}"/>
</ObjectAnimationUsingKeyFrames>
<PointerUpThemeAnimation Storyboard.TargetName="RootGrid"/>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed">
<VisualState.Setters>
<Setter Target="ContentPresenter.(ContentPresenter.Background)">
<Setter.Value>
<SolidColorBrush Color="White"/>
</Setter.Value>
</Setter>
</VisualState.Setters>
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="RootGrid">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundPressed}"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="BorderBrush" Storyboard.TargetName="ContentPresenter">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<SolidColorBrush Color="#FF2C8CA1"/>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Foreground" Storyboard.TargetName="ContentPresenter">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForegroundPressed}"/>
</ObjectAnimationUsingKeyFrames>
<PointerDownThemeAnimation Storyboard.TargetName="RootGrid"/>
</Storyboard>
</VisualState>
<VisualState x:Name="Disabled">
<VisualState.Setters>
<Setter Target="ContentPresenter.(ContentPresenter.Background)">
<Setter.Value>
<SolidColorBrush Color="White"/>
</Setter.Value>
</Setter>
<Setter Target="ContentPresenter.(ContentPresenter.BorderThickness)">
<Setter.Value>
<Thickness>0</Thickness>
</Setter.Value>
</Setter>
</VisualState.Setters>
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="RootGrid">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackgroundDisabled}"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="BorderBrush" Storyboard.TargetName="ContentPresenter">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrushDisabled}"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Foreground" Storyboard.TargetName="ContentPresenter">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<SolidColorBrush Color="Black"/>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="VisualStateGroup"/>
</VisualStateManager.VisualStateGroups>
<ContentPresenter x:Name="ContentPresenter" AutomationProperties.AccessibilityView="Raw" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" ContentTemplate="{TemplateBinding ContentTemplate}" ContentTransitions="{TemplateBinding ContentTransitions}" Content="{TemplateBinding Content}" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" Padding="{TemplateBinding Padding}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}" Background="White"/>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
i want to make button with bottom border after clicked and until selecting next button please provide the solution

According to your description, using the RadioButton should meet your requirement.
You could custom its style and make it looks like a button, then you could add other effect in its visual state.
I've made a simple style for you reference:
<Page ...>
<Page.Resources>
<Style x:Key="RadioButtonStyle1" TargetType="RadioButton">
<Setter Property="Background" Value="{ThemeResource RadioButtonBackground}" />
<Setter Property="Foreground" Value="{ThemeResource RadioButtonForeground}" />
<Setter Property="BorderBrush" Value="{ThemeResource RadioButtonBorderBrush}" />
<Setter Property="Padding" Value="8,6,0,0" />
<Setter Property="HorizontalAlignment" Value="Left" />
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="HorizontalContentAlignment" Value="Left" />
<Setter Property="VerticalContentAlignment" Value="Top" />
<Setter Property="FontFamily" Value="{ThemeResource ContentControlThemeFontFamily}" />
<Setter Property="FontSize" Value="{ThemeResource ControlContentThemeFontSize}" />
<Setter Property="MinWidth" Value="120" />
<Setter Property="UseSystemFocusVisuals" Value="True" />
<Setter Property="FocusVisualMargin" Value="-7,-3,-7,-3" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="RadioButton">
<Grid x:Name="RootGrid" Background="{TemplateBinding Background}" BorderThickness="3">
<ContentPresenter x:Name="ContentPresenter" Margin="{TemplateBinding Padding}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}" AutomationProperties.AccessibilityView="Raw" Content="{TemplateBinding Content}" ContentTemplate="{TemplateBinding ContentTemplate}" ContentTransitions="{TemplateBinding ContentTransitions}" Foreground="{TemplateBinding Foreground}" />
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForeground}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackground}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="PointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForeground}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="Red" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="BorderThickness">
<DiscreteObjectKeyFrame KeyTime="0" Value="2" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackground}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Pressed" />
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource RadioButtonForegroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource RadioButtonBackgroundDisabled}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource RadioButtonBorderBrushDisabled}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="CheckStates">
<VisualState x:Name="Checked">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="Red" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="BorderThickness">
<DiscreteObjectKeyFrame KeyTime="0" Value="2" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Unchecked">
<Storyboard>
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonForeground}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBackground}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="RootGrid" Storyboard.TargetProperty="BorderBrush">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource ButtonBorderBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</Storyboard>
</VisualState>
<VisualState x:Name="Indeterminate" />
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Page.Resources>
<Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
<StackPanel>
<RadioButton Content="option1" GroupName="r" Style="{StaticResource RadioButtonStyle1}" />
<RadioButton Content="option2" GroupName="r" Style="{StaticResource RadioButtonStyle1}" />
<RadioButton Content="option3" GroupName="r" Style="{StaticResource RadioButtonStyle1}" />
</StackPanel>
</Grid>
</Page>

Align Pivot Header items in Center of the Page

I am using Pivot control in my UWP application. The problem is that Pivot aligns its Header items on the left side of the page. Is it possible to align them in the center of the page? I have tried this with custom style for PivotItemHeader, but it didn't work out. My style is shown below.
<Style TargetType="PivotHeaderItem">
<Setter Property="FontSize" Value="{ThemeResource PivotHeaderItemFontSize}" />
<Setter Property="FontFamily" Value="{ThemeResource PivotHeaderItemFontFamily}" />
<Setter Property="FontWeight" Value="{ThemeResource PivotHeaderItemThemeFontWeight}" />
<Setter Property="CharacterSpacing" Value="{ThemeResource PivotHeaderItemCharacterSpacing}" />
<Setter Property="Background" Value="Transparent" />
<Setter Property="Foreground" Value="Gray" />
<!-- original value {ThemeResource SystemControlForegroundBaseMediumBrush} -->
<Setter Property="Padding" Value="{ThemeResource PivotHeaderItemMargin}" />
<Setter Property="Height" Value="48" />
<Setter Property="VerticalContentAlignment" Value="Center" />
<Setter Property="IsTabStop" Value="False" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="PivotHeaderItem">
<Grid x:Name="Grid" Background="{TemplateBinding Background}">
<Grid.Resources>
<Style x:Key="BaseContentPresenterStyle" TargetType="ContentPresenter">
<Setter Property="FontFamily" Value="Segoe UI" />
<Setter Property="FontWeight" Value="SemiBold" />
<Setter Property="FontSize" Value="15" />
<Setter Property="TextWrapping" Value="Wrap" />
<Setter Property="LineStackingStrategy" Value="MaxHeight" />
<Setter Property="TextLineBounds" Value="Full" />
<Setter Property="OpticalMarginAlignment" Value="TrimSideBearings" />
</Style>
<Style x:Key="BodyContentPresenterStyle" TargetType="ContentPresenter" BasedOn="{StaticResource BaseContentPresenterStyle}">
<Setter Property="FontFamily" Value="{ThemeResource PivotHeaderItemFontFamily}" />
<Setter Property="FontWeight" Value="{ThemeResource PivotHeaderItemThemeFontWeight}" />
<Setter Property="FontSize" Value="{ThemeResource PivotHeaderItemFontSize}" />
</Style>
</Grid.Resources>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="SelectionStates">
<VisualStateGroup.Transitions>
<VisualTransition From="Unselected" To="UnselectedLocked" GeneratedDuration="0:0:0.33" />
<VisualTransition From="UnselectedLocked" To="Unselected" GeneratedDuration="0:0:0.33" />
</VisualStateGroup.Transitions>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlDisabledBaseMediumLowBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Unselected" />
<VisualState x:Name="UnselectedLocked">
<Storyboard>
<DoubleAnimation Storyboard.TargetName="ContentPresenterTranslateTransform" Storyboard.TargetProperty="X" Duration="0" To="{ThemeResource PivotHeaderItemLockedTranslation}" />
<DoubleAnimation Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="(UIElement.Opacity)" Duration="0" To="0" />
</Storyboard>
</VisualState>
<VisualState x:Name="Selected">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource currentThemeColor}" />
<!-- original value {ThemeResource SystemControlHighlightAltBaseHighBrush} -->
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="UnselectedPointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightAltBaseMediumHighBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="SelectedPointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightAltBaseMediumHighBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="UnselectedPressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightAltBaseMediumHighBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="SelectedPressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter" Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightAltBaseMediumHighBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<ContentPresenter x:Name="ContentPresenter" Content="{TemplateBinding Content}" ContentTemplate="{TemplateBinding ContentTemplate}" Margin="{TemplateBinding Padding}" FontSize="{TemplateBinding FontSize}" FontFamily="{TemplateBinding FontFamily}" FontWeight="{TemplateBinding FontWeight}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<ContentPresenter.RenderTransform>
<TranslateTransform x:Name="ContentPresenterTranslateTransform" />
</ContentPresenter.RenderTransform>
</ContentPresenter>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

If I understood you correctly, you want to center all the headers. If so, then you don't want to change PivotHeaderItem, but Pivot's style. There you will find something like HeaderClipper, change its default HorizontalContentAlignment from Stretch to Center and it should work:
<!-- some code before -->
<ContentControl x:Name="HeaderClipper" Grid.Column="1" HorizontalContentAlignment="Center" UseSystemFocusVisuals="True">
<!-- some code before -->

Apply PivotItemHeader style to PivotItem in UWP

I have created a PivotItemHeader style with a key in resources but don't know where to apply this although if I remove Key it will be applied to all the PivotItemHeader but I don't want to do that, I want to apply this only for selected Pivot.
<Style TargetType="PivotHeaderItem" x:Key"PivotHeaderItemInnserStyle">
<Setter Property="FontSize" Value="{ThemeResource PivotHeaderItemFontSize}" />
<Setter Property="FontFamily" Value="{ThemeResource PivotHeaderItemFontFamily}" />
<Setter Property="FontWeight" Value="{ThemeResource PivotHeaderItemThemeFontWeight}" />
<Setter Property="CharacterSpacing" Value="{ThemeResource PivotHeaderItemCharacterSpacing}" />
<Setter Property="Background" Value="{StaticResource PivotHeaderItemSelectedBackgroundBrush}" />
<Setter Property="Foreground" Value="#FFEAE8E8" />
<Setter Property="Padding" Value="0" />
<Setter Property="Margin" Value="0" />
<Setter Property="Height" Value="48" />
<Setter Property="VerticalContentAlignment" Value="Stretch" />
<Setter Property="IsTabStop" Value="False" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="PivotHeaderItem">
<Grid
x:Name="Grid"
Background="{TemplateBinding Background}">
<Grid.Resources>
<Style x:Key="BaseContentPresenterStyle" TargetType="ContentPresenter">
<Setter Property="FontFamily" Value="XamlAutoFontFamily"/>
<Setter Property="FontWeight" Value="SemiBold"/>
<Setter Property="FontSize" Value="15"/>
<Setter Property="TextWrapping" Value="Wrap"/>
<Setter Property="LineStackingStrategy" Value="MaxHeight"/>
<Setter Property="TextLineBounds" Value="Full"/>
<Setter Property="OpticalMarginAlignment" Value="TrimSideBearings"/>
</Style>
<Style x:Key="BodyContentPresenterStyle" TargetType="ContentPresenter" BasedOn="{StaticResource BaseContentPresenterStyle}">
<Setter Property="FontFamily" Value="{ThemeResource PivotHeaderItemFontFamily}" />
<Setter Property="FontWeight" Value="{ThemeResource PivotHeaderItemThemeFontWeight}"/>
<Setter Property="FontSize" Value="{ThemeResource PivotHeaderItemFontSize}"/>
</Style>
</Grid.Resources>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="SelectionStates">
<VisualStateGroup.Transitions>
<VisualTransition From="Unselected" To="UnselectedLocked" GeneratedDuration="0:0:0.33" />
<VisualTransition From="UnselectedLocked" To="Unselected" GeneratedDuration="0:0:0.33" />
</VisualStateGroup.Transitions>
<VisualState x:Name="Disabled">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlDisabledBaseMediumLowBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Unselected" />
<VisualState x:Name="UnselectedLocked">
<Storyboard>
<DoubleAnimation Storyboard.TargetName="ContentPresenterTranslateTransform"
Storyboard.TargetProperty="X"
Duration="0" To="{ThemeResource PivotHeaderItemLockedTranslation}" />
<DoubleAnimation Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="(UIElement.Opacity)"
Duration="0" To="0" />
</Storyboard>
</VisualState>
<VisualState x:Name="Selected">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemHoverForegroundBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="UnselectedPointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemHoverForegroundBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid"
Storyboard.TargetProperty="Background" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="headerItemBorder"
Storyboard.TargetProperty="Background" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemHoverBackgroundBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="SelectedPointerOver">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemHoverForegroundBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid"
Storyboard.TargetProperty="Background" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{ThemeResource SystemControlHighlightTransparentBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="headerItemBorder"
Storyboard.TargetProperty="Background" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemHoverBackgroundBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="UnselectedPressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemUnSelectedPressedForegroundBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid"
Storyboard.TargetProperty="Background" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemUnSelectedPressedBackgroundBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="SelectedPressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemSelectedPressedForegroundBrush}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="Grid"
Storyboard.TargetProperty="Background" >
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PivotHeaderItemSelectedPressedBackgroundBrush}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<!--Content="{TemplateBinding Content}"-->
<ContentPresenter
x:Name="ContentPresenter"
Foreground="Gray"
ContentTemplate="{TemplateBinding ContentTemplate}"
Margin="{TemplateBinding Padding}"
FontSize="{TemplateBinding FontSize}"
FontFamily="{TemplateBinding FontFamily}"
FontWeight="{TemplateBinding FontWeight}"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
<ContentPresenter.RenderTransform>
<TranslateTransform x:Name="ContentPresenterTranslateTransform" />
</ContentPresenter.RenderTransform>
<Border Name="headerItemBorder" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Padding="16,2">
<TextBlock Text="{TemplateBinding Content}" FontFamily="{StaticResource PivotHeaderItemFontFamily}" FontSize="{StaticResource PivotHeaderItemFontSize}"
/>
</Border>
</ContentPresenter>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

Well I got one possible solution to achieve this,
The inner Pivot will have resources and there we'll define the style again for PivotHeaderItem which is based on the style of our defined style for inner pivot.
<Pivot>
<PivotItem Header="SCAN" />
<PivotItem Header="DEMOGRAPHICS" />
<PivotItem Header="FINGERPRINTS">
<Pivot>
<Pivot.Resources>
<Style TargetType="PivotHeaderItem" BasedOn="{StaticResource PivotHeaderItemInnerPivotStyle}" />
</Pivot.Resources>
<PivotItem Header="Sub Pi 1" />
<PivotItem Header="Sub Pi 2" />
<PivotItem Header="Sub Pi 3" />
</Pivot>
</PivotItem>
<PivotItem Header="PALMPRINTS"/>
PivotHeaderItemInnerPivotStyle is the style we have created for inner pivot header item.