我有一个带有 PCL、Android、iOS 和 UWP 项目的跨平台 Xamarin Forms 应用程序。在 UWP 项目中,我正在尝试将选项卡式页面的样式设置为所选选项卡带有下划线的位置,就像在 Android 项目中一样,并且无论手机大小如何,选项卡都会占用屏幕上的空间。在 UWP App.xaml 中,我能够修改“PivotHeaderItem”样式以更改选项卡的颜色和宽度,但宽度当前是硬编码的,因此选项卡仅在 5" 模拟器和标签没有下划线。下面是我的代码和截图。提前谢谢!
<!--11/28/17 | Style below removes extra unneeded padding on TabbedPage Children Pages-->
<Style TargetType="PivotItem">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Margin" Value="{ThemeResource PivotItemMargin}"/>
<Setter Property="Margin" Value="0,0,0,0"/>
<Setter Property="Padding" Value="0"/>
<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
<Setter Property="VerticalContentAlignment" Value="Stretch"/>
<Setter Property="IsTabStop" Value="False"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="PivotItem">
<Grid Background="{TemplateBinding Background}"
HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
VerticalAlignment="{TemplateBinding
VerticalAlignment}">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="Pivot">
<VisualState x:Name="Right"/>
<VisualState x:Name="Left"/>
<VisualState x:Name="Center"/>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<ContentPresenter HorizontalAlignment="{TemplateBinding
HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding
VerticalContentAlignment}"
ContentTemplate="{TemplateBinding
ContentTemplate}"
Content="{TemplateBinding Content}" Margin="
{TemplateBinding Padding}"/>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<!--11/28/17 | Style below changes the Background/Foreground of TabbedPage
Tabs-->
<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="White"/>
<Setter Property="Foreground" Value="Black"/>
<!--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="#2196F3" Width="180">
<!-- original value {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="#2196F3"/> <!--| {ThemeResource
SystemControlDisabledBaseMediumLowBrush} |-->
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Unselected">
<Storyboard>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0"
Value="White"/> <!--original value {ThemeResource
SystemControlHighlightAltBaseHighBrush}-->
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0"
Value="#2196F3"/> <!--| #1769aa #C7CECA |-->
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<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="White"/> <!--original value {ThemeResource
SystemControlHighlightAltBaseHighBrush}-->
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0"
Value="#2196F3"/> <!--| #C7CECA |-->
</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="White"/> <!--| {ThemeResource
SystemControlHighlightAltBaseMediumHighBrush} |-->
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0"
Value="#2196F3"/> <!--|#1769aa {ThemeResource
SystemControlHighlightTransparentBrush} |-->
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="SelectedPressed">
<Storyboard>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="ContentPresenter"
Storyboard.TargetProperty="Foreground">
<DiscreteObjectKeyFrame KeyTime="0"
Value="White"/> <!--| {ThemeResource
SystemControlHighlightAltBaseMediumHighBrush} |-->
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames
Storyboard.TargetName="Grid" Storyboard.TargetProperty="Background">
<DiscreteObjectKeyFrame KeyTime="0"
Value="#2196F3"/> <!--| {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>